This preview shows page 1. Sign up to view the full content.
Unformatted text preview: only. We never prove H0 true, we can only state whether we have enough evidence to reject H0 (which is evidence in favor of Ha, but not proof that Ha is true) or that we don’t have enough evidence to reject H0. 6 Example (Exercise 6.37, p. 418): Each of the following situations requires a significance test about a population mean . State the appropriate null hypothesis H0 and alternative hypothesis Ha in each case: a. Census Bureau data shows that the mean household income in the area served by a shopping mall is $72,500 per year. A market research firm questions shoppers at the mall to find out whether the mean household income of mall shoppers is higher than that of the general population. b. Last year, your company’s service technicians took an average of 1.8 hours to respond to trouble calls from business customers who had purchased service contracts. Do this year’s data show a different average response time? STEP 2: Calculate the value of the test statistic. A test statistic measures compatibility betw...
View Full Document
- Spring '08