Suppose, as in Exercise 4.37, that we wish to compare methods of influencing voters to support a particular candidate, but in this case we are specifically interested in testing whether a phone call is more effective than a flyer. Suppose also that our random sample consists of only 200 voters, with 100 chosen at random to get the flyer and the rest getting a phone call.

(a) State the null and alternative hypotheses in this situation.

(b) Display in a two-way table possible sample results that would offer clear evidence that the phone call is more effective.

(c) Display in a two-way table possible sample results that offer no evidence at all that the phone call is more effective.

(d) Display in a two-way table possible sample results for which the outcome is not clear: There is some evidence in the sample that the phone call is more effective but it is possibly only due to random chance and likely not strong enough to generalize to the population.

Exercise 4.37

When getting voters to support a candidate in an election, is there a difference between a recorded phone call from the candidate or a flyer about the candidate sent through the mail? A sample of 500 voters is randomly divided into two groups of 250 each, with one group getting the phone call and one group getting the flyer. The voters are then contacted to see if they plan to vote for the candidate in question. We wish to see if there is evidence that the proportions of support are different between the two methods of campaigning.