11. Van Aken and Asendorpf (1997) studied 139 German 12yearolds.

All of the children completed a general selfworth questionnaire and were interviewed about the supportiveness they experienced from their mothers, fathers, and classmates. The researchers then compared the selfworth of those with high and low levels of support of each type. The researchers reported that “lower general selfworth was found for children with a lowsupportive mother 1t11372 = 4.52, p 6 .001, d = 0.782 and with a lowsupportive father 1t11372 = 4.03, p 6 .001, d = 0.692. . . . A lower general selfworth was also found for children with only low supportive classmates 1t11372 = 2.04, p 6 .05, d = 0.352.”

(a) Explain what these results mean to a person who has never had a course in statistics.

(b) Include a discussion of effect size and power. (When figuring power, you can assume that the two groups in each comparison had about equal sample sizes.)