Robots trained to behave like ants. Refer to the Nature

(Aug. 2000) study of robots trained to behave like ants, presented in Exercise 10.35 (p. 553). Multiple comparisons of mean energy expended for the four colony sizes were LO4 conducted with an experimentwise error rate of .05. The results are summarized as follows:

Sample mean: .97 .95 .93 .80 Group size: 3 6 9 12

a. How many pairwise comparisons are conducted in this analysis?

b. Interpret the results shown.