Quick Answers to Problems

1.    The national unemployment rate in a recent month was 4.9 percent. You think the rate may be different in your city, so you plan a sample survey that will ask the same questions as the Current Population Survey.  Consider p as the local employment rate. Identify the null and the alternative hypotheses that you will test to see if the local rate differs significantly from 4.9 percent.

2.       The financial aid office of a university asks a sample of students about their employment and earnings. The report says, “For academic year earnings, a significant difference (P = 0.028) was found between the sexes, with men earning more on the average.”

True or false: The report shows that the difference in earnings in the sample was large enough that it would rarely occur in more than 3 percent of samples drawn from a population in which men's and women's average earnings are equal.