508 Chapter 14 Repeated-Measures Designs
Addition Subtraction MultiplicationNon-calculator owners 10 7 6
76 5
65 5
97 8
96 9
a. Run the analysis of variance.
b. Do the data suggest that I should have given in and bought my daughter a calculator? (I did
anyway. She is now in her late 30s and is a fully certified actuary—so what do I know?)
14.7 For the data in Exercise 14.6,
a. Calculate the variance–covariance matrices.
b. Calculate using your answers to part (a).
14.8 From the results in Exercise 14.7, do we appear to have reason to believe that we have met
the assumptions required for the analysis of repeated measures?
14.9 For the data in Exercise 14.6,
a. Calculate all possible simple effects after first plotting the results.
b. Test the simple effects, calculating test terms and adjusted degrees of freedom where
necessary.
14.10 In a study of the way children and adults summarize stories, we selected 10 fifth graders
and 10 adults. These were further subdivided into equal groups of good and poor readers
(on the hypothesis that good and poor readers may store or retrieve story information differ-
ently). All subjects read 10 short stories and were asked to summarize the story in their own
words immediately after reading it. All summaries were content analyzed, and the numbers
of statements related to Settings, Goals, and inferred Dispositions were recorded. The data
are collapsed across the 10 stories:
Age
Adults Children
Items Setting Goal Disp. Setting Goal Disp.
Good readers 876 552
564 784
555 774
786 643
644 442
Poor readers 763 222
531 201
662 541
441 442
553 220
Run the appropriate analysis.
14.11 Refer to Exercise 14.10.
a. Calculate the simple effect of reading ability for children.
b. Calculate the simple effect of items for adult good readers.
14.12 Calculate the within-groups covariance matrices for the data in Exercise 14.10.
14.13Suppose we had instructed our subjects to limit their summaries to 10 words. What effect
might that have on the data in Exercise 14.10?
14.14 In an investigation of cigarette smoking, an experimenter decided to compare three different
procedures for quitting smoking (tapering off, immediate stopping, and aversion therapy).
She took five subjects in each group and asked them to rate (on a 10-point scale) their
desire to smoke “right now” in two different environments (home versus work) both before
and after quitting. Thus, we have one between-subjects variable (Treatment group) and two
within-subjects variables (Environment and Pre/Post).gN