10.25 An independent-samples t test, gender, and talkativeness: “Are Women Really More Talkative Than Men?” is the title of an article that appeared in the journal Science. In the article, Mehl et al. (2007) report the results of a study of 396 men and women. Each participant wore a microphone that recorded every word he or she uttered. The researchers counted the number of words uttered by men and women and compared them. The data below are fictional, but they re-create the pattern that Mehl and colleagues observed: Men: 16,345 17,222 15,646 14,889 16,701 Women: 17,345 15,593 16,624 16,696 14,200

a. Conduct all six steps of an independent-samples t test. Be sure to label all six steps.

b. Report the statistics as you would in a journal article.

c. Calculate the 95% confidence interval.

d. Express the confidence interval in writing, according to the format discussed in the chapter.

e. State in your own words what we learn from this confidence interval.

f. Calculate the appropriate measure of effect size. g. Based on Cohen’s conventions, is this a small, medium, or large effect size? h. Why is it useful to have this information in addition to the results of a hypothesis test?