In this study, one exposed group is people who are in the 15-24 age group and had the recent stressor of mental illness. What is the unexposed group for this example? Why is it important to consider both the suicide rate and the relative risk when analyzing a stressor's effect on suicide? In terms of suicide risk, which stressors affect the elderly (65+) more than other age groups? In terms of suicide risk, which stressors affect women more than men?

1) A series of experiments were conducted to determine the effect of air voids on percentage retained strength of asphalt. For purposes of the experiment, air voids are controlled at three levels; low (1-3%), medium (4-6%), and high (7-9%). The data are shown in Table 1. Do the different levels of air voids significantly affect mean retained strength? Use a = 0.05. Table 1: Results of the air voids effect on percentage retained strength of asphalt Air Voids Low Medium High 106 80 78 90 69 80 Retained Strength (%) 103 94 62 90 91 69 79 70 76 88 83 85 92 87 69 95 83 85

Suppose we are interested in comparing the proportion of male students who smoke to the proportion of female students who smoke. We have a random sample of 150 students (60 males and 90 females) that includes two variables: Smoke = "yes" or "no" and Gender = "female (F)" or "male (M)". The two-way table below summarizes the results. Smoke = Yes Smoke = No Sample Size 60 90 Gender = M Gender = F Reference: 3-15-No Tech 9 9 51 81 Describe how to use the data to construct a bootstrap distribution. What value should be recorded for each of the bootstrap samples.

According to the World Health Organization, obesity has reached epidemic proportions globally. While obesity has generally been linked with chronic disease and disability, researchers argue that it may also affect wages. In other words, the body mass index (BMI) of an employee is a predictor for salary. (A person is considered overweight if his/her BMI is at least 25 and obese if BMI exceeds 30.) The accompanying data file includes salary (in $1,000s) for 30 college-educated men with their respective BMI and a dummy variable that represents 1 for a white man and 0 otherwise. Salary BMI White 34 33 1 43 26 1 44 26 1 34 35 0 34 36 1 53 20 1 42 20 0 37 26 1 35 28 1 46 22 1 46 20 1 34 35 0 45 26 1 33 34 0 25 29 0 32 30 1 46 18 0 31 31 0 54 19 1 37 23 0 42 27 1 38 30 1 45 18 0 38 26 0 41 28 1 39 28 1 50 20 1 41 26 1 38 28 1 45 21 1 1. Estimate a model for Salary with BMI and White as the predictor variables. Note: Negative…

A survey of employees at a large financial organisation was conducted to determine the overall sentiment towards various aspects of how the company operates. 30 randomly selected departments in the organisation participated in the study. Every employee in these 30 randomly selected departments filled in a questionnaire, and the data were aggregated to calculate the following two variables of interest: Rating The percentage of favourable responses (in each department) to the overall running of the company. ComplaintsThe percentage of favourable responses (in each department) to how the company handles employee complaints Source: Chatterjee, S. and Price, B. (1977) Regression Analysis by Example. New York: Wiley. (Section 3.7, p.68ff of 2nd ed. (1991).) A simple linear regression was conducted. A scatter plot of Rating versus Complaints is shown in Figure 1 and the results of the regression analysis are shown in Table 1. Rating 80 70 60 50 40 40 Model 1 Figure 1: Rating versus…

15. Commercial real estate prices and rental rates suffered substantial declines in 2008 and 2009 (Newsweek, July 27, 2009). These declines were particularly severe in AsiaB annual lease rates in Tokyo, Hong Kong, and Singapore declined by 40% or more. Even with such large declines, annual lease rates in Asia were still higher than those in many cities in Europe. Annual lease rates for a sample of 30 commercial properties in Hong Kong showed a mean of $1,114 per square meter with a standard deviation of $230.

In a study of how depression may affect one's ability to survive a heart attack, the researchers reported the ages of the two groups they examined. The mean age of 2397 patients without cardiac disease was 69.8 years, while for the 450 patients with cardiac disease, the mean age was 74.0, respectively. Furthermore, 32% of the diseased group were smokers, compared with only 23.7% of those free of heart disease. (1) Determine a 96% confidence interval for the difference in the proportions of smokers in the two groups. (ii) Indicate whether the two groups in the study were different. State the assumptions in order to proceed with the confident interval construction. (ii)

A company has 25 applicants to interview, and wants to invite 7 of them on the first day, 6 of them on the second day, 5 of them on the third day, 4 of them on the fourth day and 3 of them on the fifth day of a week. In how many ways can the applicants be scheduled? Select one: (257,6,5,4,3) None 25! P(25;7)xP(19;6) ×P(14;5)xP(10;4)×P(7;3) C(25;7)xC(19;6)xC(14;5)xC(10;4)xC(7;3)

Read the scenario below to determine which one of the time threats to internal validity (test reactivity, instrumentation, history, and maturation) is of most concern, and provide one way to control for the threat. A researcher examines students' perception of their body image by conducting a 2-year longitudinal study of middle-school students (grades 6 - 8).  Body image is measured using a scale and the same scale is measured under the same conditions at the beginning and end of the study.

Study 2: Pill Appearance and Perceived Pain.    Does the shape or color of a pain pill influence its effectiveness?  Although logically it shouldn’t, whether we believe a drug will work does have a powerful effect on our perceptions (e.g., placebo effect).  In this experiment, 4 groups of adult patients were given the same amount of Advil after dental surgery for pain relief, but the color and shape of the pill varied.  Researchers hypothesized that an unusual shape or color would lead people to believe the pills were new and special and thus would expect them to be more effective than common round, white pills. Researchers also wanted to know if there is an interaction between shape and color Data Labels ShapePill {1=Round; 2=Diamond} ColorPill {1=White; 2=BlueGreen} Gender {0=Woman; 1=Man; 2=Nonbinary person) Descriptions of the Variables and Descriptive Statistics: Referring to the JASP output, and using sentences, present the descriptive statistics of each group: for example:…