Researchers often rely on surveys to capture a subjective assessment of well-being. One study finds that holding everything else constant, people seem to be least happy when they are in their 40's. Another study suggests that money does buy happiness, but its effects diminishes as income rises above $75000 a year. The accompanying data file includes survey daa of 100 working adults' self-assessed happiness on a scale of ) to 100, along with their age and annual income. Estimate and interpret a regression model based on Age, Age 2 and income. Predict happiness with income equal = to $80000 and age equal to 30, 45, and 60 Years Predict happiness with Age equal = to 60  and income equal to 25,000, 75000, and 125000

The following graph shows the average grade point average for a particular college from 2004 until 2011. Average GPA 3.20 OA OC OD 3.15 3.10 3.05 3.00 2.95 2.90 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 Year Which one of the following statements is correct? A) Historically, the Average GPA of the college tends to decrease. B) There appears to be no relationship between Year and Average GPA. C) Year is the dependent variable in the graph. D) Average GPA is the dependent variable in the graph.

The number of adult Americans who smoke continues to drop. The table contains estimates of the percentages of adults (ages 1818 and over) who were smokers in the years between 1965 and 201715.and 201715. ???? ?Year � ??????? ?Smokers � 1965 41.94 1970 37.4 1974 37.1 1978 34.1 1980 33.2 1983 32.1 1985 30.1 1987 28.8 1990 25.5 1993 25.0 1995 24.7 1997 24.7 1999 23.5 2001 22.8 2002 22.5 2004 20.9 2006 20.8 2008 20.6 2010 19.3 2012 18.1 2014 16.8 2017 14.0   According to your regression line, how much did smoking decline per year during this period, on the average? Give your answer to three decimal places. average smoking decline:   percentage points

A psychologist believed that as children get older, they engage in more “inactive activities” such as playing computer games, watching TV and surfing the internet. She collected data from 10 children. She recorded the age of each child and the amount of activity (in hours) the child engaged in per week.  Age Activity 7 4.3 9 3.2 10 1 13 1.5 12 1.2 15 0.8 9 3 12 4 15 1.5 14 1.9   Using excel, obtain a scatterplot of the data. Discuss the relationship between age and activity based on the scatterplot. Using excel, obtain the simple linear regression linear regression line predicting activity from age. Interpret the intercept and slope of the regression line. By hand, predict the amount of activity for age = 14. By hand, calculate the residual for age = 14 Using excel output, test the null hypothesis that the slope coefficient is zero using the p-value approach. Write one sentence interpreting the meaning of this result. Make sure to report the test statistic…

Table 9.3 Total cholesterol in 25 patients after taking new statin drug. .. Population mean is 200. Cholesterol levels 219 191 198 214 163 264 248 182 235 209 152 148 145 189 213 230 181 180 100 219 102 249 282 188 264 D. b. Describe the effects of the statin drug on your sample. Do you see any change in the level of cholesterol after taking the drug? c. What is your research question? What are the null and alternative hypotheses? Decide if you want to do a one-tailed or two-tailed test. d. What test? Perform it? What is your critical value? Sketch a normal distribution and draw the critical value or values of z. f. What is your conclusion?

In a data set with 25 scores, if the value 16 occurs 12 times, what is its relative frequency?

Overweight or obese adults from psychiatric programs were recruited and randomly assigned to a treatment group or control group. Patients in the treatment group received both weight-management sessions plus exercise sessions plus their usual care. Patients in the control group received their usual treatment for mental illness and no additional treatment. After 18 months, some of the patients had lost 5% or more of their weight, and some had not. The table summarizes the data. Complete parts (a) and (b) below. Treatment Group Control Group Lost 5% or more 46 29 Did not lose 5% or more 88 106 ..... (a) Find the percentage of each group that lost 5% or more, and compare them descriptively. That is, report both percentages, and indicate what these sample percentages suggest about the effectiveness of the treatment program. Of the treatment group,% of them lost 5% or more. (Round to one decimal place as needed.) Of the control group, % of them lost 5% or more. (Round to one decimal place as…

Melinda thinks that stress might predict lower grades on a statistics final exam. She gives a sample of statistics students a questionaire and then looks for relationships between their answers and their final exam scores. Although she finds no support for her original hypothesis, she does find that the the numbers of hours that students work outside of school is related to exam performance. When she reports the results of her study, she presents them as if the relationship between number of hours worked and exam performance was her original hypothesis. This is a questionable research practice known as: a. open science b. p-hacking c. HARKing d. constraints of generality

kln 2.18 The report "Trends in Education 2010: Community Colleges" (www.collegeboard.com/trends) included the accompanying information on student debt for students graduating with an AA degree from a public community college in 2008. Debt Relative Frequency None 0.62 Less than $10,000 0.23 Between $10,000 and $20,000 0.10 More than $20,000 0.05 a. Use the given information to construct a bar chart. b. Comment on student debt for public community college graduates.

Doctors are testing a new antidepressant. A group of patients, all with similar characteristics, take part in the study. Some of the patients receive the new drug, while others receive the traditional drug. The data are shown in the contingency table below. What is the relative risk of insomnia for those who receive the new drug? Round to two decimal places. Insomnia New drug- 52. No insomnia-226—total=278 Traditional drug-36. 295—331(total) Total- 88. 521. ( no insomnia)—— total-609