Cockroaches tend to rest in groups and prefer dark areas. In a study published in Science Magazine
Question:
Another group consisted of a mixture of real cockroaches and robot cockroaches (4 robots and 12 real cockroaches). The robots did not look like cockroaches but had the odor of male cockroaches, and they were programmed to prefer groups (and brighter shelters). There were 30 trials. In 28 of the trials, all the cockroaches and robots rested under the same shelter, and in 2 of the trials they split up.
Is the inclusion of robots associated with whether they all went under the same shelter? To answer the following questions, assume the cockroaches are a random sample of all cockroaches.
a. Use a chi-square test for homogeneity with a significance level of 0.05 to see whether the presence of robots is associated with whether roaches went into one shelter or two.
b. Repeat the question using Fisher's Exact Test. (If your software will not perform the test for you, search for Fisher's Exact Test on the Internet to do the calculations.) Conduct a two-sided hypothesis test so that the test is consistent with the test in part a.
c. Compare the p-values and conclusions from part a and part b. Which statistical test do you think is the better procedure in this case? Why?
Step by Step Answer:
Introductory Statistics Exploring The World Through Data
ISBN: 9780321978271
2nd Edition
Authors: Robert Gould, Colleen Ryan