Question: In the Preview for this chapter, we discussed a study that examined the effect of eye-spot patterns on the behavior of moth-eating birds. The birds were tested in a box with tow chambers and were free to move from one chamber to another. In one chamber, two large eye-spots were painted on the wall. The researcher recorded the amount of time each bird spent in the plain chamber during a 60-miniute session. Suppose the study produced a mean of M = 37 minutes on the plain chamber with SS = 288 for a sample of n = 9 birds.

a. Is this sample sufficient to conclude that the eye-spots have a significant influence on the birds’ behavior? Use a two-tailed test with a = .05.

b. Compute the estimated Cohen’s d to measure the size of the treatment effect.