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STAT 3504 Assignment 1 DUE: Monday, January 18 For each of the problems #1 through #3, answer the following questions: a) b) c) d) e) What is the response variable? Identify all factors, factor levels, factor level combinations. What are the treatments? What is the study unit? Is the study experimental, observational or mixed? Why? 1. A magazine publisher wants to compare 3 different styles of covers for magazine that will be offered for saleat supermarket checkout lines. She assigns 60 stores at random to the 3 styles of covers and records the number of magazines that are sold in a one-week period. 2. In a study to determine how 5 bookstores in the same city differ with respect to the age of their customers, a market researcher asks 50 customers of each store to give their age. 3. A medical investigator studied the relationship between the response to 3 blood pressure lowering drug types for hypertensive males and females. The investigator selected 30 adult males and 30 adult females and randomly assigned 10 males and 10 females to each of the 3 drug types. 4. #16.2 in text 5. #16.6 in text 6. In a study to determine whether students in B.A., B.Sc, and B.B.A. programs earn different amounts in summer jobs, a random sample of 5 students from each of these programs was asked to report what they earned the previous summer. The results ($1000) are given below. Assume the fixed effects, single factor ANOVA model Y ij = i + ij is appropriate. DO BY HAND. unit j factor level i 1 2 3 4 5 B.A. 3.3 2.5 4.6 5.4 3.9 B.Sc. 3.9 5.1 3.9 6.2 4.8 B.B.A. 4.0 6.2 6.3 5.9 6.4 a) b) c) d) e) 7. Prepare aligned dot plots of the data. Do the factor level means appear to differ? Does the variability of the observations within each factor level appear to be approximately the same for all factor levels? Obtain the fitted values. Obtain the residuals. Plot the residuals against the fitted values. Assume for now that there are no really serious assumption violations. Conduct a test of hypothesis to determine whether or not the average summer earnings for the three degree types differ. Use = .05. Be sure to state the null and alternative hypotheses, the test statistic, the rejection rule and the conclusion in a sentence using the words of the problem. Use SAS to check your ANOVA table results from part (e). Data is to be put in from the keyboard. Hand in a copy of both the program and the output. Remember to put a FOOTNOTE statement with you name and student number at the beginning of your program.