Chapter 8.1, Problem 16P

Marketing: Shopping Time How much customers buy is a direct result of how much time they spend in a store. A study of average shopping times in a large national housewares store gave the following information (Source: Why We Buy: The Science of Shopping by P. Underhill):

Women with female companion: 8.3 min.

Women with male companion: 4.5 min.

Suppose you want to set up a statistical test to challenge the claim that a woman with a female friend spends an average of 8.3 minutes shopping in such a store.

1. (a) What would you use for the null and alternate hypotheses if you believe the average shopping time is less than 8.3 minutes? Is this a right-tailed, left-tailed, or two-tailed test?
2. (b) What would you use for the null and alternate hypotheses if you believe the average shopping time is different from 8.3 minutes? Is this a right-tailed, left-tailed, or two-tailed test? Stores that sell mainly to women should figure out a way to engage the interest of men—perhaps comfortable seats and a big TV with sports programs! Suppose such an entertainment center was installed and you now wish to challenge the claim that a woman with a male friend spends only 4.5 minutes shopping in a housewares store.
3. (c) What would you use for the null and alternate hypotheses if you believe the average shopping time is more than 4.5 minutes? Is this a right-tailed, left-tailed, or two-tailed test?
4. (d) What would you use for the null and alternate hypotheses if you believe the average shopping time is different from 4.5 minutes? Is this a right-tailed, left-tailed, or two-tailed test?