Article reflection in urben design Essay Example | Topics and Well Written Essays - 1000 words

Article reflection in urben design - Essay Example I like using my smart phone during travel times. I see my travel time as a good way to do those things which I would otherwise be unable to while in the house or in otherwise busy environments such as the classroom or at work. I can say for sure that Smart phones have really changed my travelling experience. Not only can I search for different things as I travel around, but am also able to catch up with news from online sources. Armed with a smart phone, my commuting episodes are always an interesting and productive. The time I use in a public transport medium is never wasted because I use it to do other things such as researching for my course. The things I can do while using a public means of transport range from playing my favourite Smartphone games, to catching up with news from digital versions of the major newspapers. Watching videos online is also an important part of the things which I do during the travel time. On my travels, I also realise that am not the only one who is be nefiting from the portable technologies. Although I personally only use my Smartphone and rarely carries other portable devices such as tablet computers, I realise that most people these days are carrying portable devices on their travels. These digital devices include laptops and tablet computers and these people are never shy to use these devices (Schwieterman 30-35). These people are usually busy on their digital devices, usually with earphones tagged to their ears which mean that they are listening to something. When travelling, I usually like listening to my favourite FM especially during the breakfast shows or the drive-on shows in the evening. I listen to my favourite FM but during the times when there is nothing interesting to listen to, I can listen to my favourite music on the phone. I also like listening to podcasts which I also download online. There is one trend which I have realised with me. For instance, I have noticed that I rarely do the things which I do with my ph one when I am in the house. When am in the house, I rarely ever listen to radio or podcasts. I only find these things interesting when am travelling as a way to keep myself busy. However, listening to music and podcasts are not the only things I do with my phone. I do extensive useful work such as researching for my course. With easy use of internet on my iPhone, I find it easy to be able to use the internet for research. I am very fond of reading articles online on my phone while listening to music on the background. This helps me to pass time and to be able to travel in ease. I also play games as I have installed a number of apps for gaming on my phone. The list of the things I can do on my phone are endless. Most of these activities I only engage when using public transport, not only to pass time, but also to relax myself. I have found public transport very relaxing because I can engage in whatever things I want to do unlike when I am driving. Driving, while at some times enjoyab le, has its own share of troubles. For example a flat tyre always seems to come at the most incontinent of times. The occasional speeding ticket and other minor incontinences also make driving a wreck in most cases. On the other hand, travelling through public transport means that I can sit back and relax and wait for my destination to come to me. Using

Fast Food and the Problems with Fast Food Essay Example for Free

Fast Food and the Problems with Fast Food Essay Fast Food Having an Effect on U. S Health Fast food chains are anywhere and everywhere. You cannot drive to town without passing at least two or three of these â€Å"restaurants. † The concept behind fast food was a good idea, but the results were catastrophic in the health aspect. Now that fast food has become one of the top industries in the world, everything has gone awry. The fast food industry has drastically changed the way people view food, how convenience is rising and the cost for products. Fast food restaurants first started as drive-ins with car hops, but in the 1980’s began with drive-thru windows. McDonald’s was one of the first ones to convert from car hops to drive-thru windows. The idea of fast food service brought about a whole new concept to how we view food. Without proper education in the health field typical Americans would not know what their body needs and what they consume. Maybe if that was the case the obesity rate and rates of chronic heart disease would plummet and we could focus on more important problems. When these restaurants began to spring up, it spread like wildfire. Sonic, McDonalds, Burger King, Wendy’s and etc. all became multi-million dollar companies. They discovered they could mass-produce products that were cheap and that could make them money faster than what they had to been doing before (Super-Size Me). Fast food has sprung up and become a leading industry because they are focused on quick, cheap food for people. Despite how bad it is for them it is cheap and fast to produce. They are extremely convenient due to the drive-thru windows that are being incorporated into any and all fast food restaurants. The food that you buy is relatively inexpensive and cheap also. Another key point to fast food restaurants popularity is that they are advertising their foods more towards the children. McDonald’s has their cartoon show that advertises their products to children along with the play places and their mascot, Ronald McDonald. They also incorporate toys and such for the kids’ meals. Burger King does something similar to McDonald’s with their characters. There are many lawsuits against corporations advertising to children for fast food, which are still being reviewed for the time being. This advertising is being sued because of the high rates of obesity in younger children is sky rocketing and chronic heart diseases at younger ages is also a factor in these lawsuits (Food, Inc). The health factors play perhaps the largest role in any type of food industry. â€Å"The disadvantages to fast food is that the products are higher in soya, fat, sugar, oil, fried meat, salt cheese, mayonnaise, and obviously salt†(Bose). There are very little nutrients in fast food if any due to the process of frying the foods to cook them. There is also bacteria present on the food before frying it which can do harm to our bodies if not destroyed also. There is a direct link between fast food and obesity, coronary heart disease (CHD) and diabetes. Fast food is loaded with salt and fats that are not needed for the body to function which after a long period of â€Å"exposure† can lead to CHD and obesity. â€Å"Eating fast food two or more times a week was also found to increase the risk of developing type 2 diabetes by 27 percent† (University of Minnesota). The advantages of fast food are more for convenience than nutrition. †In a survey done by WebMD the top 11 reasons for eating fast food are as follows: They’re quick, they’re easy to get to, I like the taste of fast food, they’re inexpensive, I’m too busy to cook, it’s a â€Å"treat† for myself, I don’t like to prepare foods myself, I don’t like to prepare foods myself, My friends/family like them, it is a way of socializing with friends and family, they have many nutritious foods to offer, they’re fun and entertaining†(Hitti). This survey just shows that most Americans do not have time or do not make the time to prepare meals for themselves and their families. If families are too be healthier individuals they need to make time to prepare meals for the entire family. Choosing one day out of the week to cook meals for the whole week is a great and convenient solution to this problem. The major chains that have flourished greatly are McDonald’s with their advertising towards children and very inexpensive foods, Burger King with their better â€Å"quality† tasting food, and Sonic which kept the drive in style fast food, but incorporated a drive thru into their layout. Each of these restaurants have one thing in common, they all advertise to children as their main concentration. Keeping their restaurants friendly and geared towards kids pushes the kids to want to keep going to these places so they can eat and play. Sonic does not offer a play place or anything like what Burger King and McDonald’s have. Sonic keeps more of the older style of fast food using car hops and drive ins which plays to their advantage being one of the very few restaurants that even do this anymore. One of the biggest problems with fast food is that they try to keep us in the dark about what we are consuming. That should raise the question of what is being hidden from us. In the documentary, Food Inc. all of the corporations producing foods refused to comment on their procedures. The farmers were not even allowed to let the cameramen into their chicken houses. This alone should tell us there is something that these companies are hiding that could cause them to lose a lot of money. If you watch closely to how these companies operate then that alone should raise an eyebrow or two as to what is their big secret and why are we the consumers kept in the dark about this. For McDonalds, the chicken nuggets they sale are not actually chicken nuggets. The â€Å"nuggets† are the leftovers of the chicken made into a pink paste like substance that is then made into a chicken nugget. None of the meats made are 100 percent beef or chicken or fish. The products are leftovers of the real ingredients ground up and mixed with other products to make what we consume. Trans-fatty acids are placed into the products to preserve them which only make them worse for us, which leads to insulin resistance over time and cause Type 2 diabetes. The beef has been reported to have less than 2 percent actual beef in the burgers. Many of the mystery ingredients in fast food are typically industrial chemicals. The occurrence with deaths due to how our food is processed is becoming a major concern for most states. Unfortunately FDA regulations are very lax with food processing companies and fast food companies because some of the â€Å"big wigs† are working for these food companies (Food, Inc. ). The beef that is being processed for our consumption are typically standing in their own manure, which causes infected meats and disease ridden food. Also chicken houses are very similar to the way beef is raised. The chickens are packed into these houses and pumped with steroids so they will grow much faster and much larger than normal. This means less time spent raising the chicken and faster money in the pockets of the corporations. Food is an essential part of life. It is necessary to live and to function throughout the day. The type of food we consume is up to us, we can have healthy, nutritious food or we can have quick, unhealthy food. The choice comes down to our knowledge of what we consume and need as humans. Unfortunately fast food has changed how we view food, how convenience is a greater commodity than nutrition and the cost for products. Works Cited Bose, Debopriya. â€Å"Advantages and Disadvantages of Fast Food. † 12 Nov. 2013. Buzzle. Web. Clarke, Nancy. â€Å"Health Risks Involved When Eating Fast Food. † 9 Sep. 2013. Demand Media. Web. Food, Inc. Dir. Robert Kenner. Perf. Michael Pollan, Eric Schlosser, Gary Hirschberg, and Joe Halatin. Magnolia Pictures, 2008. Documentary. Henshaw, Ashley. â€Å"The Major Health Hazards of Fast Food. † 9 Sept. 2013. SymptomFind. Web. Hitti, Miranda. â€Å"Top 11 Reasons for Fast Food’s Popularity. † 12 Nov. 2013. WebMD. Web. Pereira, Mark, David S. Ludwig, Alex I. Kartashov, Cara B. Ebbeling, Linda Van Horn, Martha L. Slattery, David R. Jacobs. â€Å"Fast-food Habits, Weight Gain, and Insulin Resistance (The CARDIA Study): 15-Year Prospective Analysis. † 9 Sept. 2013. 365. 9453(2005): 36-42. Web. 9 Sept. 2013 Martindale, Diane. â€Å"Fast Food is a Major Public Health Hazard 177. 2380. † 2 July 2012. Organic Consumers Association. 9 Sept. 2013. Web. Super-Size Me. Dir. Morgan Spurlock. Perf. Morgan Spurlock, Daryl Isaacs, and Lisa Ganjhu. Kathbur Pictures, 2004. Documentary. University of Minnesota Academic Health Center. â€Å"Fast Food Intake Increases Risk of Diabetes and Heart Disease in Singapore. † ScienceDaily. 9 Sept. 2013. Web. Weiss, Thomas C. â€Å"Associated Health Risks of Eating Fast Foods. †. Disabled World. Fast Food Having an Effect on U. S Health Fast food chains are anywhere and everywhere. You cannot drive to town without passing at least two or three of these â€Å"restaurants. † The concept behind fast food was a good idea, but the results were catastrophic in the health aspect. Now that fast food has become one of the top industries in the world, everything has gone awry. The fast food industry has drastically changed the way people view food, how convenience is rising and the cost for products. Fast food restaurants first started as drive-ins with car hops, but in the 1980’s began with drive-thru windows. McDonald’s was one of the first ones to convert from car hops to drive-thru windows. The idea of fast food service brought about a whole new concept to how we view food. Without proper education in the health field typical Americans would not know what their body needs and what they consume. Maybe if that was the case the obesity rate and rates of chronic heart disease would plummet and we could focus on more important problems. When these restaurants began to spring up, it spread like wildfire. Sonic, McDonalds, Burger King, Wendy’s and etc. all became multi-million dollar companies. They discovered they could mass-produce products that were cheap and that could make them money faster than what they had to been doing before (Super-Size Me). Fast food has sprung up and become a leading industry because they are focused on quick, cheap food for people. Despite how bad it is for them it is cheap and fast to produce. They are extremely convenient due to the drive-thru windows that are being incorporated into any and all fast food restaurants. The food that you buy is relatively inexpensive and cheap also. Another key point to fast food restaurants popularity is that they are advertising their foods more towards the children. McDonald’s has their cartoon show that advertises their products to children along with the play places and their mascot, Ronald McDonald. They also incorporate toys and such for the kids’ meals. Burger King does something similar to McDonald’s with their characters. There are many lawsuits against corporations advertising to children for fast food, which are still being reviewed for the time being. This advertising is being sued because of the high rates of obesity in younger children is sky rocketing and chronic heart diseases at younger ages is also a factor in these lawsuits (Food, Inc). The health factors play perhaps the largest role in any type of food industry. â€Å"The disadvantages to fast food is that the products are higher in soya, fat, sugar, oil, fried meat, salt cheese, mayonnaise, and obviously salt†(Bose). There are very little nutrients in fast food if any due to the process of frying the foods to cook them. There is also bacteria present on the food before frying it which can do harm to our bodies if not destroyed also. There is a direct link between fast food and obesity, coronary heart disease (CHD) and diabetes. Fast food is loaded with salt and fats that are not needed for the body to function which after a long period of â€Å"exposure† can lead to CHD and obesity. â€Å"Eating fast food two or more times a week was also found to increase the risk of developing type 2 diabetes by 27 percent† (University of Minnesota). The advantages of fast food are more for convenience than nutrition. †In a survey done by WebMD the top 11 reasons for eating fast food are as follows: They’re quick, they’re easy to get to, I like the taste of fast food, they’re inexpensive, I’m too busy to cook, it’s a â€Å"treat† for myself, I don’t like to prepare foods myself, I don’t like to prepare foods myself, My friends/family like them, it is a way of socializing with friends and family, they have many nutritious foods to offer, they’re fun and entertaining†(Hitti). This survey just shows that most Americans do not have time or do not make the time to prepare meals for themselves and their families. If families are too be healthier individuals they need to make time to prepare meals for the entire family. Choosing one day out of the week to cook meals for the whole week is a great and convenient solution to this problem. The major chains that have flourished greatly are McDonald’s with their advertising towards children and very inexpensive foods, Burger King with their better â€Å"quality† tasting food, and Sonic which kept the drive in style fast food, but incorporated a drive thru into their layout. Each of these restaurants have one thing in common, they all advertise to children as their main concentration. Keeping their restaurants friendly and geared towards kids pushes the kids to want to keep going to these places so they can eat and play. Sonic does not offer a play place or anything like what Burger King and McDonald’s have. Sonic keeps more of the older style of fast food using car hops and drive ins which plays to their advantage being one of the very few restaurants that even do this anymore. One of the biggest problems with fast food is that they try to keep us in the dark about what we are consuming. That should raise the question of what is being hidden from us. In the documentary, Food Inc. all of the corporations producing foods refused to comment on their procedures. The farmers were not even allowed to let the cameramen into their chicken houses. This alone should tell us there is something that these companies are hiding that could cause them to lose a lot of money. If you watch closely to how these companies operate then that alone should raise an eyebrow or two as to what is their big secret and why are we the consumers kept in the dark about this. For McDonalds, the chicken nuggets they sale are not actually chicken nuggets. The â€Å"nuggets† are the leftovers of the chicken made into a pink paste like substance that is then made into a chicken nugget. None of the meats made are 100 percent beef or chicken or fish. The products are leftovers of the real ingredients ground up and mixed with other products to make what we consume. Trans-fatty acids are placed into the products to preserve them which only make them worse for us, which leads to insulin resistance over time and cause Type 2 diabetes. The beef has been reported to have less than 2 percent actual beef in the burgers. Many of the mystery ingredients in fast food are typically industrial chemicals. The occurrence with deaths due to how our food is processed is becoming a major concern for most states. Unfortunately FDA regulations are very lax with food processing companies and fast food companies because some of the â€Å"big wigs† are working for these food companies (Food, Inc. ). The beef that is being processed for our consumption are typically standing in their own manure, which causes infected meats and disease ridden food. Also chicken houses are very similar to the way beef is raised. The chickens are packed into these houses and pumped with steroids so they will grow much faster and much larger than normal. This means less time spent raising the chicken and faster money in the pockets of the corporations. Food is an essential part of life. It is necessary to live and to function throughout the day. The type of food we consume is up to us, we can have healthy, nutritious food or we can have quick, unhealthy food. The choice comes down to our knowledge of what we consume and need as humans. Unfortunately fast food has changed how we view food, how convenience is a greater commodity than nutrition and the cost for products. Works Cited Bose, Debopriya. â€Å"Advantages and Disadvantages of Fast Food. † 12 Nov. 2013. Buzzle. Web. Clarke, Nancy. â€Å"Health Risks Involved When Eating Fast Food. † 9 Sep. 2013. Demand Media. Web. Food, Inc. Dir. Robert Kenner. Perf. Michael Pollan, Eric Schlosser, Gary Hirschberg, and Joe Halatin. Magnolia Pictures, 2008. Documentary. Henshaw, Ashley. â€Å"The Major Health Hazards of Fast Food. † 9 Sept. 2013. SymptomFind. Web. Hitti, Miranda. â€Å"Top 11 Reasons for Fast Food’s Popularity. † 12 Nov. 2013. WebMD. Web. Pereira, Mark, David S. Ludwig, Alex I. Kartashov, Cara B. Ebbeling, Linda Van Horn, Martha L. Slattery, David R. Jacobs. â€Å"Fast-food Habits, Weight Gain, and Insulin Resistance (The CARDIA Study): 15-Year Prospective Analysis. † 9 Sept. 2013. 365. 9453(2005): 36-42. Web. 9 Sept. 2013 Martindale, Diane. â€Å"Fast Food is a Major Public Health Hazard 177. 2380. † 2 July 2012. Organic Consumers Association. 9 Sept. 2013. Web. Super-Size Me. Dir. Morgan Spurlock. Perf. Morgan Spurlock, Daryl Isaacs, and Lisa Ganjhu. Kathbur Pictures, 2004. Documentary. University of Minnesota Academic Health Center. â€Å"Fast Food Intake Increases Risk of Diabetes and Heart Disease in Singapore. † ScienceDaily. 9 Sept. 2013. Web. Weiss, Thomas C. â€Å"Associated Health Risks of Eating Fast Foods. †. Disabled World.

Computer Vision Syndrome (CVS) :: Essays Papers

Computer Vision Syndrome (CVS) Abstract: Computers are being used for many different reasons all across the world. Computers are used in the work place for documentation and to keep records of clients. The question that will be answered is how does the computer monitor affect an individual during use? The anatomy of the human eye will be addressed to give the reader a better understanding of how light travels through the eye. Computer Vision Syndrome, also known as (CVS), is an effect of gazing into a monitor for long periods of time, and will be discussed to give the reader a clear illustration of the negative effects of the computer monitor. Computer monitors are used in everywhere in many types of lighting, and workplace lighting is an example that will be discussed. The factors that contribute to CVS will be discussed, the symptoms, and finally ways to prevent CVS will be addressed so that the reader will be aware of what can happen if they are sitting in front of a computer for a long duration. How does the computer monitor affect the individual during use? To answer this question, I will address the structure of the pixel and the anatomy of the eye. The human eye is very complex system that responds to many different types of light waves. The light waves enter through the cornea, which is a curved thin membrane that bends the light that passes through. The pupil is the part of the eye that contracts or dilates in response to a given amount of light. For example, if an individual stands in a well-lit room, then the pupils would be constricted because there is too much light. If that person turns the light off, then the pupils will dilate. They dilate, or become bigger because the eyes want to see what is going on. While an individual type on the keyboard in front of the computer monitor, the pupils act the same as in a lighted room versus as dark room. The images that one sees on a monitor such as graphics are made of small pixels. Pixels are the result of an electron beam striking the phosphors coated rear of the surface of the screen (Watt, 2004). Outside of the pixel is less bright than the center of the pixel (Watt, 2004). It is the pixel, which makes it hard for the eyes to focus.

Impact of Foreign Aid on Poverty and Economic Development in Nigeria

CHAPTER ONE INTRODUCTION This project focuses on the poverty profile in Nigeria, the foreign aids given to the nation to help alleviate poverty and how it affects the economic development of Nigeria. According to the World Bank website, â€Å"poverty is hunger. It is lack of shelter. Poverty is being sick and not being able to see a doctor. It is not being able to go to school, not knowing how to read, and not being able to speak properly. Poverty is not having a job, and is fear for the future, and living one day at a time. It is losing a child to illness brought about by unclean water. And lastly, it is powerlessness, lack of representation and freedom. † Poverty is the inability to achieve a certain minimum standard of living. It is multidimensional, involving not only a lack of income, but also ill- health, illiteracy, lack of access to basic social services, and little opportunity to participate in processes that influence people’s lives. Mollie Orshansky, who developed the poverty measurements used by U. S government states that poverty is â€Å"to be poor is to be deprived of goods and services, and other pleasures that people around us take for granted† (Schwartz, 2005) Poverty is pervasive; as about 1. billion people in the world still live on less than a dollar a day and nearly 850 million people go hungry every night. (World Bank) According to Jhighan (2003), poverty is a misery-go-round plaguing the less developed countries. 1. 1BACKGROUND TO THE STUDY The poverty level in Nigeria; as described by the World Bank (1996) is a paradox tha t contradicts the immense wealth it has. Nigeria is a country endowed with human, agricultural, petroleum, gas and large untapped mineral resources. It earned over US$300 billion from just petroleum during the last three decades of the twentieth century. Rather than recoding remarkable progress in national, socio-economic development, Nigeria has retrogressed to being one of the 25 poorest countries of the 21st century while she was among the richest 50 in the early 70s. Nigeria enjoyed steady economic growth and relative stability in the 1960s and 70s especially with emergence of the mining industries. The per-capita income grew steadily and few people were between the poverty line as the agricultural public and industrial sectors absorbed a highest percentage of the labor force. In the early 1980s, severe economic crisis shook Nigeria bringing along with them real and perceived increases in the level of poverty in the country. This was due to factors such as declining prices of oil, the country’s main export, rises in the real international interest rates that compounded the external debt and subsequent slowing down of economic activities and growth. The major underlying cause of all these was domestic policy mistakes. (Aigbokhan, 2000) In 1980, poverty was regarded as a rural phenomenon but by 1985, it had spread to urban areas. This was due to the high rural urban migration that accompanied the impetus to development generated by oil revenues. Also, the collapse of oil exports income and massive importation of food to meet the production capacity in the agricultural sector severely affected urban dwellers. Economic reforms were introduced by the government in 1986; Structural Adjustment Programme (SAP), which led to the removal of reduction of subsidies that were incidentally strategic to improving human welfare. Government spending on social services became dismal while the quality and quantity of public social services declined, especially in poor communities. Its social costs are reflected in increasing unemployment, cuts in social services, and general increases in the prices of basic commodities. The economic reform programme placed untold hardship on the vulnerable groups of the society such as the women, children and the aged, who make up a larger share of the poor. The standard of living of the general populace fell and led to poor access to food, shelter, education, health and other essentials of life. In 1992, urban poverty remained the same at 37. 5% while rural poverty reduced to 46%. By 1996, it was very obvious that urban poverty had become an increasing problem in Nigeria. For example, the number of people in poverty increased from 27% in 1980 to 46% in 1985. it declined slightly to 42% in 1992, and increased very sharply to 67% in 1996. In 1999, estimates showed that over 70% of Nigerians lived in poverty. The government then declared in November 1999 that the 470 billion naira budget for the year 2000 was â€Å"to relieve poverty. † By 1996, Nigeria had become the 13th poorest country in the world and occupied the 142nd rank on the human development index (HDI) scale. World Bank, 1996) With the reforms, the real growth became positive but there was still a question whether the reform alleviated poverty; how far poverty was reduced. Foreign aid is the economic help provided to communities of countries due to the occurrence of a humanitarian crisis or for the achievement of a socioeconomic objective. There are two types of aids: Humanitarian aid is the i mmediate assistance given to individuals, organizations or government for emergency relief caused by war or natural disasters. Development aid is help given by developed countries to support economic or social development in developing countries so as to create long term sustainable economic growth. The sources of foreign aids include bilateral and multilateral aids. Bilateral aid is given by the government of one country directly to another. Multilateral aid is aid from an international financial institution; such as the World Bank; the International Monetary Fund; the African, Asian and Inter-American Development Banks; the European Development Fund; and various United Nations agencies such as the United Nations Development Programme. These organizations are governed by individual contributing countries and capital markets. Non-governmental Organizations (NGOs) also play a major role in distributing aids. Tied aid is the aid which the donor requires a recipient to spend some or all of its foreign aid on goods and services produced in the donor’s country. This process is called tying of aids. This can also be done by offering aid as subsidized credit for the purchase of its exports. Majority of the NGOs in Nigeria receive foreign aids from USAID (The United States Agency for International Development) USAID is an independent federal agency that receives overall foreign policy guidelines from the United States Secretary of State. It seeks to extend a helping hand to countries struggling for a better life, recovering from a disaster or striving to live. It supports economic growth, agriculture, trade, health, democracy, conflict prevention and humanitarian assistance. Other organizations in Nigeria also receive funds from USAID to undertake projects ranging from HIV/AIDS prevention to bringing solar energy to a rural village. On the other hand, Nigeria is currently not eligible to receive grants through the Millennium Challenge Corporation (MCC), which was established under President Bush as part of the â€Å"new agreement for global development. † Its mission is to reduce global poverty through promotion of sustainable economic growth. Before a country is eligible to receive assistance, MCC looks at their performance on 16 independent and transparent policy indicators. Nigeria is a country, strategically important to the U. S. and a country whose citizens are greatly in need. At the same time, it is a country whose government does not pass the test for receiving aid through the MCC. 1. 2STATEMENT OF PROBLEM Poverty is a persistent problem which has existed for a long time in Nigeria. A lot of policies have been applied to alleviate it but without much success. This research x-rays the contribution of foreign aids as a solution to thi s problem. The specific problems we will look at in this study are the causes of poverty and also how foreign aids can contribute to poverty reduction in the Nigerian economy. . 3OBJECTIVES OF THE STUDY The major objective of this study is to examine the effects of poverty and foreign aids given to us on the development of the economy. The study will focus on other micro objectives, which include: i. To analyze the poverty profile and discuss the national trends of poverty in Nigeria. ii. To review the causes, measures and impact of poverty on the GDP of Nigeria. iii. To identify the forms and roles of the foreign aids given to Nigeria. iv. To identify the relationship between foreign aids and poverty in the Nigerian economy. 4. THEORETICAL FRAMEWORK This study uses the theoretical framework employed by Ogbuaku, Adebisi and Feridun (2006) based on the neoclassical growth model by Barro (1991). It is based on a small open economy version of the Solow (1956)-Swan (1956) growth model. The decision to study foreign aid in an open economy, as opposed to a closed, is three fold. First, most of the economies that receive foreign aid must reasonably be considered small and open. Second, to the extent that international credit markets are imperfect, some forms of foreign aid can have a positive impact on the poor. Third, in our empirical work we provide statistical evidence to suggest that greater international openness and access to credit stimulates economic growth. 5. METHODOLOGY The data for this study will be mainly from secondary sources such as World Bank reports, Central Bank of Nigeria publications such as the CBN Economic and Financial Review Bullions, occasional papers, CBN annual reports and statement of accounts, Federal Office of Statistics (Statistical bulletin) and other relevant journals. This research makes use of econometrics in estimating the relationship between poverty, foreign aids and its contribution to the development of the Nigerian economy. The multiple regression technique is used in obtaining numerical estimates of the variables in different equations. This is because the computational procedure is a component of other estimation techniques. The estimation period will be from 1981 to 2007. 6. MODEL SPECIFICATION This study uses the theoretical framework employed by Ogbuaku, Adebisi and Feridun (2006) based on the neoclassical growth model by Barro (1991). They specify a simple model of poverty and globalization as follows: POV  =     ? 0+1 ? TRADE+ ? 2FDI+  µÃ‚  (1) This model is augmented to include the foreign aid element thus: POV  =      ? 0+ ? 1TRADE+ ? 2FDI + ? 3AID+  µ   Ã‚  Ã‚   (2) Where POV is the yearly average per capita income trade is import + export /gdp fdi is foreign direct investment aid is foreign aid  µ is the stochastic error term 7. RESEARCH QUESTIONS This research aims to answer the following questions: †¢ Has foreign aids flow reduced poverty? †¢ Does foreign aid achieve its basic objectives in its recipient countries? Does foreign aid lead to a positive, negative or no effect on growth and economic development? 8. HYPOTHESIS To carry out this study, the following hypothesis will be tested based on a model to be specified and formulated to determine the relationship between foreign aids and economic development. Hypothesis 1 H0: Foreign aids have no significant impact on the econom ic development of Nigeria. H1: Foreign aids have a significant impact on the economic development of Nigeria. 1. 9SIGNIFICANCE OF THE STUDY This significance of this project can be viewed from the perspective of using foreign aids to alleviate poverty and also develop our economy. It studies the poverty profile of the nation and shows how the proper allocation of foreign aids will help improve the development of our economy. 1. 10SCOPE/ LIMITATION OF THE STUDY The research work attempts to cover the effect of the foreign aids given on the Nigerian economy and its impact on the poverty level in our nation. It focuses on the empirical analysis of the relationship between poverty, foreign aids and inflation in Nigeria. The objectives of this study cannot be achieved without encountering either minor or major problems. The major limitations of the study are those that characterize the use of secondary data. They include errors of improper data collections, errors of omission, the problem of over or under estimation of estimates, etc. 11. CHAPTERIZATION Chapter one contains the introductory part; the background to the study, the statement of the problem, the objective of the study and the methodology used. Chapter two contains the literature review and theoretical framework. Chapter three explains the methodology and also includes the model specification. Chapter four covers the analysis of data. Chapter five discusses the summary and conclusion. 1. 12DEFINITION OF TERMS The key terms in this chapter include: Poverty: is the shortage of common things such as food, clothing, shelter and safe drinking water, all of which determine the quality of our life. Foreign aid: is the help provided to communities in the event of humanitarian crisis, or to achieve a socio economic objective. Economic development: is the qualitative change in economic wants, goods, incentives, institutions, productivity and knowledge or the â€Å"upward movement of the entire social system. † Gross Domestic Product (GDP): is the total final output of goods and services produced by a country’s economy, within the country’s territory. Human Development Index (HDI): is a composite index that ranks all countries based on three fundamental dimensions: longevity, educational attainment and standard of living. CHAPTER TWO LITERATURE REVIEW 2. 1DEFINITION OF POVERTY Poverty comes in the form of deprivation. It is when there is lack of the means to satisfy basic needs. According to the Penguin Dictionary of Economics, poverty is â€Å"the situation faced by people whose material needs are least satisfied†. It also specifies that â€Å"poverty exists not merely because the needs of some low-income households are high. People are poverty – stricken when their living standard falls radically below the community average. This implies that, such people cannot have what the larger society regards as the minimum necessity for decency. Poverty is a living condition characterized by disease, illiteracy, malnutrition and squalor, to the extent that it inhibits the realization of potentials of individuals and even entire societies. It is therefore being regarded to as a socio-economic and political liability to any nation (Ekpo, 2000: 347). The poverty affects all aspects of a person’s life: susceptibility to disease, limited access to most types of services and information, lack of control over resources, subordination to higher social and economic classes, utter insecurity in the face of changing circumstances, including its psychological effect – the erosion of human dignity and self respect. The effects of poverty can not be over emphasized. It results into hunger, diseases, inadequate shelter and homelessness as part of the consequences of poverty. In our contemporary time, the poor man/woman has no voice in the society, lacks political influence, personal recognition; he is often emotionally and psychologically distressed and is always the downtrodden element in the society. (Fasoranti, 2008) 2. 2Concepts of Poverty Poverty is a multifaceted concept that manifests itself in different forms depending on the nature and content of human deprivation. It affects many aspects of human conditions, including; physical, moral and psychological. Poverty is so broad that the literature referring to the efforts of defining and estimating poverty is greater than the one concerning the strategies for overcoming poverty. The concept of poverty answers the question of what is a sufficient degree of needs satisfaction and how it is established. Different criteria have been used to conceptualize poverty. Most analysis view poverty as a result of insufficient income for securing basic goods and services. Others view it as a function of education, life expectancy, health, and child mortality, etc. According to Blackwood and Lynch (1994), poverty can be identified using the criteria of levels of consumption and expenditure. Sen (1983) relates poverty to entitlements, which are taken to be the various bundles of goods and services over which one has command, taking into cognizance the means by which such goods are acquired. Poverty can also arise as a result of inefficient use of common resources which is due to weak policy, environment, inadequate infrastructure, and weak access to technology, credit, etc. Poverty can also be described as structural or transient. Structural poverty (chronic poverty) is defined as persistent or permanent socio-economic deprivations. It is linked to factors such as lack of skills for gainful employment, limited productive resources, gender, endemic socio-political and cultural factors. Transient poverty, on the other hand, is defined as temporary or transitory and is linked to natural and man-made disasters. Transient poverty is more reversible but can become structural if it persists. Poverty was also conceptualized by Steeten and Burki (1978); broadly into four ways. They include: †¢ Lack of access to basic needs or goods; †¢ Lack of or impaired access to productive resources; †¢ Outcome of inefficient use of common resources; and †¢ A result of â€Å"exclusive mechanisms†. 3. CAUSES OF POVERTY Many different factors have been cited to explain why poverty occurs; but none of them has been able to gain universal acceptance. Possible factors include: Economic factors: 1. Recession: In general, the major fluctuations in poverty rates over time are driven by the business cycle. Poverty rates increase in recessions and decline in booms. Extreme recessions, such as the Great Depression have a particularly large impact on poverty. In 1933, 25% of all workers and 37% of all non-farm workers in the United States were unemployed. In New York, one child in every five was hungry. 2. Economic inequality: Even if average income is high, poverty rate will also be high if incomes are distributed unevenly. However the evidence on the relationship between absolute poverty rates and inequality is mixed and ensitive to the inequality index used. For example, while many Sub-Saharan African countries have both high inequality and high poverty rates, other countries, such as India have low inequality and high poverty rates. In general the extent of poverty is much more closely related to average income than it is to the variance in its distribution. At the same time some research indicates that countries which start with a more equitable distribution of income find it easier to eradicate poverty through economic growth. In addition to income inequality, an unequal distribution of land can also contribute to high levels of poverty. 3. Food prices and Poverty: Poor people spend a greater portion of their budgets on food than rich people. As a result poor households and those within the poverty threshold can be particularly vulnerable to increases in food prices. For example in late 2007 increases in the price of grains led to food riots in some countries. Decreases in food prices can also affect poverty although they tend to impact a different group – small farmers – than food price increases. 4. Democracy and Poverty: When we look at social dimensions of development, access to drinking water, girls' literacy, and health care are starkly divergent. For example, in terms of life expectancy, rich democracies typically enjoy life expectancies that are at least nine years longer than poor autocracies. Opportunities of finishing secondary school are 40 percent higher. Infant mortality rates are 25 percent lower. Agricultural yields are about 25 percent higher, on average, in poor democracies than in poor autocracies—an important fact, given that 70 percent of the population in poor countries is often rural-based. Poor democracies don't spend any more on their health and education sectors as a percentage of GDP than do poor autocracies, nor do they get higher levels of foreign assistance. They don't run up higher levels of budget deficits. They simply manage the resources that they have more effectively. † 5. Welfare states and Poverty: Currently modern, expansive welfare states that ensure economic opportunity, independence and security in a near universal manner are still the exclusive domain of the developed nations, ommonly constituting at least 20% of GDP, with the largest Scandinavian welfare states constituting over 40% of GDP. These modern welfare states, which largely arose in the late 19th and early 20th centuries, seeing their greatest expansion in the mid 20th century, and have proven themselves highly effective in reducing relative as well as absolute poverty in all analyzed high-income OECD countries. †¢ The governance effectiveness of governments has a major impact on the delivery of socioeconomic outcomes for poor populations †¢ Weak rule of law can discourage investment and thus perpetuate poverty. Poor management of resource revenues can mean that rather than lifting countries out of poverty, revenues from such activities as oil production or gold mining actually leads to a resource curse. †¢ Failure by governments to provide essential infrastructure worsens poverty. †¢ Poor access to affordable education traps individuals and countries in cycles of poverty. †¢ High levels of corruption undermine efforts to make a sustainable impact on poverty. In Nigeria, for example, more than $400 billion was stolen from the treasury by Nigeria's leaders between 1960 and 1999 (Ribadu,2007) 6. Environmental Degradation: In  many  parts  of  the  world, environmental degradation—the deterioration of the natural environment, including the atmosphere, bodies of water, soil, and forests—is an important cause of poverty. Environmental problems have led to shortages of food, clean water, materials for shelter, and other essential resources. As forests, land, air, and water are degraded, people who live directly off these natural resources suffer most from the effects. People in developed countries, on the other hand, have technologies and conveniences such as air and water filters, efined fuels, and industrially produced and stored foods to buffer themselves from the effects of environmental degradation. Global  environmental  degradation may result from a variety of factors, including overpopulation and the resulting overuse of land and other resources. Intensive farming, for instance, depletes soil fertility, thus decreasing crop yields. Environment al degradation also results from pollution. Polluting industries include mining, power generation, and chemical production. Other major sources of pollution include automobiles and agricultural fertilizers. In  developing  countries, deforestation has had particularly devastating environmental effects. Many rural people, particularly in tropical regions, depend on forests as a source of food and other resources, and deforestation damages or eliminates these supplies. Forests also absorb many pollutants and water from extended rains; without forests, pollution increases and massive flooding further decreases the usability of the deforested areas. 2. 4MEASUREMENT OF POVERTY/INDICATORS Poverty is usually measured as either absolute or relative poverty (the latter is actually an index of income inequality). . 4. 1Absolute poverty: This refers to a set standard which is consistent over time and between countries. An example of an absolute measurement would be the percentage of the population eating less food than is required to sustain the human body (approximately 2000-2500 calories per day for an adult male). The World Bank defines extreme poverty as living on less than US $1. 25 (PPP) per day, and moderate poverty as less than $2 a day. Estimating that in 2001, 1. 1 billion people had consumption levels below $1 a day and 2. 7 billion lived on less than $2 a day. Other absolute poverty indicators include: Life expectancy: According to Encarta encyclopedia, it is the average length of life that would be observed in a population in which the currently prevailing mortality risks at each age continued indefinitely. Infant mortality: Infant mortality rate is the probability of death in the first year of life, usually stated as a number per 1,000 births. 2. 4. 2Relative poverty: According to Wikipedia, relative poverty views poverty as socially defined and dependent on social context, hence relative poverty is a measure of income inequality. Usually, relative poverty is measured as the percentage of population with income less than some fixed proportion of median income. There are several other different income inequality metrics, for example the Gini coefficient or the Theil Index. Relative poverty measures are used as official poverty rates in several developed countries. As such these poverty statistics measure inequality rather than material deprivation or hardship. The measurements are usually based on a person's yearly income and frequently take no account of total wealth. The main poverty line used in the Organization of Economic Cooperation and Development (OECD) and the European Union is based on â€Å"economic distance†, a level of income set at 50% of the median household income. 2. 5Social Aspects of poverty Analysis of social aspects of poverty links conditions of scarcity to aspects of the distribution of resources and power in a society and recognizes that poverty may be a function of the diminished â€Å"capability† of people to live the kinds of lives they value. The social aspects of poverty may include lack of access to information, education, health care, or political power. Poverty may also be understood as an aspect of unequal social status and inequitable social relationships, experienced as social exclusion, dependency, and diminished capacity to participate, or to develop meaningful connections with other people in society. The World Bank's â€Å"Voices of the Poor,† based on research with over 20,000 poor people in 23 countries, identifies a range of factors which poor people identify as part of poverty. These include: †¢ Precarious livelihoods †¢ Excluded locations †¢ Physical limitations †¢ Gender relationships Problems in social relationships †¢ Lack of security †¢ Abuse by those in power †¢ Disempowering institutions †¢ Limited capabilities †¢ Weak community organizations 2. 6 FOREIGN AID The standard definition of foreign aid comes from the Development Assistance Committee (DAC) of the Organization of Economic Cooperation and Development (OECD), which defines foreign aids as financial flows, technical assistance, and commodities that are; designed to promote economic development and welfare as their main objective and are provided as either grants or subsidized loans. . 6. 1Humanitarian aid Humanitarian aid or emergency aid is rapid assistance given to people in immediate distress by individuals, organizations, or governments to relieve suffering, during and after man-made emergencies (like wars) and natural disasters. The term often carries an international connotation, but this is not always the case. It is often distinguished from development aid by being focused on relieving suffering caused by natural disaster or conflict, rather than removing the root causes of poverty or vulnerability. The provision of humanitarian aid consists of the provision of vital services (such as food aid to prevent starvation) by aid agencies, and the provision of funding or in-kind services (like logistics or transport), usually through aid agencies or the government of the affected country. Humanitarian aid is distinguished from humanitarian intervention, which involves armed forces protecting civilians from violent oppression or genocide by state-supported actors. The Geneva Conventions give a mandate to the International Committee of the Red Cross (ICRC) and other impartial humanitarian organizations to provide assistance and protection of civilians during times of war. The ICRC has been given a special role by the Geneva Conventions with respect to the visiting and monitoring of prisoners of war. The United Nations Office for the Coordination of Humanitarian Affairs (OCHA) is mandated to coordinate the international humanitarian response to a natural disaster or complex emergency acting on the basis of the United Nations General Assembly Resolution 46/182. The Sphere Project handbook, Humanitarian Charter and Minimum Standards in Disaster Response, which was produced by a coalition of leading non-governmental humanitarian agencies, lists the following principles of humanitarian action: †¢ The right to life with dignity. †¢ The distinction between combatant and non-combatants. †¢ The principle of non-refoulement. 2. 6. 2Development aid Development aid is aid given by developed countries to support development in general which can be economic development or social development in developing countries. It is distinguished from humanitarian aid as being aimed at alleviating poverty in the long term, rather than alleviating suffering in the short term. The term â€Å"development aid† is often used to refer specifically to Official Development Assistance (ODA), which is aid given by governments on certain concessional terms. It is given by governments through individual countries' international aid agencies and through multilateral institutions such as the World Bank, and by individuals through development charities such as Action Aid, Caritas, Care International or Oxfam. In terms of dollars, the United States has consistently being the world’s largest donor (except in the mid-1990s when Japan briefly topped the list). In 2004, the U. S provided $19. 7 billion in ODA, with Japan, France, the United Kingdom, and Germany as the next largest donors, (including OA, the U. S provided a total of $21. 3 billion). However, when aid is measured as a share of donor income, the most generous donors are Norway, Denmark, Luxembourg, the Netherlands and Sweden, each of which provided between 0. 79- 0. 92% of GDP in 2004. Saudi Arabia provided aid equivalent to about 0. 9% of its income. The United States is one of the smallest donors by this measure at about 0. 17 percent of U. S income in 2004, just over half of the 1970 level of 0. 32% and less than one-third of the U. S average during the 1960s. Donors have pledged since the 1960s to devote 0. 7% of their income as aid, most recently at Financing for Development Conference in Monterrey, Mexico in March 20 02, but only a handful of small donors have achieved this level of aid. The offer to give development aid has to be understood in the context of the Cold War. The speech in which Harry Truman announced the foundation of NATO is also a fundamental document of development policy: â€Å"in addition, we will provide military advice and equipment to free nations which will cooperate with us in the maintenance of peace and security. Fourth, we must embark on a bold new program for making the benefits of our scientific advances and industrial progress available for the improvement and growth of underdeveloped areas. More than half the people of the world are living in conditions approaching misery. Their food is inadequate. They are victims of disease. Their economic life is primitive and stagnant. Their poverty is a handicap and a threat both to them and to more prosperous areas. For the first time in history, humanity possesses the knowledge and skill to relieve the suffering of these people. † 2. 6. 3Specific types of Aid †¢ Project aid: Aid is given for a specific purpose e. g. building materials for a new school. †¢ Programme aid: Aid is given for a specific sector e. g. funding of the education sector of a country. †¢ Budget support: A form of programme aid that is directly channeled into the financial system of the recipient country. †¢ Sector wide Approaches (SWAPs): A combination of Project aid and Programme aid/Budget Support e. . support for the education sector in a country will include both funding of education projects (like school buildings) and provide funds to maintain them (like school books). †¢ Food aid: Food is given to countries in urgent need of food supplies, especially if they have just experienced a natural disaster. â₠¬ ¢ Untied Aid: The country receiving the aid can spend the money as they chose. It improves the government’s inter-temporal fiscal balance. †¢ Tied aid: The aid must be used to purchase products from the country that donated it or a specified group of countries. It always lead to deterioration, thus suggesting a potential tradeoff between consumer welfare and government solvency in the latter case. (Chatterjee and Turnovsky;2005) †¢ Technical assistance: Educated personnel, such as doctors are moved into developing countries to assist with a program of development. Can be both programme and project aid. OECD Categories The Organization for Economic Co-operation and Development's Development Assistance Committee puts foreign aid into three categories: †¢ Official Development Assistance (ODA): is the largest, consisting of aid provided by donor governments to low- and middle- income countries. Official Aid (OA): is aid provided by governments to richer countries with per capita incomes higher than approximately $9000 for three consecutive years; and to countries that were formerly part of the Soviet Union or its satellites. †¢ Other Official Flows (OFF): Aid which does not fall into the other two categories, either because it is not aimed at development, or it consists of more than 75% loan (rather than grant). 2. 7 POVERTY AND ECONOMIC GROWTH The impact on poverty on economic growth is problematic and is not clear. It is indicated that effective anti-poverty action is difficult to achieve largely because the poverty problem is multidimensional, complex and location specific deeply rooted into the social fabric and distribution of economic and political power (Tarp, 2000). One implication of these is that donors as well as analysts of the impact of aid on poverty need to be realistic about the severity of the difficulties that are likely to be encountered and the scale of effort needed to overcome poverty. Most evaluations have shown that achievements in this area are modest at best. In general, it was found that there is a wide gap between the stated commitments to poverty reduction and the actual practices of reducing poverty in the field. Most donors have paid little attention to conceptualization and analysis of poverty and have been particularly weak in translating the poverty reduction objective into operational guidance and in their country assistance strategies. Similar pitfall applies to most analysis of the impact of aid on poverty. The main instruments of donor intervention has been a series of ad hoc projects and in these improvements have been observed over time in respect of participation by beneficiaries and gender sensitivity but few donors have been concerned about sustainability. 2. 8FOREIGN AID AND ECONOMIC GROWTH Most foreign aid is designed to meet one or more of four broad economic and development objectives. †¢ To stimulate economic growth through building infrastructure, supporting productive sectors such as agriculture, or bringing new ideas and technologies; †¢ To strengthen education, health, environmental or political systems; To support subsistence consumption of food and other commodities, especially during relief operations and humanitarian crises; †¢ To help stabilize an economy following economic shocks. Despite these objectives for aid, economic growth has always been the main yardstick used to judge aid’s effectiveness, with more aid expected to lead to faster growt h. But at a broad level, there is no apparent simple relationship between aid and growth. The absence of a simple relationship means that for some observers, it is an evidence of a failure of aid to achieve its basic objectives. But for others, it is misleading, as other factors affect both aid and growth. Not surprisingly, the views on the economic impact of foreign aid on poor countries turn out to be highly divided. Some papers, e. g. Rwabutomize(2008) and Cato Institute (2004)) totally oppose the notion that foreign aid has beneficial effects on developing economies and even go as far as saying they indeed hinder growth. Others like Karras (2006), Durbarry, Gemmell & Greenaway (2004) and Wangwe (2004) find a positive relationship between the two. Yet a lot of research finds conditional relationships between the two variables. This section gives a summary of the views from the examined relevant and available literature on this subject. 2. 9Economic impact of foreign aid in theory The impact of foreign aid on recipient countries’ economies has been a subject of research and debate among scholars and policymakers for more than five decades. There are two obvious stands in the literature of foreign aid effectiveness: one argues that foreign aid spurs growth and development of the recipient countries while the other opposes this view by arguing that aid crowds out savings and investments and thus slows down economic growth. There is also another stand that proposes that foreign aid has a conditional relationship with growth, accelerating growth only under some certain circumstances. A possible reason for the high variability of opinions on the benefits of foreign aid is that there is no generally accepted theory on the workings of foreign aid. Frameworks like the gap theory have been widely criticized in contemporary research leaving the employed frameworks highly subjective. Simon (1987) offers five criteria for economic aid disbursement. First, the recipient person or nation â€Å"needs† the help. Second, the recipient wants the help. Third, the gift will not have bad effects in the long run on the recipient or others. Fourth, the charity will be used more-or-less efficiently rather than largely wastefully or simply to obtain more money in a pyramid scheme. Fifth, the charity will not be useless to the giver. In addition, a lot of the conditional relationship between foreign aid and economic development is premised on differentiation of foreign aid categories. For instance, Annen and Kosempel (2007) differentiate between foreign aid as technical assistance (TA) and non-technical assistance (NTA). They believe that the policies which will be most effective in reducing international income disparities will be the ones that help reduce the productivity gap, and this is exactly what technical assistance is intended to do. They also explained that when foreign aid takes the form of technical assistance, it can have important effects on improving economic conditions in poor countries; at least when it is administered efficiently. Chatterjee and Turnovsky (2005) in their work classified foreign aid into ‘tied’ and ‘untied’. They posit that the link between foreign aid, economic growth, and welfare depends crucially on the mechanism through which a particular aid program, whether tied or untied, is absorbed by the recipient economy. 2. 9. 1Dissenting views On the other hand, the Cato Institute (2004) actually proffers negative economic impact. In their opinion: †¢ There is no correlation between aid and growth. †¢ Aid that goes into a poor policy environment doesn’t work and contributes to debt. †¢ Aid conditioned on market reforms has been a failure. †¢ Countries that have adopted market-oriented policies have done so because of factors unrelated to aid. There is a strong relationship between economic freedom and growth. †¢ Even aid intended to advance market liberalization can produce undesirable results. Such aid takes the pressure off recipient governments and allows them to postpone, rather than promote, necessary but politically difficult reforms. Easterly (2003) cha llenges the growth gap theory usually used to justify increase in foreign aid. He states that the â€Å"financing gap† model in which aid increases investment and that investment increases economic growth has dubious theoretical foundations and numerous empirical failings. It assumes a stable linear relationship between investment and growth over the short to medium term but there are sound reasons to doubt whether the incremental capital-output ratio is constant and thus whether the relationship from investment to growth is linear. A second key assumption of the model in which aid fills a financing gap and allows greater investment is that aid will actually finance investment rather than consumption. This assumption will hold true only if investment is liquidity-constrained and incentives to invest were favourable. Another opponent of the gap theory is Erixon (2005). He carried out a literature analysis of aid and economic growth by examining case studies of countries who have received considerable amounts of aid. He also contends that the reason countries are poor is not that they lack infrastructure; roads, railways, dams, schools or health clinics. Rather, it is because they lack the institutions of the free society: property rights, the rule of law, free markets, and limited government. He maintains that even in the face of sound policy, foreign aid fails to have the desired effect. According to him, there is much evidence supporting the view that aid largely has backed political regimes with little interest in growth and development. It would be much more sensible to scale back the levels of aid considerably; provide aid only to governments that are already reforming and agree to continue reforms; and make clear that aid will be available only for a strictly limited period. M’Amanja & Morrissey (2004), in their study contend with foreign aid–economic growth relationships based on the often wrong theoretical assumptions used as a basis for it. With respect to the stipulations of endogenous growth theory, high investment ratios do not necessarily lead to rapid economic growth; the quality of investment, its productivity, existence of appropriate policy, political, and social infrastructure are all determinants of the effectiveness of investment. Time series was used to investigate this relationship in the Kenyan economy. They focused on one element of growth and used a multivariate approach on time series data for Kenya over the period 1964 – 2002 to investigate the growth effects of foreign aid, investment and a measure of international trade. In addition, some opposition to foreign aid comes from social biases. An example is Mutambara (2008) who claims that although the stated intention is ostensibly to assist the poor economies, most foreign aid benefits the donor countries. The modus operandi has been that the rich West provides financial assistance or loans to poor nations to engage Western consultants or institutions to carry out unsustainable and useless projects on the continent. As a result, there is minimum benefit to the African country while the money is recycled back via western institutions. The Cato Institute (2004) gave its position based on economic freedom. They assert that the greater a country’s economic freedom, the greater its level of prosperity over time. Economic freedom, which includes not only policies, such as free trade and stable money, but also institutions, such as the rule of law and the security of private property rights, does not only increase income. It is also strongly related to improvements in other development indicators such as longevity, access to safe drinking water, lower corruption, and lower poverty rates. Radelet (2006) examines aid magnitudes and who gives and receives aid. It discusses the multiple motivations and objectives of aid, some of which conflict with each other. It then explores the empirical evidence on the relationship between aid and growth, which is divided between research that finds no relationship and research that finds a positive relationship (at least under certain circumstances). It also examines some of the key challenges in making aid more effective, including the principal-agent problem and the related issue of conditionality, and concludes by examining some of the main proposals for improving aid effectiveness. Karras (2006) investigates the relationship between foreign aid and growth in per capita GDP using annual data from the 1960 to 1997 period for a sample of 71 aid-receiving developing economies. More specific studies like Asiedu and Nandwa (2004) focused on whether foreign aid in education has a significant effect on growth. In carrying out their study on the effect of foreign education aid they took into consideration the heterogeneous nature of aid as well as the heterogeneity of aid recipients—they disaggregated the aid data into primary, secondary and higher education, and ran separate regressions for low income and middle income countries. Neanidis and Varvarigos (2005) examined the effects of aid transfers and their degree of volatility (different kinds of variability) on economic growth. They conducted regression analysis for a panel of 74 aid-recipient countries over the time period from 1972 to 1998. Bhandari et al. (2007) carried out a region specific study the effectiveness of foreign aid and foreign direct investment in the Czech Republic, Estonia, Hungary, Latvia, Lithuania and Poland. They used a model that includes the labour force, capital stock, foreign aid and foreign direct investment, and is estimated using pooled annual time series data from 1993 to 2002. Before carrying out the estimation, the time series properties of the data were diagnosed and an error-correction model was developed and estimated using a fixed-effects estimator. Inanga and Mandah (2008) examines the role of two foreign aid financing agencies, Enterprise Development Fund (EDF) and Export Development Programme (EDP), in promoting Zambia’s economic growth in a country study. They assessed and analysed the impact of each of them on the growth and development of different sectors of the Zambian economy. The sector impact analysis included manufacturing, agriculture, transport, and institutional capacities. Al Khaldi (2008) analyses the trend and impact of foreign aid on the economic development of Jordan during the period 1990-2005 using for this purpose different statistical techniques. Chatterjee and Turnovsky (2005) introduced two crucial aspects of this mechanism that have been absent from previous work: the importance of the endogeneity of labor supply as an additional margin through which foreign aid may impact on macroeconomic performance; and the role played by the interaction of labor supply and public capital; and externalities associated with public capital accumulation in determining an economy’s response to a foreign aid shock. They suggest that when donors decide on whether a particular aid program should be tied to an investment activity, careful attention should be paid to the recipient’s opportunities for substitution in production, the elasticity of labour supply, and production externalities. It is perfectly possible for a tied transfer to have a presumably unintended adverse effect on the recipient economy, if that economy is structurally different from what the donor perceived. Durbarry, Gemmell and Greenaway (2004) assessed the impact of foreign aid on growth for a large sample of developing countries. They used an augmented Fischer-Easterly type model and estimated this using both cross-section and panel data techniques. This allowed them to identify not only the ceteris paribus growth effects of aid using an established conditioning set of policy variables, but also to assess the robustness of this set to the inclusion of aid, and other forms of, investment finance among the growth determinants. Annen and Kosempel (2007) tested the hypothesis that the effectiveness of aid depends on its level of fragmentation. The study presented a theoretical growth model for a small open economy that was capable of identifying the appropriate specification required for an aid-growth regression. 2. Empirical findings Annen and Kosempel (2007) found that non technical aid (NTA) has no statistically significant impact on growth; but technical aid (TA) has a positive and significant impact, except in countries where it is highly fragmented. A possible explanation for this result is that the savings rate applied to NTA is low, and therefore most of these resources are used to finance consumption instead of investment. Although the policy interaction term for NTA was found to be positive, as expected; the partial impact of NTA conditional on policy was found not to be statistically significant for any policy level. When aid takes the form of TA our results showed that it has a strong positive and statistically significant impact on economic performance. Specifically, their estimates show that for the average developing economy a 25% increase in TA will lead to about a quarter percentage point increase in its yearly growth rate. Their estimates indicate that when the level of fragmentation is high – above 73%, the partial impact of TA on growth is zero or even negative, depending on the estimation procedure. Asiedu and Nandwa (2004) also gave a conditional aid – growth relationship. They report that the effect of aid varies by income as well as by the type of aid. These results underscore the importance of the heterogeneity of aid flows as well as the heterogeneity of recipient countries when analyzing the effect of aid on growth. Aid depends on the level of development of the recipient country (low and middle income) as well as the level of education at which aid is being targeted (primary, secondary or higher). Aid in primary education enhances growth in low income countries but aid in post-primary education has no significant effect. For middle income countries, aid in primary education and secondary education has an adverse effect on growth but aid in higher education enhances growth. Thus, their results highlight the importance of taking into account the heterogeneity of aid and the heterogeneity of the recipient countries when analyzing aid-growth relationships. Sound policy is another condition given for aid to be beneficial. In the view of Al Khaldi (2008), policies are also important in the effectiveness of the foreign capital inflow, as aid has a more positive impact on growth with good fiscal, monetary and trade policies. In the presence of poor policies, on the other hand, aid has no positive effect on growth. Accordingly, there is a need of not only good policies but also the implementation of these policies as well as the proper monitoring of the aid -utilizing projects is necessary in order to avoid the mis-utilization and the mismanagement of the foreign capital resources. However, according to M’Amanja & Morrissey (2004), aid in the form of net external loans is found to have a significant negative impact on long run growth. Private investment relates to government investment and imports negatively, but positively to foreign aid though they note that the negative association between aid and growth may be due to their use of aid loans rather than grants.. Private investment has been a consistently strong determinant of growth both in the short- and long- run. The implication here is that in order to stimulate and sustain economic growth in Kenya, policy makers need to pay closer attention to factors that determine private investment. However, some findings disregard these conditions and oppose the benefits of foreign aid altogether. The results from Bhandari et al. (2007) indicate that an increase in the stock of domestic capital and inflow of foreign direct investment are significant factors that positively affect economic growth in these countries. Foreign aid did not seem to have any significant effect on real GDP. Rwabutomize (2008) reports that empirical findings reveal that foreign aid has no impact on economic growth amongst the low-income economies under investigation within the Sub-Sahara Africa region from 1990-2004. He concludes that the growth process of poor economies have not benefited from the official development assistance (foreign aid) inflows and increasing aid will not have a positive impact of growth either. Thus these economies should rely on other development resources other than foreign aid such as their domestic savings and tax revenues. Radelet (2006) came up with similar conclusions. Aid can keep bad governments in power for too long, and can undermine incentives for saving, tax collection, and private sector production. Aid relationships are made much more difficult by a complex chain of principal-agent problems that weaken information flows, introduce myriad motivations for different actors, and make monitoring and accountability more difficult. Inanga and Mangah (2008) in their study support these findings. According to them, although Zambia has, on the average, received aid of about US$ 514 million annually over the past three decades, its per capita income has declined from US$1,251 in he early 1970s to about US$ 600 in the late 1990s. They concluded that although it may be difficult to separate the effects of foreign aid finance from those of other growth-inducing factors, efficient and effective utilization of foreign aid finance can contribute to growth in a stable macroeconomic environment. As stated already, not all findings opposed the notion of beneficial foreign aid. The results from Karras (2006) show that the effect of foreign aid on economic growth is positive, permanent, statisticall y signi? ant, and sizable: raising foreign aid by $20 per person of the receiving country results in a permanent increase in the growth rate of real GDP per capita by approximately 0. 16 per cent. Using an alternative foreign-aid measure, a permanent increase in aid by 1 per cent of the receiving economies GDP permanently raises the per capita growth rate by 0. 14 to 0. 26 per cent. Wangwe (2009) states that a survey of three generations of empirical work found a consistent pattern of results. It found that aid increases aggregate savings, aid increases investment and there is a positive relationship between aid and growth in reduced form models. In Durbarry, Gemmell and Greenaway (2004) results vary according to income level, levels of aid allocation and geographical location. They report a positive coefficient on foreign aid as defined by the Organization for Economic Co-operation and Development (FAIDOECD) in 1993 as a percentage of the gross domestic product (GDP), significant at 10%. Point estimates indicate that raising the aid/GDP (or domestic savings/GDP) ratio by one percentage point raises the growth rate by about 0. 10 percentage points. Finally, adopting an alternative measure of foreign aid – aid per capita – yields similar results, confirming a positive and significant impact on growth. Panel data also yields similar results. And lastly according to Neanidis and Varvarigos (2005), on the one hand, devoting aid inflows into productive public spending promotes growth while the related volatility has a damaging effect. On the other hand, the non-productive use of aid transfers has an adverse effect on growth while their volatility is growth-enhancing. They proffer that the general onclusion emerging from their analysis can be summarized as follows: when aid is used productively (unproductively) it has, on average, a positive (negative) effect on growth while its respective volatility has a negative (positive) growth effect. Our results propose that recipient countries should allocate the aid they receive on the most productive uses, while donors should make sure that aid provision is the least erratic p ossible. 2. 10 DEFINITION OF TERMS Economic growth: For the purpose of this study, economic growth will be represented by the annual Gross Domestic Product at current factor cost. Labour force: Labour in this context consists of the number of people aged 15 and over who are employed (that is those who currently have jobs). Individuals who do not fall into either of these groups such as the unemployed, retired people and discouraged workers are not included in the calculation of the labour force. Unemployment: The International Labour Organization (ILO) defines unemployment as the proportion of the labour force which was available for work but did not work for at least one hour in the week preceding the survey period. However, the definition used here is that of the National Bureau of Statistics (NBS), Nigeria. The NBS defines unemployment as the proportion of the labour force that is available for work but did not work for at least 39 hours in the week preceding the survey period. Foreign Aid: is the economic help provided to communities of countries due to the occurrence of a humanitarian crisis or for the achievement of a socioeconomic objective. Foreign direct investment (FDI): FDI is an investment in real assets where real assets consist of physical things such as factories, land, capital goods, infrastructure and inventories. CHAPTER THREE THEORETICAL FRAMEWORK AND METHODOLOGY . 1INTRODUCTION The aim of this study is to examine the relationship between foreign aid and economic growth in Nigeria. This section starts with a theoretical framework then continues with a description of the model to be used for quantitative analysis. The regression is run using Ordinary least squares technique. The theoretical framework of this study is taken from theories, concepts, views and models. 3. 2TH EORETICAL FRAMEWORK This study uses the theoretical framework employed by Ogbuaku, Adebisi and Feridun (2006) based on the neoclassical growth model by Barro (1991). It is based on a small open economy version of the Solow (1956)-Swan (1956) growth model. The decision to study foreign aid in an open economy, as opposed to a closed, is three fold. First, most of the economies that receive foreign aid must reasonably be considered small and open. Second, to the extent that international credit markets are imperfect, some forms of foreign aid can have a positive impact on the poor. Third, in our empirical work we provide statistical evidence to suggest that greater international openness and access to credit stimulates economic growth. The two-gap model can also be employed. The first gap is the gap between the amount of investment necessary to attain a certain growth rate and the available domestic saving. Easterly (2003) examined the investment-savings gap. It goes thus: economic growth depends on investment as a share of GDP, adjusted by a factor that reveals whether investment is of high or poor quality. The amount of investment will be the sum of domestic savings and foreign aid. The model of the â€Å"financing gap† approach thus makes two key assumptions. First, it assumes the above stable linear relationship between investment and growth over the short to medium run. This assumption grows out of a Leontief-style production function with fixed requirements for capital and labour per unit of output. A second key assumption of the model in which aid fills a financing gap and allows greater investment is that aid will actually finance investment rather than consumption. This assumption will hold true only if investment is liquidity-constrained and incentives to invest were favourable. If the cause of low investment is due to poor incentives to invest, then aid will not increase investment. (Easterly, 2003) . 3 RESTATEMENT OF RESEARCH HYPOTHESIS H0: Foreign aid has no significant impact on the reduction of poverty and hence the economic growth of Nigeria. H1: Foreign aid has a significant impact on the reduction of poverty and the economic growth of Nigeria. 3. 4 RESEARH DESIGN 3. 4. 1MODEL SPECIFICATION This study uses the theoretical framework employed by Ogbuaku, Adebisi and Feridun (2006) based on the neoclassical growth model by Barro (1991). The y specify a simple model of poverty and globalization as follows: POV  =     ? 0+1 ? TRADE+ ? FDI+  µÃ¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦(1) This model is augmented to include the foreign aid element thus: POV =      ? 0+ ? 1TRADE+ ? 2FDI + ? 3AID+  µÃ¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦(2) Where POV is the yearly average per capita income trade is import + export /gdp fdi is foreign direct investment aid is foreign aid  µ is the stochastic error term 2. SOURCES OF DATA The analysis will be based on time series data of AID, TRADE, FDI and POV for the Nigerian economy for the period 1981 – 2007. These are secondary data collected from publications of Central Bank of Nigeria such as statistical bulletin and annual reports. 4. METHOD OF DATA ANALYSIS As stated in the introduction to this study, the Ordinary Least Squares (OLS) method of regression analysis is used in this research work. The OLS is one of the most commonly employed and most important methods in estimating relationships in econometrics. Furthermore, to contain the problems associated with time series data, a unit root test; the Augmented Dickey-Fuller (ADF) test, is employed to test for stationarity. Other methods applied include Johansen co-integration and error correction model. 3. 5. 1Augmented Dickey-Fuller (ADF) test Augmented Dickey-Fuller (ADF) test is used to test the stationarity in time series. Stationarity refers to the constancy in mean and variance of time series over a period of time. This will enable us to know if there is co-movement in time series in long run equilibrium. It is the augmented version of the Dickey-Fuller test for a larger and more complicated set of time series model. Stationarity test reveals the presence or absence of random-walk (unit root) in regression analysis. If the time series are non-stationary it means that our regression is spurious and as such estimates cannot be used to predict future values. The time series can then be adjusted in order to make them stationary. The augmented Dickey-Fuller (ADF) statistic used in the test is a negative number. The more negative it is, the stronger the rejections of the hypothesis that there is a unit root at some level of confidence. 3. 5. 2Johansen Co-integration This especially has been developed to overcome the problems of spurious regression which is associated with non-stationary time series data, in such instances, econometric results may not be ideal for policy making. The theory of co-integration arises out of the need to integrate short run dynamics with long run equilibrium. In cases where the data series exhibit the presence of unit roots, short-run dynamics properties of the model can only be captured in an error correction model when the existence of co-integration has been established. On this note, if variable are co-integrated, it shows that such variable possess the capacity to reach equilibrium in the long run. 5. LIMITATIONS TO THE STUDY Using economic growth as a measure of the influence of foreign aid on poverty in Nigeria assumes that there is adequate distribution of wealth in the Nigerian economy such that gains in economic output is transmitted to poor areas. It is possible that this is not the case. In addition, it is necessary to note that the use of regression techniques always comes with limitations. The first is the common warning that correlation does not mean causation. Therefore, even if a relationship is established between the examined variables, this does not guarantee that the occurrence of one necessitates the occurrence of the other. CHAPTER FOUR EMPIRICAL ANALYSIS AND PRESENTATION OF DATA 4. 1 INTRODUCTION In this chapter, the statistical data gathered during the course of this research work is subjected to investigation and analysis. The chapter starts with the brief explanation of various criteria for decision making, followed by the analysis of the static regression equation. In order to test for the presence of unit root (i. e. , spuriousness) in the static regression equation, stationarity test would be conducted using Augmented Dickey Fuller Test (ADF), while co-integration test using Johansen Co-integration test would also be conducted in order to establish the long-run co-movement among the variables. Finally, the error correction model will be used to test the relationships between the variables. . DECISION MAKING CRITERIA The following criteria for decision making are used in the analysis. Coefficient of determination (R2): The R-squa

Database Solutions

DATABASE SOLUTIONS (2nd Edition) THOMAS M CONNOLLY & CAROLYN E BEGG SOLUTIONS TO REVIEW QUESTIONS Chapter 1 Introduction- Review questions 1. 1List four examples of database systems other than those listed in Section 1. 1. Some examples could be: †¢A system that maintains component part details for a car manufacturer; †¢An advertising company keeping details of all clients and adverts placed with them; †¢A training company keeping course information and participants’ details; †¢An organization maintaining all sales order information. 1. 2Discuss the meaning of each of the following terms: (a)dataFor end users, this constitutes all the different values connected with the various objects/entities that are of concern to them. (b)database A shared collection of logically related data (and a description of this data), designed to meet the information needs of an organization. (c)database management system A software system that: enables users to define, create, and maintain the database and provides controlled access to this database. (d)application program A computer program that interacts with the database by issuing an appropriate request (typically an SQL statement) to the DBMS. (e)data independenceThis is essentially the separation of underlying file structures from the programs that operate on them, also called program-data independence. (f)views. A virtual table that does not necessarily exist in the database but is generated by the DBMS from the underlying base tables whenever it’s accessed. These present only a subset of the database that is of particular interest to a user. Views can be customized, for example, field names may change, and they also provide a level of security preventing users from seeing certain data. 1. 3Describe the main characteristics of the database approach.Focus is now on the data first, and then the applications. The structure of the data is now kept separate from the programs that operate on the d ata. This is held in the system catalog or data dictionary. Programs can now share data, which is no longer fragmented. There is also a reduction in redundancy, and achievement of program-data independence. 1. 4Describe the five components of the DBMS environment and discuss how they relate to each other. (1)Hardware:The computer system(s) that the DBMS and the application programs run on. This can range from a single PC, to a single mainframe, to a network of computers. 2)Software:The DBMS software and the application programs, together with the operating system, including network software if the DBMS is being used over a network. (3)Data:The data acts as a bridge between the hardware and software components and the human components. As we’ve already said, the database contains both the operational data and the meta-data (the ‘data about data’). (4)Procedures:The instructions and rules that govern the design and use of the database. This may include instructions on how to log on to the DBMS, make backup copies of the database, and how to handle hardware or software failures. 5)People:This includes the database designers, database administrators (DBAs), application programmers, and the end-users. 1. 5Describe the problems with the traditional two-tier client-server architecture and discuss how these problems were overcome with the three-tier client-server architecture. In the mid-1990s, as applications became more complex and potentially could be deployed to hundreds or thousands of end-users, the client side of this architecture gave rise to two problems: †¢A ‘fat’ client, requiring considerable resources on the client’s computer to run effectively (resources include disk space, RAM, and CPU power). A significant client side administration overhead. By 1995, a new variation of the traditional two-tier client-server model appeared to solve these problems called the three-tier client-server architecture. This new arc hitecture proposed three layers, each potentially running on a different platform: (1)The user interface layer, which runs on the end-user’s computer (the client). (2)The business logic and data processing layer. This middle tier runs on a server and is often called the application server. One application server is designed to serve multiple clients. (3)A DBMS, which stores the data required by the middle tier.This tier may run on a separate server called the database server. The three-tier design has many advantages over the traditional two-tier design, such as: †¢A ‘thin’ client, which requires less expensive hardware. †¢Simplified application maintenance, as a result of centralizing the business logic for many end-users into a single application server. This eliminates the concerns of software distribution that are problematic in the traditional two-tier client-server architecture. †¢Added modularity, which makes it easier to modify or replace o ne tier without affecting the other tiers. Easier load balancing, again as a result of separating the core business logic from the database functions. For example, a Transaction Processing Monitor (TPM) can be used to reduce the number of connections to the database server. (A TPM is a program that controls data transfer between clients and servers in order to provide a consistent environment for Online Transaction Processing (OLTP). ) An additional advantage is that the three-tier architecture maps quite naturally to the Web environment, with a Web browser acting as the ‘thin’ client, and a Web server acting as the application server.The three-tier client server architecture is illustrated in Figure 1. 4. 1. 6Describe the functions that should be provided by a modern full-scale multi-user DBMS. Data Storage, Retrieval and UpdateAuthorization Services A User-Accessible CatalogSupport for Data Communication Transaction SupportIntegrity Services Concurrency Control Servic esServices to Promote Data Independence Recovery ServicesUtility Services 1. 7Of the functions described in your answer to Question 1. 6, which ones do you think would not be needed in a standalone PC DBMS? Provide justification for your answer.Concurrency Control Services – only single user. Authorization Services – only single user, but may be needed if different individuals are to use the DBMS at different times. Utility Services – limited in scope. Support for Data Communication – only standalone system. 1. 8Discuss the advantages and disadvantages of DBMSs. Some advantages of the database approach include control of data redundancy, data consistency, sharing of data, and improved security and integrity. Some disadvantages include complexity, cost, reduced performance, and higher impact of a failure.Chapter 2 The Relational Model – Review questions 2. 1Discuss each of the following concepts in the context of the relational data model: (a)relati on A table with columns and rows. (b)attribute A named column of a relation. (c)domain The set of allowable values for one or more attributes. (d)tuple A record of a relation. (e)relational database. A collection of normalized tables. 2. 2Discuss the properties of a relational table. A relational table has the following properties: †¢The table has a name that is distinct from all other tables in the database. †¢Each cell of the table contains exactly one value. For example, it would be wrong to store several telephone numbers for a single branch in a single cell. In other words, tables don’t contain repeating groups of data. A relational table that satisfies this property is said to be normalized or in first normal form. ) †¢Each column has a distinct name. †¢The values of a column are all from the same domain. †¢The order of columns has no significance. In other words, provided a column name is moved along with the column values, we can interchange c olumns. †¢Each record is distinct; there are no duplicate records. The order of records has no significance, theoretically. 2. 3Discuss the differences between the candidate keys and the primary key of a table. Explain what is meant by a foreign key. How do foreign keys of tables relate to candidate keys? Give examples to illustrate your answer. The primary key is the candidate key that is selected to identify tuples uniquely within a relation. A foreign key is an attribute or set of attributes within one relation that matches the candidate key of some (possibly the same) relation. 2. 4What does a null represent?Represents a value for a column that is currently unknown or is not applicable for this record. 2. 5Define the two principal integrity rules for the relational model. Discuss why it is desirable to enforce these rules. Entity integrityIn a base table, no column of a primary key can be null. Referential integrityIf a foreign key exists in a table, either the foreign key value must match a candidate key value of some record in its home table or the foreign key value must be wholly null. Chapter 3 SQL and QBE – Review questions 3. 1What are the two major components of SQL and what function do they serve?A data definition language (DDL) for defining the database structure. A data manipulation language (DML) for retrieving and updating data. 3. 2Explain the function of each of the clauses in the SELECT statement. What restrictions are imposed on these clauses? FROMspecifies the table or tables to be used; WHEREfilters the rows subject to some condition; GROUP BYforms groups of rows with the same column value; HAVINGfilters the groups subject to some condition; SELECTspecifies which columns are to appear in the output; ORDER BYspecifies the order of the output. 3. What restrictions apply to the use of the aggregate functions within the SELECT statement? How do nulls affect the aggregate functions? An aggregate function can be used only in the SEL ECT list and in the HAVING clause. Apart from COUNT(*), each function eliminates nulls first and operates only on the remaining non-null values. COUNT(*) counts all the rows of a table, regardless of whether nulls or duplicate values occur. 3. 4Explain how the GROUP BY clause works. What is the difference between the WHERE and HAVING clauses? SQL first applies the WHERE clause. Then it conceptually arranges he table based on the grouping column(s). Next, applies the HAVING clause and finally orders the result according to the ORDER BY clause. WHERE filters rows subject to some condition; HAVING filters groups subject to some condition. 3. 5What is the difference between a subquery and a join? Under what circumstances would you not be able to use a subquery? With a subquery, the columns specified in the SELECT list are restricted to one table. Thus, cannot use a subquery if the SELECT list contains columns from more than one table. 3. 6What is QBE and what is the relationship between QBE and SQL?QBE is an alternative, graphical-based, ‘point-and-click’ way of querying the database, which is particularly suited for queries that are not too complex, and can be expressed in terms of a few tables. QBE has acquired the reputation of being one of the easiest ways for non-technical users to obtain information from the database. QBE queries are converted into their equivalent SQL statements before transmission to the DBMS server. Chapter 4 Database Systems Development Lifecycle – Review questions 4. 1Describe what is meant by the term ‘software crisis’.The past few decades has witnessed the dramatic rise in the number of software applications. Many of these applications proved to be demanding, requiring constant maintenance. This maintenance involved correcting faults, implementing new user requirements, and modifying the software to run on new or upgraded platforms. With so much software around to support, the effort spent on maintenan ce began to absorb resources at an alarming rate. As a result, many major software projects were late, over budget, and the software produced was unreliable, difficult to maintain, and performed poorly.This led to what has become known as the ‘software crisis’. Although this term was first used in the late 1960s, more than 30 years later, the crisis is still with us. As a result, some people now refer to the software crisis as the ‘software depression’. 4. 2Discuss the relationship between the information systems lifecycle and the database system development lifecycle. An information system is the resources that enable the collection, management, control, and dissemination of data/information throughout a company. The database is a fundamental component of an information system.The lifecycle of an information system is inherently linked to the lifecycle of the database that supports it. Typically, the stages of the information systems lifecycle include: pla nning, requirements collection and analysis, design (including database design), prototyping, implementation, testing, conversion, and operational maintenance. As a database is a fundamental component of the larger company-wide information system, the database system development lifecycle is inherently linked with the information systems lifecycle. 4. 3Briefly describe the stages of the database system development lifecycle. See Figure 4. Stages of the database system development lifecycle. Database planning is the management activities that allow the stages of the database system development lifecycle to be realized as efficiently and effectively as possible. System definition involves identifying the scope and boundaries of the database system including its major user views. A user view can represent a job role or business application area. Requirements collection and analysis is the process of collecting and analyzing information about the company that is to be supported by the d atabase system, and using this information to identify the requirements for the new system.There are three approaches to dealing with multiple user views, namely the centralized approach, the view integration approach, and a combination of both. The centralized approach involves collating the users’ requirements for different user views into a single list of requirements. A data model representing all the user views is created during the database design stage. The view integration approach involves leaving the users’ requirements for each user view as separate lists of requirements. Data models representing each user view are created and then merged at a later stage of database design.Database design is the process of creating a design that will support the company’s mission statement and mission objectives for the required database. This stage includes the logical and physical design of the database. The aim of DBMS selection is to select a system that meets th e current and future requirements of the company, balanced against costs that include the purchase of the DBMS product and any additional software/hardware, and the costs associated with changeover and training. Application design involves designing the user interface and the application programs that use and process the database.This stage involves two main activities: transaction design and user interface design. Prototyping involves building a working model of the database system, which allows the designers or users to visualize and evaluate the system. Implementation is the physical realization of the database and application designs. Data conversion and loading involves transferring any existing data into the new database and converting any existing applications to run on the new database. Testing is the process of running the database system with the intent of finding errors.Operational maintenance is the process of monitoring and maintaining the system following installation. 4. 4Describe the purpose of creating a mission statement and mission objectives for the required database during the database planning stage. The mission statement defines the major aims of the database system, while each mission objective identifies a particular task that the database must support. 4. 5Discuss what a user view represents when designing a database system. A user view defines what is required of a database system from the perspective of a particular job (such as Manager orSupervisor) or business application area (such as marketing, personnel, or stock control). 4. 6Compare and contrast the centralized approach and view integration approach to managing the design of a database system with multiple user views. An important activity of the requirements collection and analysis stage is deciding how to deal with the situation where there is more than one user view. There are three approaches to dealing with multiple user views: †¢the centralized approach, †¢the view integration approach, and †¢a combination of both approaches.Centralized approach Requirements for each user view are merged into a single list of requirements for the new database system. A logical data model representing all user views is created during the database design stage. The centralized approach involves collating the requirements for different user views into a single list of requirements. A data model representing all user views is created in the database design stage. A diagram representing the management of user views 1 to 3 using the centralized approach is shown in Figure 4. 4.Generally, this approach is preferred when there is a significant overlap in requirements for each user view and the database system is not overly complex. See Figure 4. 4 The centralized approach to managing multiple user views 1 to 3. View integration approach Requirements for each user view remain as separate lists. Data models representing each user view are created and then mer ged later during the database design stage. The view integration approach involves leaving the requirements for each user view as separate lists of requirements.We create data models representing each user view. A data model that represents a single user view is called a local logical data model. We then merge the local data models to create a global logical data model representing all user views of the company. A diagram representing the management of user views 1 to 3 using the view integration approach is shown in Figure 4. 5. Generally, this approach is preferred when there are significant differences between user views and the database system is sufficiently complex to justify dividing the work into more manageable parts.See Figure 4. 5 The view integration approach to managing multiple user views 1 to 3. For some complex database systems it may be appropriate to use a combination of both the centralized and view integration approaches to managing multiple user views. For examp le, the requirements for two or more users views may be first merged using the centralized approach and then used to create a local logical data model. (Therefore in this situation the local data model represents not just a single user view but the number of user views merged using the centralized approach).The local data models representing one or more user views are then merged using the view integration approach to form the global logical data model representing all user views. 4. 7Explain why it is necessary to select the target DBMS before beginning the physical database design phase. Database design is made up of two main phases called logical and physical design. During logical database design, we identify the important objects that need to be represented in the database and the relationships between these objects.During physical database design, we decide how the logical design is to be physically implemented (as tables) in the target DBMS. Therefore it is necessary to have selected the target DBMS before we are able to proceed to physical database design. See Figure 4. 1 Stages of the database system development lifecycle. 4. 8Discuss the two main activities associated with application design. The database and application design stages are parallel activities of the database system development lifecycle. In most cases, we cannot complete the application design until the design of the database itself has taken place.On the other hand, the database exists to support the applications, and so there must be a flow of information between application design and database design. The two main activities associated with the application design stage is the design of the user interface and the application programs that use and process the database. We must ensure that all the functionality stated in the requirements specifications is present in the application design for the database system. This involves designing the interaction between the user and the data, w hich we call transaction design.In addition to designing how the required functionality is to be achieved, we have to design an appropriate user interface to the database system. 4. 9Describe the potential benefits of developing a prototype database system. The purpose of developing a prototype database system is to allow users to use the prototype to identify the features of the system that work well, or are inadequate, and if possible to suggest improvements or even new features for the database system. In this way, we can greatly clarify the requirements and evaluate the feasibility of a particular system design.Prototypes should have the major advantage of being relatively inexpensive and quick to build. 4. 10Discuss the main activities associated with the implementation stage. The database implementation is achieved using the Data Definition Language (DDL) of the selected DBMS or a graphical user interface (GUI), which provides the same functionality while hiding the low-level DDL statements. The DDL statements are used to create the database structures and empty database files. Any specified user views are also implemented at this stage.The application programs are implemented using the preferred third or fourth generation language (3GL or 4GL). Parts of these application programs are the database transactions, which we implement using the Data Manipulation Language (DML) of the target DBMS, possibly embedded within a host programming language, such as Visual Basic (VB), VB. net, Python, Delphi, C, C++, C#, Java, COBOL, Fortran, Ada, or Pascal. We also implement the other components of the application design such as menu screens, data entry forms, and reports.Again, the target DBMS may have its own fourth generation tools that allow rapid development of applications through the provision of non-procedural query languages, reports generators, forms generators, and application generators. Security and integrity controls for the application are also impleme nted. Some of these controls are implemented using the DDL, but others may need to be defined outside the DDL using, for example, the supplied DBMS utilities or operating system controls. 4. 11Describe the purpose of the data conversion and loading stage.This stage is required only when a new database system is replacing an old system. Nowadays, it’s common for a DBMS to have a utility that loads existing files into the new database. The utility usually requires the specification of the source file and the target database, and then automatically converts the data to the required format of the new database files. Where applicable, it may be possible for the developer to convert and use application programs from the old system for use by the new system. 4. 2Explain the purpose of testing the database system. Before going live, the newly developed database system should be thoroughly tested. This is achieved using carefully planned test strategies and realistic data so that the entire testing process is methodically and rigorously carried out. Note that in our definition of testing we have not used the commonly held view that testing is the process of demonstrating that faults are not present. In fact, testing cannot show the absence of faults; it can show only that software faults are present.If testing is conducted successfully, it will uncover errors in the application programs and possibly the database structure. As a secondary benefit, testing demonstrates that the database and the application programs appear to be working according to their specification and that performance requirements appear to be satisfied. In addition, metrics collected from the testing stage provides a measure of software reliability and software quality. As with database design, the users of the new system should be involved in the testing process.The ideal situation for system testing is to have a test database on a separate hardware system, but often this is not available. I f real data is to be used, it is essential to have backups taken in case of error. Testing should also cover usability of the database system. Ideally, an evaluation should be conducted against a usability specification. Examples of criteria that can be used to conduct the evaluation include (Sommerville, 2000): †¢Learnability – How long does it take a new user to become productive with the system? Performance – How well does the system response match the user’s work practice? †¢Robustness – How tolerant is the system of user error? †¢Recoverability – How good is the system at recovering from user errors? †¢Adapatability – How closely is the system tied to a single model of work? Some of these criteria may be evaluated in other stages of the lifecycle. After testing is complete, the database system is ready to be ‘signed off’ and handed over to the users. 4. 13What are the main activities associated with oper ational maintenance stage.In this stage, the database system now moves into a maintenance stage, which involves the following activities: †¢Monitoring the performance of the database system. If the performance falls below an acceptable level, the database may need to be tuned or reorganized. †¢Maintaining and upgrading the database system (when required). New requirements are incorporated into the database system through the preceding stages of the lifecycle. Chapter 5 Database Administration and Security – Review questions 5. 1Define the purpose and tasks associated with data administration and database administration.Data administration is the management and control of the corporate data, including database planning, development and maintenance of standards, policies and procedures, and logical database design. Database administration is the management and control of the physical realization of the corporate database system, including physical database design and implementation, setting security and integrity controls, monitoring system performance, and reorganizing the database as necessary. 5. 2Compare and contrast the main tasks carried out by the DA and DBA.The Data Administrator (DA) and Database Administrator (DBA) are responsible for managing and controlling the activities associated with the corporate data and the corporate database, respectively. The DA is more concerned with the early stages of the lifecycle, from planning through to logical database design. In contrast, the DBA is more concerned with the later stages, from application/physical database design to operational maintenance. Depending on the size and complexity of the organization and/or database system the DA and DBA can be the responsibility of one or more people. . 3Explain the purpose and scope of database security. Security considerations do not only apply to the data held in a database. Breaches of security may affect other parts of the system, which may in turn affect the database. Consequently, database security encompasses hardware, software, people, and data. To effectively implement security requires appropriate controls, which are defined in specific mission objectives for the system. This need for security, while often having been neglected or overlooked in the past, is now increasingly recognized by organizations.The reason for this turn-around is due to the increasing amounts of crucial corporate data being stored on computer and the acceptance that any loss or unavailability of this data could be potentially disastrous. 5. 4List the main types of threat that could affect a database system, and for each, describe the possible outcomes for an organization. Figure 5. 1 A summary of the potential threats to computer systems. 5. 5Explain the following in terms of providing security for a database: authorization; views; backup and recovery; integrity; encryption; RAID. AuthorizationAuthorization is the granting of a right or privilege t hat enables a subject to have legitimate access to a system or a system’s object. Authorization controls can be built into the software, and govern not only what database system or object a specified user can access, but also what the user may do with it. The process of authorization involves authentication of a subject requesting access to an object, where ‘subject’ represents a user or program and ‘object’ represents a database table, view, procedure, trigger, or any other object that can be created within the database system. ViewsA view is a virtual table that does not necessarily exist in the database but can be produced upon request by a particular user, at the time of request. The view mechanism provides a powerful and flexible security mechanism by hiding parts of the database from certain users. The user is not aware of the existence of any columns or rows that are missing from the view. A view can be defined over several tables with a user being granted the appropriate privilege to use it, but not to use the base tables. In this way, using a view is more restrictive than simply having certain privileges granted to a user on the base table(s).Backup and recovery Backup is the process of periodically taking a copy of the database and log file (and possibly programs) onto offline storage media. A DBMS should provide backup facilities to assist with the recovery of a database following failure. To keep track of database transactions, the DBMS maintains a special file called a log file (or journal) that contains information about all updates to the database. It is always advisable to make backup copies of the database and log file at regular intervals and to ensure that the copies are in a secure location.In the event of a failure that renders the database unusable, the backup copy and the details captured in the log file are used to restore the database to the latest possible consistent state. Journaling is the process of keeping and maintaining a log file (or journal) of all changes made to the database to enable recovery to be undertaken effectively in the event of a failure. Integrity constraints Contribute to maintaining a secure database system by preventing data from becoming invalid, and hence giving misleading or incorrect results. EncryptionIs the encoding of the data by a special algorithm that renders the data unreadable by any program without the decryption key. If a database system holds particularly sensitive data, it may be deemed necessary to encode it as a precaution against possible external threats or attempts to access it. Some DBMSs provide an encryption facility for this purpose. The DBMS can access the data (after decoding it), although there is degradation in performance because of the time taken to decode it. Encryption also protects data transmitted over communication lines.There are a number of techniques for encoding data to conceal the information; some are termed irreve rsible and others reversible. Irreversible techniques, as the name implies, do not permit the original data to be known. However, the data can be used to obtain valid statistical information. Reversible techniques are more commonly used. To transmit data securely over insecure networks requires the use of a cryptosystem, which includes: †¢an encryption key to encrypt the data (plaintext); †¢an encryption algorithm that, with the encryption key, transforms the plain text into ciphertext; †¢a decryption key to decrypt the ciphertext; a decryption algorithm that, with the decryption key, transforms the ciphertext back into plain text. Redundant Array of Independent Disks (RAID) RAID works by having a large disk array comprising an arrangement of several independent disks that are organized to improve reliability and at the same time increase performance. The hardware that the DBMS is running on must be fault-tolerant, meaning that the DBMS should continue to operate even if one of the hardware components fails. This suggests having redundant components that can be seamlessly integrated into the working system whenever there is one or more component failures.The main hardware components that should be fault-tolerant include disk drives, disk controllers, CPU, power supplies, and cooling fans. Disk drives are the most vulnerable components with the shortest times between failures of any of the hardware components. One solution is the use of Redundant Array of Independent Disks (RAID) technology. RAID works by having a large disk array comprising an arrangement of several independent disks that are organized to improve reliability and at the same time increase performance. Chapter 6 Fact-Finding – Review questions 6. Briefly describe what the process of fact-finding attempts to achieve for a database developer. Fact-finding is the formal process of using techniques such as interviews and questionnaires to collect facts about systems, requiremen ts, and preferences. The database developer uses fact-finding techniques at various stages throughout the database systems lifecycle to capture the necessary facts to build the required database system. The necessary facts cover the business and the users of the database system, including the terminology, problems, opportunities, constraints, requirements, and priorities.These facts are captured using fact-finding techniques. 6. 2Describe how fact-finding is used throughout the stages of the database system development lifecycle. There are many occasions for fact-finding during the database system development lifecycle. However, fact-finding is particularly crucial to the early stages of the lifecycle, including the database planning, system definition, and requirements collection and analysis stages. It’s during these early stages that the database developer learns about the terminology, problems, opportunities, constraints, requirements, and priorities of the business and t he users of the system.Fact-finding is also used during database design and the later stages of the lifecycle, but to a lesser extent. For example, during physical database design, fact-finding becomes technical as the developer attempts to learn more about the DBMS selected for the database system. Also, during the final stage, operational maintenance, fact-finding is used to determine whether a system requires tuning to improve performance or further developed to include new requirements. 6. 3For each stage of the database system development lifecycle identify examples of the facts captured and the documentation produced. . 4A database developer normally uses several fact-finding techniques during a single database project. The five most commonly used techniques are examining documentation, interviewing, observing the business in operation, conducting research, and using questionnaires. Describe each fact-finding technique and identify the advantages and disadvantages of each. Exa mining documentation can be useful when you’re trying to gain some insight as to how the need for a database arose.You may also find that documentation can be helpful to provide information on the business (or part of the business) associated with the problem. If the problem relates to the current system there should be documentation associated with that system. Examining documents, forms, reports, and files associated with the current system, is a good way to quickly gain some understanding of the system. Interviewing is the most commonly used, and normally most useful, fact-finding technique. You can interview to collect information from individuals face-to-face.There can be several objectives to using interviewing such as finding out facts, checking facts, generating user interest and feelings of involvement, identifying requirements, and gathering ideas and opinions. Observation is one of the most effective fact-finding techniques you can use to understand a system. With this technique, you can either par ¬ticipate in, or watch a person perform activities to learn about the system. This technique is particularly useful when the validity of data collected through other methods is in question or when the complexity of certain aspects of the system prevents a clear explanation by the end-users.A useful fact-finding technique is to research the application and prob ¬lem. Computer trade journals, reference books, and the Internet are good sources of information. They can provide you with information on how others have solved similar prob ¬lems, plus you can learn whether or not software packages exist to solve your problem. Another fact-finding technique is to conduct surveys through questionnaires. Questionnaires are special-purpose documents that allow you to gather facts from a large number of people while maintaining some control over their responses.When dealing with a large audience, no other fact-finding technique can tabulate the same facts as efficiently. 6. 5Describe the purpose of defining a mission statement and mission objectives for a database system. The mission statement defines the major aims of the database system. Those driving the database project within the business (such as the Director and/or owner) normally define the mission statement. A mission statement helps to clarify the purpose of the database project and provides a clearer path towards the efficient and effective creation of the required database system.Once the mission statement is defined, the next activity involves identifying the mission objectives. Each mission objective should identify a particular task that the database must support. The assumption is that if the database supports the mission objectives then the mission statement should be met. The mission statement and objectives may be accompanied with additional information that specifies, in general terms, the work to be done, the resources with which to do it, and the money to pay f or it all. 6. 6What is the purpose of the systems definition stage?The purpose of the system definition stage is to identify the scope and boundary of the database system and its major user views. Defining the scope and boundary of the database system helps to identify the main types of data mentioned in the interviews and a rough guide as to how this data is related. A user view represents the requirements that should be supported by a database system as defined by a particular job role (such as Manager or Assistant) or business application area (such as video rentals or stock control). 6. How do the contents of a users’ requirements specification differ from a systems specification? There are two main documents created during the requirements collection and analysis stage, namely the users’ requirements specification and the systems specification. The users’ requirements specification describes in detail the data to be held in the database and how the data is to be used. The systems specification describes any features to be included in the database system such as the required performance and the levels of security. 6. Describe one approach to deciding whether to use centralized, view integration, or a combination of both when developing a database system for multiple user views. One way to help you make a decision whether to use the centralized, view integration, or a combination of both approaches to manage multiple user views is to examine the overlap in terms of the data used between the user views identified during the system definition stage. It’s difficult to give precise rules as to when it’s appropriate to use the centralized or view integration approaches.As the database developer, you should base your decision on an assessment of the complexity of the database system and the degree of overlap between the various user views. However, whether you use the centralized or view integration approach or a mixture of both to build the underlying database, ultimately you need to create the original user views for the working database system. Chapter 7 Entity-Relationship Modeling – Review questions 7. 1Describe what entities represent in an ER model and provide examples of entities with a physical or conceptual existence.Entity is a set of objects with the same properties, which are identified by a user or company as having an independent existence. Each object, which should be uniquely identifiable within the set, is called an entity occurrence. An entity has an independent existence and can represent objects with a physical (or ‘real’) existence or objects with a conceptual (or ‘abstract’) existence. 7. 2Describe what relationships represent in an ER model and provide examples of unary, binary, and ternary relationships.Relationship is a set of meaningful associations among entities. As with entities, each association should be uniquely identifiable within the set. A uniquely identifiable association is called a relationship occurrence. Each relationship is given a name that describes its function. For example, the Actor entity is associated with the Role entity through a relationship called Plays, and the Role entity is associated with the Video entity through a relationship called Features. The entities involved in a particular relationship are referred to as participants.The number of participants in a relationship is called the degree and indicates the number of entities involved in a relationship. A relationship of degree one is called unary, which is commonly referred to as a recursive relationship. A unary relationship describes a relationship where the same entity participates more than once in different roles. An example of a unary relationship is Supervises, which represents an association of staff with a supervisor where the supervisor is also a member of staff.In other words, the Staff entity participates twice in the Supervises re lationship; the first participation as a supervisor, and the second participation as a member of staff who is supervised (supervisee). See Figure 7. 5 for a diagrammatic representation of the Supervises relationship. A relationship of degree two is called binary. A relationship of a degree higher than binary is called a complex relationship. A relationship of degree three is called ternary. An example of a ternary relationship is Registers with three participating entities, namely Branch, Staff, and Member.The purpose of this relationship is to represent the situation where a member of staff registers a member at a particular branch, allowing for members to register at more than one branch, and members of staff to move between branches. Figure 7. 4 Example of a ternary relationship called Registers. 7. 3Describe what attributes represent in an ER model and provide examples of simple, composite, single-value, multi-value, and derived attributes. An attribute is a property of an entit y or a relationship. Attributes represent what we want to know about entities.For example, a Video entity may be described by the catalogNo, title, category, dailyRental, and price attributes. These attributes hold values that describe each video occurrence, and represent the main source of data stored in the database. Simple attribute is an attribute composed of a single component. Simple attributes cannot be further subdivided. Examples of simple attributes include the category and price attributes for a video. Composite attribute is an attribute composed of multiple components. Composite attributes can be further divided to yield smaller components with an independent existence.For example, the name attribute of the Member entity with the value ‘Don Nelson’ can be subdivided into fName (‘Don’) and lName (‘Nelson’). Single-valued attribute is an attribute that holds a single value for an entity occurrence. The majority of attributes are singl e-valued for a particular entity. For example, each occurrence of the Video entity has a single-value for the catalogNo attribute (for example, 207132), and therefore the catalogNo attribute is referred to as being single-valued. Multi-valued attribute is an attribute that holds multiple values for an entity occurrence.Some attributes have multiple values for a particular entity. For example, each occurrence of the Video entity may have multiple values for the category attribute (for example, ‘Children’ and ‘Comedy’), and therefore the category attribute in this case would be multi-valued. A multi-valued attribute may have a set of values with specified lower and upper limits. For example, the category attribute may have between one and three values. Derived attribute is an attribute that represents a value that is derivable from the value of a related attribute, or set of attributes, not necessarily in the same entity.Some attributes may be related for a p articular entity. For example, the age of a member of staff (age) is derivable from the date of birth (DOB) attribute, and therefore the age and DOB attributes are related. We refer to the age attribute as a derived attribute, the value of which is derived from the DOB attribute. 7. 4Describe what multiplicity represents for a relationship. Multiplicity is the number of occurrences of one entity that may relate to a single occurrence of an associated entity. 7. 5What are business rules and how does multiplicity model these constraints?Multiplicity constrains the number of entity occurrences that relate to other entity occurrences through a particular relationship. Multiplicity is a representation of the policies established by the user or company, and is referred to as a business rule. Ensuring that all appropriate business rules are identified and represented is an important part of modeling a company. The multiplicity for a binary relationship is generally referred to as one-to-on e (1:1), one-to-many (1:*), or many-to-many (*:*). Examples of three types of relationships include: †¢A member of staff manages a branch. A branch has members of staff. †¢Actors play in videos. 7. 6How does multiplicity represent both the cardinality and the participation constraints on a relationship? Multiplicity actually consists of two separate constraints known as cardinality and participation. Cardinality describes the number of possible relationships for each participating entity. Participation determines whether all or only some entity occurrences participate in a relationship. The cardinality of a binary relationship is what we have been referring to as one-to-one, one-to-many, and many-to-many.A participation constraint represents whether all entity occurrences are involved in a particular relationship (mandatory participation) or only some (optional participation). The cardinality and participation constraints for the Staff Manages Branch relationship are shown in Figure 7. 11. 7. 7Provide an example of a relationship with attributes. An example of a relationship with an attribute is the relationship called PlaysIn, which associates the Actor and Video entities. We may wish to record the character played by an actor in a given video.This information is associated with the PlaysIn relationship rather than the Actor or Video entities. We create an attribute called character to store this information and assign it to the PlaysIn relationship, as illustrated in Figure 7. 12. Note, in this figure the character attribute is shown using the symbol for an entity; however, to distinguish between a relationship with an attribute and an entity, the rectangle representing the attribute is associated with the relationship using a dashed line. Figure 7. 12 A relationship called PlaysIn with an attribute called character. . 8Describe how strong and weak entities differ and provide an example of each. We can classify entities as being either strong or we ak. A strong entity is not dependent on the existence of another entity for its primary key. A weak entity is partially or wholly dependent on the existence of another entity, or entities, for its primary key. For example, as we can distinguish one actor from all other actors and one video from all other videos without the existence of any other entity, Actor and Video are referred to as being strong entities.In other words, the Actor and Video entities are strong because they have their own primary keys. An example of a weak entity called Role, which represents characters played by actors in videos. If we are unable to uniquely identify one Role entity occurrence from another without the existence of the Actor and Video entities, then Role is referred to as being a weak entity. In other words, the Role entity is weak because it has no primary key of its own. Figure 7. 6 Diagrammatic representation of attributes for the Video, Role, and Actor entities.Strong entities are sometimes r eferred to as parent, owner, or dominant entities and weak entities as child, dependent, or subordinate entities. 7. 9Describe how fan and chasm traps can occur in an ER model and how they can be resolved. Fan and chasm traps are two types of connection traps that can occur in ER models. The traps normally occur due to a misinterpretation of the meaning of certain relationships. In general, to identify connection traps we must ensure that the meaning of a relationship (and the business rule that it represents) is fully understood and clearly defined.If we don’t understand the relationships we may create a model that is not a true representation of the ‘real world’. A fan trap may occur when two entities have a 1:* relationship that fan out from a third entity, but the two entities should have a direct relationship between them to provide the necessary information. A fan trap may be resolved through the addition of a direct relationship between the two entities th at were originally separated by the third entity. A chasm trap may occur when an ER model suggests the existence of a relationship between entities, but the pathway does not exist between certain entity occurrences.More specifically, a chasm trap may occur where there is a relationship with optional participation that forms part of the pathway between the entities that are related. Again, a chasm trap may be resolved by the addition of a direct relationship between the two entities that were originally related through a pathway that included optional participation. Chapter 8 Normalization – Review questions 8. 1Discuss how normalization may be used in database design. Normalization can be used in database design in two ways: the first is to use ormalization as a bottom-up approach to database design; the second is to use normalization in conjunction with ER modeling. Using normalization as a bottom-up approach involves analyzing the associations between attributes and, based on this analysis, grouping the attributes together to form tables that represent entities and relationships. However, this approach becomes difficult with a large number of attributes, where it’s difficult to establish all the important associations between the attributes. Alternatively, you can use a top-down approach to database design.In this approach, we use ER modeling to create a data model that represents the main entities and relationships. We then translate the ER model into a set of tables that represents this data. It’s at this point that we use normalization to check whether the tables are well designed. 8. 2Describe the types of update anomalies that may occur on a table that has redundant data. Tables that have redundant data may have problems called update anomalies, which are classified as insertion, deletion, or modification anomalies. See Figure 8. 2 for an example of a table with redundant data called StaffBranch.There are two main types of insertion anomalies, which we illustrate using this table. Insertion anomalies (1)To insert the details of a new member of staff located at a given branch into the StaffBranch table, we must also enter the correct details for that branch. For example, to insert the details of a new member of staff at branch B002, we must enter the correct details of branch B002 so that the branch details are consistent with values for branch B002 in other records of the StaffBranch table. The data shown in the StaffBranch table is also shown in the Staff and Branch tables shown in Figure 8. 1.These tables do have redundant data and do not suffer from this potential inconsistency, because for each staff member we only enter the appropriate branch number into the Staff table. In addition, the details of branch B002 are recorded only once in the database as a single record in the Branch table. (2)To insert details of a new branch that currently has no members of staff into the StaffBranch table, it’s nec essary to enter nulls into the staff-related columns, such as staffNo. However, as staffNo is the primary key for the StaffBranch table, attempting to enter nulls for staffNo violates entity integrity, and is not allowed.The design of the tables shown in Figure 8. 1 avoids this problem because new branch details are entered into the Branch table separately from the staff details. The details of staff ultimately located at a new branch can be entered into the Staff table at a later date. Deletion anomalies If we delete a record from the StaffBranch table that represents the last member of staff located at a branch, the details about that branch are also lost from the database. For example, if we delete the record for staff Art Peters (S0415) from the StaffBranch table, the details relating to branch B003 are lost from the database.The design of the tables in Figure 8. 1 avoids this problem because branch records are stored separately from staff records and only the column branchNo re lates the two tables. If we delete the record for staff Art Peters (S0415) from the Staff table, the details on branch B003 in the Branch table remain unaffected. Modification anomalies If we want to change the value of one of the columns of a particular branch in the StaffBranch table, for example the telephone number for branch B001, we must update the records of all staff located at that branch.If this modification is not carried out on all the appropriate records of the StaffBranch table, the database will become inconsistent. In this example, branch B001 would have different telephone numbers in different staff records. The above examples illustrate that the Staff and Branch tables of Figure 8. 1 have more desirable properties than the StaffBranch table of Figure 8. 2. In the following sections, we examine how normal forms can be used to formalize the identification of tables that have desirable properties from those that may potentially suffer from update anomalies. . 3Describ e the characteristics of a table that violates first normal form (1NF) and then describe how such a table is converted to 1NF. The rule for first normal form (1NF) is a table in which the intersection of every column and record contains only one value. In other words a table that contains more than one atomic value in the intersection of one or more column for one or more records is not in 1NF. The non 1NF table can be converted to 1NF by restructuring original table by removing the column with the multi-values along with a copy of the primary key to create a new table.See Figure 8. 4 for an example of this approach. The advantage of this approach is that the resultant tables may be in normal forms later that 1NF. 8. 4What is the minimal normal form that a relation must satisfy? Provide a definition for this normal form. Only first normal form (1NF) is critical in creating appropriate tables for relational databases. All the subsequent normal forms are optional. However, to avoid th e update anomalies discussed in Section 8. 2, it’s normally recommended that you proceed to third normal form (3NF).First normal form (1NF) is a table in which the intersection of every column and record contains only one value. 8. 5Describe an approach to converting a first normal form (1NF) table to second normal form (2NF) table(s). Second normal form applies only to tables with composite primary keys, that is, tables with a primary key composed of two or more columns. A 1NF table with a single column primary key is automatically in at least 2NF. A second normal form (2NF) is a table that is already in 1NF and in which the values in each non-primary-key column can be worked out from the values in all the columns that makes up the primary key.A table in 1NF can be converted into 2NF by removing the columns that can be worked out from only part of the primary key. These columns are placed in a new table along with a copy of the part of the primary key that they can be worked out from. 8. 6Describe the characteristics of a table in second normal form (2NF). Second normal form (2NF) is a table that is already in 1NF and in which the values in each non-primary-key column can only be worked out from the values in all the columns that make up the primary key. 8. Describe what is meant by full functional dependency and describe how this type of dependency relates to 2NF. Provide an example to illustrate your answer. The formal definition of second normal form (2NF) is a table that is in first normal form and every non-primary-key column is fully functionally dependent on the primary key. Full functional dependency indicates that if A and B are columns of a table, B is fully functionally dependent on A, if B is not dependent on any subset of A. If B is dependent on a subset of A, this is referred to as a partial dependency.If a partial dependency exists on the primary key, the table is not in 2NF. The partial dependency must be removed for a table to achieve 2NF. See Section 8. 4 for an example. 8. 8Describe the characteristics of a table in third normal form (3NF). Third normal form (3NF) is a table that is already in 1NF and 2NF, and in which the values in all non-primary-key columns can be worked out from only the primary key (or candidate key) column(s) and no other columns. 8. 9Describe what is meant by transitive dependency and describe how this type of dependency relates to 3NF. Provide an example to illustrate your answer.The formal definition for third normal form (3NF) is a table that is in first and second normal forms and in which no non-primary-key column is transitively dependent on the primary key. Transitive dependency is a type of functional dependency that occurs when a particular type of relationship holds between columns of a table. For example, consider a table with columns A, B, and C. If B is functionally dependent on A (A ? B) and C is functionally dependent on B (B ? C), then C is transitively dependent on A via B (provided that A is not functionally dependent on B or C).If a transitive dependency exists on the primary key, the table is not in 3NF. The transitive dependency must be removed for a table to achieve 3NF. See Section 8. 5 for an example. Chapter 9 Logical Database Design – Step 1- Review questions 9. 1Describe the purpose of a design methodology. A design methodology is a structured approach that uses procedures, techniques, tools, and documentation aids to support and facilitate the process of design. 9. 2Describe the main phases involved in database design. Database design is made up of two main phases: logical and physical database design.Logical database design is the process of constructing a model of the data used in a company based on a specific data model, but independent of a particular DBMS and other physical considerations. In the logical database design phase we build the logical representation of the database, which includes identification of the important e ntities and relationships, and then translate this representation to a set of tables. The logical data model is a source of information for the physical design phase, providing the physical database designer with a vehicle for making tradeoffs that are very important to the design of an efficient database.Physical database design is the process of producing a description of the implementation of the database on secondary storage; it describes the base tables, file organizations, and indexes used to achieve efficient access to the data, and any associated integrity constraints and security restrictions. In the physical database design phase we decide how the logical design is to be physically implemented in the target relational DBMS. This phase allows the designer to make decisions on how the database is to be implemented. Therefore, physical design is tailored to a specific DBMS. . 3Identify important factors in the success of database design. The following are important factors to the success of database design: †¢Work interactively with the users as much as possible. †¢Follow a structured methodology throughout the data modeling process. †¢Employ a data-driven approach. †¢Incorporate structural and integrity considerations into the data models. †¢Use normalization and transaction validation techniques in the methodology. †¢Use diagrams to represent as much of the data models as possible. †¢Use a database design language (DBDL). Build a data dictionary to supplement the data model diagrams. †¢Be willing to repeat steps. 9. 4Discuss the important role played by users in the process of database design. Users play an essential role in confirming that the logical database design is meeting their requirements. Logical database design is made up of two steps and at the end of each step (Steps 1. 9 and 2. 5) users are required to review the design and provide feedback to the designer. Once the logical database design has been ‘signed off’ by the users the designer can continue to the physical d