Overview
PSYCHOLOGY 320L
Problem Set #5: Within-Subjects and Mixed ANOVA Name: Score: 1. A Stanford University study (Carlsmith, 1981) suggests running aids romance. Below are the ratings five couples give to their romantic life after differing amounts of jogging per week for a month; higher ratings indicate the couples are happier romantically. Miles Run by the Couples: 0 1 2 3 4 3 5 6 4 3 4 5 8 4 3 4 7 7 6 1 2 6 10 5 2 2 6 9 6 1 A. State what the independent variable is and what the dependent variable is. B. State the null hypothesis and the alternative hypothesis. C. Calculate the degrees of freedom and state the decision rule for = .05. D. Calculate the F ratio (by hand and by computer). E. State your decision and write your conclusion. F. Conduct a planned comparison to determine whether couples are significantly happier when they don't run at all than when they run 4 miles a week using = .05. Be sure to state your hypotheses, state the decision rule, calculate the F ratio for the comparison, state the decision, and write your conclusion. G. Conduct a planned comparison to determine whether couples are significantly happier when they run 2 miles a week than when they run 0, 1, 3, or 4 miles a week using = .05. Be sure to state your hypotheses, state the decision rule, calculate the F ratio for the comparison, state the decision, and write your conclusion. SPSS Information Descriptive Statistics Group n Mean Standard Deviation Test of Within-Subject Effects (look at first row of each section only) Source SS df MS F Significance Eta- squared Observed Power
2. Imagine an experiment in which subjects are divided into two groups: one group receives easy questions (a1) and another group receives difficult questions (a2). All subjects are asked to answer some questions with 1 distractor (b1), 2 distractors (b2), and 3 distractors (b3). The time subjects took to correctly answer a question was measured (in seconds). The data are as follows: Number of Distractors Type of Question One Distractor (b1) Two Distractors (b2) Three Distractors (b3) Easy Questions (a1) 3 5 4 4 4 2 2 3 3 4 6 4 2 5 5 4 2 6 2 4 4 3 3 5 6 2 2 4 6 3 Difficult Questions (a2) 5 9 5 4 5 8 4 3 9 5 7 10 6 3 10 3 8 6 8 5 7 2 8 8 3 6 9 3 8 6 A. What are the independent variables and the dependent variable? B. State the hypotheses for the three tests. C. Calculate the degrees of freedom for the three analyses and state the three decision rules for =.05. D. Calculate the three F ratios (by hand and by computer). E. State your decisions and write your conclusions for each test. F. What would be the appropriate next step, based on the results you found?
2. SPSS Results Descriptive Statistics IV1 IV2 Mean s n Test of Within-Subject Effects (look at first row of each section only) Source SS df MS F Significance Eta- squared Observed Power Test of Homogeneity of Variance Levene Statistic df1 df2 Significance Test of Between-Subjects Effects Source Sum of Squares df Mean Squares F Sig. Eta- squared Observed