Question

1. Elephants make low-frequency sounds, inaudible to humans. Apparently these sounds are used in long-distance communication between individuals. You are interested in the response of bull and female elephants to the sound of a female who is ready to mate. You mount a giant speaker on top of your van and drive around the plains looking for elephants. When you find one, you stop 15 m away, play the sound and watch the elephant’s response. You discover: 9 bull elephants approach the van 2 bull elephants do not approach the van 3 female elephants approach the van 11 female elephants do not approach the van Your experiment ends prematurely when one of the bull elephants, apparently enraged by the absence of a female, tips the van over and damages the speaker. You hope that you have enough data to make a claim about males and females.

a. What is the null hypothesis?

b. What statistical test should you use? Choose between the Mann Whitney U Test, Kruskal Wallis Test, sign test, Chi Square test of independence or goodness of fit, or the binomial test.  

c. Calculate your test statistic. Is your result statistically significant? d. What conclusion can you draw from this experiment?

Answer 1