In the preview for this chapter. We discussed the study that analyzed the effect of eye - spot patterns on behavior of moth - eating birds [Seaife, 1976]. The birds were tested in the box with 2 chambers and were free to move from one chamber to another. In one chamber two large eye - spots were painted on one wall. The other chamber had plain wall. The researcher recorded amount of time each bird spent in plain chamber throughout a 60-minute session. Assume the study produced a mean of M = 37 minutes on the plain chamber with SS = 288 for a sample of n = 9 birds. (Note: If the eye spots have no effect, then the birds should spend an average of m = 30 minutes in each chamber.)
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 = 0.05.
b. Calculate the estimated Cohen's d to measure the size of treatment effect.