Analysis of Variance (ANOVA) - Definition

Analysis of Variance (ANOVA) - Definition Analysis of Variance, or ANOVA for short, is a statistical test that looks for significant differences between means on a particular measure. For example, say you are interested in studying the education level of athletes in a community, so you survey people on various teams. You start to wonder, however, if the education level is different among the different teams. You could use an ANOVA to determine if the mean education level is different among the softball team versus the rugby team versus the Ultimate Frisbee team. Key Takeaways: Analysis of Variance (ANOVA) Researchers conduct an ANOVA when they are interested in determining whether two groups differ significantly on a particular measure or test.There are four basic types of ANOVA models: one-way between groups, one-way repeated measures, two-way between groups, and two-way repeated measures.Statistical software programs can be used to make conducting an ANOVA easier and more efficient. ANOVA Models There are four types of basic ANOVA models (although it is also possible to conduct more complex ANOVA tests as well). Following are descriptions and examples of each. One-way between groups ANOVA A one-way between groups ANOVA is used when you want to test the difference between two or more groups. The example above, of education level among different sports teams, would be an example of this type of model. It is called a one-way ANOVA because there is only one variable (type of sport played) that is being used to divide participants into different groups. One-way repeated measures ANOVA If you are interested in assessing a single group at more than one time point, you should use a one-way repeated measures ANOVA. For example, if you wanted to test students’ understanding of a subject, you could administer the same test at the beginning of the course, in the middle of the course, and at the end of the course. Conducting a one-way repeated measures ANOVA would allow you to find out whether the students’ test scores changed significantly from the beginning to the end of the course. Two-way between groups ANOVA Imagine now that you have two different ways in which you want to group your participants (or, in statistical terms, you have two different independent variables). For example, imagine you were interested in testing whether test scores differed between student athletes and non-athletes, as well as for freshmen versus seniors. In this case, you would conduct a two-way between groups ANOVA. You would have three effects from this ANOVA- two main effects and an interaction effect. The main effects are the effect of being an athlete and the effect of class year. The interaction effect looks at the impact of both being an athlete and class year. Each of the main effects is a one-way test. The interaction effect is simply asking if the two main effects impact each other: for example, if student athletes scored differently than non-athletes did, but this was only the case when studying freshmen, there would be an interaction between class year and being an athlete. Two-way repeated measures ANOVA If you want to look at how different groups change across time, you can use a two-way repeated measures ANOVA. Imagine you’re interested in looking at how test scores change across time (as in the example above for a one-way repeated measures ANOVA). However, this time you’re also interested in assessing gender as well. For example, do males and females improve their test scores at the same rate, or is there a gender difference? A two-way repeated measures ANOVA can be used to answer these types of questions. Assumptions of ANOVA The following assumptions exist when you perform an analysis of variance: The expected values of the errors are zero.The variances of all errors are equal to each other.The errors are independent from one another.The errors are normally distributed. How an ANOVA is Done The mean is calculated for each of your groups. Using the example of education and sports teams from the introduction in the first paragraph above, the mean education level is calculated for each sports team.The overall mean is then calculated for all of the groups combined.Within each group, the total deviation of each individual’s score from the group mean is calculated. This tells us whether the individuals in the group tend to have similar scores or whether there is a lot of variability between different people in the same group. Statisticians call this within group variation.Next, how much each group mean deviates from the overall mean is calculated. This is called between group variation.Finally, an F statistic is calculated, which is the ratio of between group variation to the within group variation. If there is significantly greater between group variation than within group variation (in other words, when the F statistic is larger), then it is likely that the difference between the groups is statistically significant. Statistical software can be used to calculate the F statistic and determine whether it is significant or not. All types of ANOVA follow the basic principles outlined above. However, as the number of groups and the interaction effects increase, the sources of variation will become more complex. Performing an ANOVA Because conducting an ANOVA by hand is a time-consuming process, most researchers use statistical software programs when they are interested in conducting an ANOVA. SPSS can be used to conduct ANOVAs, as can R, a free software program. In Excel, you can do an ANOVA by using the Data Analysis Add-on. SAS, STATA, Minitab, and other  statistical software programs  that are equipped for handling bigger and more complex data sets can also be used to perform an ANOVA. References Monash University. Analysis of Variance (ANOVA). csse.monash.edu.au/~smarkham/resources/anova.htm

The Weight Of Real Wrestlers Essays - Sports Rules And Regulations

The Weight Of Real Wrestlers Essays - Sports Rules And Regulations The Weight Of Real Wrestlers High School Wrestling has always been thought of as the hardest and most enduring sport that takes place in high school. Only the toughest Jocks try out, and the weak are quickly discarded. Young women showing school spirit come to watch as the arms of young men in spandex are mingled about. During matches, coaches yell and scream at their young apprentices while they desperately battle to pin their opponent of equal weight. But, how equally are the two enemies matched? How much weight did one person have to lose, and how fast did he have to do it to be able to wrestle in that weight class? Once the wrestler makes his weight does he really have any physical energy left to wrestle? Losing an extraordinary amount of weight in a short amount of time is dangerous and unhealthy, and should be regulated for the safety of the athletes. Coach James Derek Donoho is now in his third year of being head coach at Don Lugo High School. He says wrestling is a very dangerous contact sport that always has the risk of injuries, and people get hurt everyday. He believes it's a good experience for young men and he is glad he went through it when he was in high school. Physical injuries come with the turf, and every person knows it when they join wrestling or any other sport. It's the un-implied risks that are not seen until commitments are made, that are the most dangerous to young athletes. Donoho is pro losing weight and says its good to loose weight and move to a lighter weight class, because it's a little easier on the wrestler. It feels to them that they are wrestling someone lighter then they are. That is a tactical advantage, however people also move up to wrestle in higher weight levels to fill spots. That makes it unnecessary for teens to lose weight because they are already wrestling someone lighter then they are. We don't pressure our players to lose a lot of weight, says Donoho, they chose which weight class they want to wrestle in. If that's true, then there are a lot of young athletes who are willing to lose a tremendous amount of weight in a short amount of time just to make Varsity. Do people really put themselves in such danger to achieve the pride of being on a varsity team? Brandon Frescas, a third year wrestler on the team, says coaches just flat out ask us if we could get down to a certain weight by a certain time to fill spots. Sometimes it's moving up a weight class, sometimes it's losing a little weight, and sometimes it's a lot of weight. Losing 10 to 15 pounds in a week is a lot of weight to lose. 10 to 15 pounds in a week is an absurd amount of weight to lose. On T.V advertisements say their diet can help people lose 10 to 15 pounds in a month, but never does it say one week. 15 pounds is about the size of a medium dog. Could anyone imagine stuff about the size of a dog leaving ones body in only one week? Michael Nava, also a third year wrestler, says coach asked me what weight I thought I could get down to, and I told him 135 pounds. I weighed about 137 pounds and he asked me if he could count on me to get down to 130 pounds. I thought about it and told him yes because I didn't want to let him down. Pressure from the coaches exists and every pl ayer knows its there. Although the coaches won't admit it, Michael Nava says, it's dangerous if you have to lose a lot of weight. Losing an enormous amount of weight such as 10 to 15 pounds in one week seems impossible to an everyday person. But, according to the wrestlers it's only almost impossible. There is an entire process wrestlers go through and it's different depending upon how much weight needs to be lost. The secrets are passed down and taught to the younger wrestlers by the more experienced ones. The first thing taught is

Affects of the Cold War on the Middle East Essay - 1

Affects of the Cold War on the Middle East - Essay Example The effects of the Cold War on the socio-political affairs in the Middle East were very diverse and discursive in nature due to a number of economic, historical, political and religious causes such the Arab-Israel antagonism, the overt anti-religious nature of Communism, the vast reserve of furnace oil in the Middle Eastern countries, the non-democratic and most likely monarchic political systems in those countries during the Cold War and Islam as the religion of the majority of the people in the Middle East. Since most of the political governments of the Middle East were non-democratic and, to a great extent, monarchic after the Second World War up to 2000, the then rulers were forced to take shelter either in the US block or the Soviet in order to survive in the countries’ power with the support of any of the two superpowers. Also due to the vast reserve of oil, the Middle Eastern countries were strategically important for both of the superpowers. Therefore, the rulers of th ese countries needed backings of any of these two superpowers against the expansionist invasions of the others. Before the Soviet invasion in Afghanistan, the Arab countries were more or less neutral, though because of being geographically close to the Soviet Union and the overt US support for Israel in this region, the countries were more influenced by the Soviet Leaders. Because of the Soviet invasion in Afghanistan, the countries were alarmed; they began to feel the threat from the Soviet Union’s aggressive nature.

An Analysis of Advertising Assignment Example | Topics and Well Written Essays - 1500 words

An Analysis of Advertising - Assignment Example What is more, in accordance with Steinbeck, material well-being and financial security are among the most things for Americans, on which they depend a lot even though they regard themselves as independent, self-sufficient and self-reliant. Furthermore, among the characteristic features of Americans is the inconsistency of their behavior and their tendency to â€Å"function by paradox†, which means that they themselves cancel their rules and habits by introducing new ones (Steinbeck). Finally, Americans live in accordance with the American Way of Life despite the fact that nobody can give a clear definition of what constitutes it and what it means. In this very paper, the way the commercials reflect the traits of Americans will be analyzed. More specifically, the correctness and usefulness of illustration in understanding the characteristics of Americans will be touched upon. For this purpose, five particular traits have been chosen from the article by John Steinbeck. Among them are the following ones: Americans’ tendency to act excessively (â€Å"for the most part we are an intemperate people†), being dependent on money (â€Å"we are complacent in our possessions, in our houses, in our education; but it is hard to find a man or woman who does not want something better for the next generation†), being good to unknown people (â€Å"Americans are remarkably kind and hospitable and open with both guests and strangers†), having a belief in self-sufficiency (â€Å"we believe [†¦] that we have inherited self-sufficiency and the ability to take care ourselves†), and being charitable in case the re is spare money (â€Å"if we have enough gold – we contribute it back to the nation in the form of foundations and charities† (Steinbeck). For this purpose, five commercials have been chosen: Audi commercial, a commercial that presents new contract option from T-Mobile,

An Analysis of Dear Mama by Tupac Shakur Research Paper

An Analysis of Dear Mama by Tupac Shakur - Research Paper Example Many movements like the Black Panthers Party had recognized the rise of racism in American society during the seventies but could not do much during the eighties when it was finally dissolved. Afeni Shakur was a part of this party. People who were born into the eighties were thus born into an environment of hatred that Tupac speaks of in his song when he says,Though back at the time, I never thought I'd see her face Ain't a woman alive that could take my mama's place Suspended from school; and scared to go home, I was a fool with the big boys, breaking all the rules I shed tears with my baby sister (Shakur). In these lyrics, there is an understanding of the fact that the poverty and hardships that were faced were not a reflection merely of class but also of race. An understanding of the hardships that were faced by African Americans in the eighties is clearly outlined in these lines when one takes the context of the song into account. A historical analysis of the song would thus, lead one to believe in the importance of the song that speaks of the poverty that people of a certain race had to suffer and the hardships that they had to undergo as a result of the discrimination that they had to face. The analysis of history would lead one to believe that the destructive potential that racism had in the United States of America was channelized into creating the songs that Tupac did. His songs were an exposition of the racist mentalities that were prevalent in the minds of people in the eighties. Tupac is aware of his personal position within the historical times that he was a part of. The pe rsonal dedication of the song to his mother is a proof of the fact that the song owes its existence to the personal experiences that Tupac went through as a child. The song incorporates the problems that the poverty of the African Americans could lead them to. Poverty in many cases also coincided with the use of drugs and other substances that were banned. Afeni Shakur was addicted to crack and this is referred to in Tupac’s song. When he says that despite the fact that his mother was a â€Å"crack fiend†, she â€Å"always was a black queen† (Shakur), he means to understand the troubles that she went through and also the paths that she took to avoid those troubles. The anger that Tupac feels towards the society for making him and his mother face hardships because of their skin color comes through in Dear Mama. The importance of this lies in the fact that current policy decisions may be able to gain from rap music like the one that Tupac produced. Writers like Ro nald J. Stephens and Earl Wright II talk of the possibility of using songs such as Dear Mama as a â€Å"qualitative data source† (Stephens and Wright). The personal experiences of Tupac find mention in Dear Mama and these can be used to analyze the conditions that have shaped race relations in the America of today. The song also reveals the conditions of struggle that were to be endured by black women in urban areas of America during the eighties. In this song, Tupac talks about the problems that had to be faced by his mother as representative of the problems.

Causes and effects of fluctuation in oil price

Causes and effects of fluctuation in oil price This report discusses about the most essential energy resource and the core in economics that is oil. Since it is now used in a variety of ways to operate any machines for everyday life especially automobiles, its needs and wants has been grown rapidly. However, such unsustainable and finite amount of oil now does tremendous matters to global economics. When it was not fully used for running machines, people in history used for constructions and medicines. However, with its discovery of many usable ways such as lighting, the wants of oil has been rocketed. After many years have been used oil for running machines and other fields, economists found that oil price is actually affected by some crucial reasons and events occurred. Following this, it explains with examples about how such natural disasters, wars, recession, and oil crisis can cause the oil price changed. Also, it talks about effects as what would happen to politics and economics after the fluctuation in oil price. Since the re is high in demand of oil and limited supply, the price of oil is very high. Also, environmentalists claim that even it has replaced coal successfully in running machines and automobiles, it still emissions harmful pollutant to nature. Therefore, many researchers have been made a research for an alternative energy source to oil. Actually, there are many renewable energy sources found to use as alternative energy to oil after it is depleted, but it still has to study more on it due to new technology required to be usable. Hence, there are many arguments about whether we should keep oil as main energy source or change it to new energy source to lessen the current oil price and care about remaining amount of crude oil even it costs a lot. We infer that the oil price fluctuation can make significant changes economically, socially, and politically. We also think that searching for alternative energy sources can help the environment and maintain more stable economy. 1.0 Introduction The oil, which is used for everyday life, is just as important as water and air. Oil is used not only for running automobiles and producing electricity but also producing plastics, clothes, and electrical goods as well. Thus, we could say oil is a fundamental material to produce goods we need in everyday life. This research paper will mainly discuss oil and recognize how the money in exchange for oil, in other words, the oil money affects global economy. Also, we will see how other economists think about viable alternatives to oil in future. 2.0 History of Oil use Oil has been known as one of the most significant and essential energy sources used and progressed for numerous purposes since thousands of years. Despite modern major oil use is to run automobiles such as cars, buses, trucks, and ships, ancient people used in many other ways. According to history, ancient people used pure oil not only as a material for binding materials and as a sealant for waterproofing various surfaces but also as worked materials to pave asphalt on walls and roads. With its numerous effects has brought economic growth, the world started to recognize the importance of oil use. It was also discovered that the Chinese were the first knew the importance use of oil and to discover underground oil and drew from the wells in order to use for lighting around 500 B.C. Ever since that time many countries has begun to find oil wells around the world due to the important roles for the use of oil (BERA The Oil Gas Industry). Moreover, oil development has been quite active s ince long time ago. For example, Poland was the first country in the world trade the oil that was in 1853, and then comes Romania in 1857. In North America, the first commercial was in 1858. In 1959 Titusville was very famous for its oil well production of twenty five barrels a day. The U.S started to produce millions and millions of barrels during the past 50 years after the first production. For example; 2000 barrels in 1859 after 40 years 57 million barrels were produced in a year and still increasing until now. (Wilson, 2010) 3.0 Causes of fluctuation in oil price Knowing the reasons for oil price fluctuation is very important; since knowing such information can help the investor to invest at the right without any risk. It is very perplexing to know the exact cause of fluctuation in oil price; however, we will highlight the main causes and effects of phenomenon. 3.1.0 Causes There are four main causes change oil price; hurricane Katrina, middle-east wars, recessions, and oil crisis in the 1970s. 3.1.1 Hurricane Katrina Hurricane Katrina in 2005 caused the oil production in the Southern Gulf Coast in the U.S to stop completely, and due to the demand and to the lag of oil production; the price of oil barrels increased suddenly to $70 per a barrel. The prices declined when the U.S government decided to release 30 million oil barrels from the Strategic Petroleum Reserve (SPR) (Editorial Dept, 2009). 3.1.2 Middle East wars The wars happened in the Middle East between Iraq and Afghanistan in July, 2008 caused the prices of oil to increase to more than $136 per barrel. The Middle East is known that it is one of the richest regions of oil. Therefore, due to the high prices of oil at that time, the demand for oil dramatically decreased; people started to demand less and save money. Due to this low demand, the prices of oil started to return back to normal (Editorial Dept, 2009). 3.1.3 Recession Recession caused the oil prices to change in two ways. First, the recession caused the employees to work lesser, and some even started to work from their homes; therefore, they are not demanding often for oil (e.g. transportation). Hence, the prices of oil decreased due to the low demand. Secondly, the demand for other products (e.g. electronics) decreased due to recession. The manufacturing countries which supply these products started to supply less since they started to lose proifit, so less shipment of products occurred less use of oil and this caused the prices of oil to decline (Editorial Dept, 2009). 3.1.4 Oil crisis in the 1970s The prices of oil in the Middle East were low, most of the developed countries such as the U.S decided to rely more on importing the oil. The Organization of Petroleum Exporting Countries (OPEC) decided to limit their production of oil in order to make the higher oil price (Wright Boorsw, 2011). 3.2.0 Effects There are two effects showing what would be likely results of politics and economics after the changes in oil price. 3.2.1 Political effects Because of the negative effects of oil price fluctuation in the United States, the citizens decided to vote for Barack Obama in the 2008 elections. (Crenshaw, Maniam Subramaniam, 2010). 3.2.2 Economical effects There is a relationship between oil price fluctuating and income rate. For example, when the price oil increase, the income rate of the labors decrease in order for the industry to make up for the loss and make profit. Also, when the prices of oil increased, some storeowners couldnt pay for the gas deliveries and they had to shut down their businesses. Not to mention the increase of shipping fees, transportation, and food prices (Crenshaw, Maniam, Subramaniam, 2010). 4.0 Alternative energy sources to Fossil Fuels Countries around the world are reconsidering other energy sources to oil due to its increasing prices, polluting waste and the remaining amount left of it. Oil is formed over millions of years from the remains of animals and plants, covered with a layer of sand and silt. Crude oil and petroleum are also known as rock oil, developed by heat and pressure on the layers. Today oil is used to fuel vehicles, heat houses, and make numerous products ranging from medicines to plastics. However, a great pitfall of oil is the emission of harmful gases when burnt. Before the age of oil, coal was the dominating fuel, as stated by BBC (Alternatives to oil, 2000).Not only was it a reliable provider of electricity, it [was] also an essential fuel for steel and cement production, and other industrial activities (World Coal Association, N.D). However, it lost its popularity due to the fact that a large amount of poisonous gases, like carbon dioxide and sulphur dioxide are produced in its burning process, contributing negatively to the change in climate. Moreover, nuclear power is said to be friendly regarding the global warming. For example, the United Arab Emirates has been depending on oil for a very long period as a main income generator. However, the emirates are trying their best to stimulate other inflows from tourism, manufacturing and plans for research and development of new energy programs since they know that oil would eventually run out one day. According to the Emirates Nuclear Energy Corporation (ENEC), the development of nuclear power plants in Abu Dhabi will help serving the growth in energy needs in the future. On the other hand, some countries fear to take the risk of having nuclear plants because of the rising rate of tragic accidents. The recent leakage of nuclear and radioactive substances in Japan, due to the 8.9 Richter scale earthquakes, is an example. Technology innovations are creating a path to the usage of new, more environmentally sociable fossil fuels. Renewable fuels include hydro-electric energy, solar energy, biomass energy, wind energy and hydrogen. Renewable fuels promote countries to use nature and a high technological plan to produce power. In Norway for instance, hydro-electric power is used to the fullest as reported by BBC (Alternatives to oil, 2000). Wind and wave power are another promising fuels. Solar power is coming on by leaps and bounds. There are already photo-voltaic cells which will provide power on a cloudy à ¢Ã¢â€š ¬Ã‚ ¦ winters day, or even by moonlight (Alternatives to oil, 2000). However, the hesitation and reluctance of countries to use such power sources falls under the aspect of price. A lot of money will be required to build wind turbine, solar panels, and hydrogen in conversion of technologies. All in all, there is a wide variety of alternatives to oil, however the users should evaluate the benefits and drawbacks for each power source and the effects generated to the society from the global view. 5.0 Conclusion To sum up, our world consists of variety of sources. Oil is one of the most important sources that are used in todays life, yet it is a non-renewable source. Therefore, looking for alternatives for oil can help stabilize economy and environment. Furthermore, due to some environmental and humanistic behaviors, oil prices began to increase and decline; this affected the world in many ways economically, politically, and socially.

David Burns Feeling Good: Depression :: essays research papers

David Burn's Feeling Good: Depression In the book Feeling Good , David Burns, MD, the author, outlines certain cognitive techniques an individual suffering from depression could use in combating the disorder. He begins the book by briefly describing the pertinence and the prevalence of depression. The author captures the audience's attention in the first paragraph: " In fact depression is so widespread it is considered the common cold of psychiatric disturbances" (Burns, 1992) p. 9. Burns(1992), continues to suggest that the difference between the common cold and depression lies in the fact that depression is lethal. Irwing and Barbara Serason (1996) suggest that at least 90 percent of all suicide victims suffer from a diagnosable psychiatric disorder at the time of their death. Irwing and Barbara Serason (1996) also state that one of the risk factors in committing suicide is the presence of mood disorder. Silverman (1993) states that suicide among young people 15 to 19 years of age has increased by 30 percent from the years 1980 to 1990. In my opinion David Burns brings up a valid issue in addressing the pertinence of depression as it pertains to peoples tendencies of committing a suicide; other academics have agreed with the same findings. However these academics have not specifically stated that depression is the only risk factor of committing a suicide. They did not even suggest that depression is the heighest weighted risk factor in committing a suicide. The impression the reader gets after reading the introductory paragraph of the Feeling Good book is that severe depression will inevitably result in suicide unless it is cured. Implying that if a person has a depressive disorder, it will lead to a suicide can be dangerous and counterproductive for a person who already feels hopeless; this may reaffirm their belief of hopelessness and the inevitability of the disorder. Once the first paragraph is passed the author indicates that there is hope in curing depression, giving the reader an encouragement to continue with the book. According to the Diagnostic and Statistical Manual of Mental Disorders(DSM-IV), mood disorders are classified into two broad categories, bipolar and unipolar depressive disorders. The book Feeling Good only talks about the unipolar depressive disorders, thus, I will only concentrate on that one category. Unipolar mood disorders are classified under axis I of the DSM-IV. Unipolar depressive disorders are further classified into two categories: dysthymic, and major depressive disorder. Even though both of the disorders are mood disorders they have some fundamental differences and similarities. According to DSM-IV people experiencing major depression must have depressed moods and/or diminished interest for at least two weeks, for most of the day,