STAT 516 - Spring 2003 - Homework 4
Due: Friday, March 7th
1) (4 points) Pg. 279: 1, 2, 12 (make sure to answer all six parts to 12)
2) (6 points) The simulated data set on the web is based on an experiment reported in the Journal of
Nonverbal Behavior (Fall 1996). A sample of 36 introductory psychology students was randomly
divided into six groups. Each was asked to view one of six slides showing a person making either an
angry, disgusted, fearful, happy, sad, or neutral face. After viewing the slides the students rated the
degree of dominance they inferred from the facial expression (a higher score indicating more
dominance).
a) Write down the equation of the one-way ANOVA model that is described by this set-up. Be sure to
clearly identify each parameter and the sample sizes.
b) Check that the assumptions for performing a one-way ANOVA hold, including using Levene's test.
c) What hypothesis is being tested by the F-statistic in the ANOVA table? State your conclusion at the
α=0.05 level.
d) Use the Holm procedure with an experiment-wise (family-wise) αΤ=0.05 level to test all of the pair-
wise differences, and make a display showing the ranking in which the different facial expressions
reflect dominance.
e) Use a contrast to make a 95% confidence interval for the difference in dominance between the average
of the two strong negative emotions (Angry and Disgusted) and the positive emotion (Happy).