SPSS Practice Midterm Exam

Your answers to the questions below should be hand-written on the examination page.

"Evidence" and "Support" refer to statistical information that you would select from your SPSS analyses to report in a paper such as means, F ratios, p values. As you would do in a paper, present only relevant information but be sure that your information completely answers the question. [e.g., "see SPSS printout" is insufficient] Your ability determine what is relevant is part of the test!!!

IN ADDITION, please label your SPSS output file surname.spo (e.g., mine would be ruscher.spo), then email it to ruscher@tulane.edu I will use the print-outs to ascertain whether you performed the analysis correctly and, when appropriate, to award partial credit.

Use your homework data set, and give yourself 30 minutes for the exam

Calculators, notes, homework assignments, formula sheets, and the Howell text are legitimate resources for this portion of the exam. SPSS manuals or facsimiles of manual pages are prohibited.

1. The researcher predicts that the effect of time on evaluative ratings of targets is moderated by gender.

a. Using eval1, eval2, and eval3 as the ratings across time and gender, test the researcher's hypothesis and report the relevant results. [I won't say what would be relevant on the actual exam, but you should realize this means the F, df, and p level for the prediction, as well as the corresponding means] 6points

b. Assume that the researcher further wished to examine the simple effect of gender at each level of time. Show these tests. 4 points

2. Another researcher, using the same data set, is interested only the effects of time on evaluation (i.e., she will conduct a 1-way repeated measures ANOVA using eval1, eval2, and eval3). Unfortunately, she is using an old version of SPSS that does not compute epsilon. Using SPSS show the relevant information that she would need to compute it. 4 points

3. A final researcher decides to collapse eval1, eval2, and eval3 into a single index.

a. What is the internal consistency (alpha) for his new measure? 2points

b. If he examines the effect of gender on this index, what is the observed power of the

test? 2 points

c. What sample size would give 80 - 90% power? 4 points

d. What is w² for this effect? 4 points