When you reject a true claim with a level of significance that is virtually zero, what can you infer about the randomness of your sampling process?

In Exercises 3–8, find the critical value(s) and rejection region(s) for the type of t-test with level of significance alpha and sample size n.

Left-tailed test, α=0.10, n=20

In Exercises 13 and 14, (b) find the critical values,

Use

[APPLET] A highway patrol officer stops speeding vehicles on an interstate highway. The genders of the last 25 drivers who were stopped are shown, where F represents a female driver and M represents a male driver. Can you conclude that the stops were not random by gender?

F M M M F M F M F F F M M

F F F M M M F M M F F M

In Exercises 13 and 14, (c) find the test statistic,

Use

[APPLET] A highway patrol officer stops speeding vehicles on an interstate highway. The genders of the last 25 drivers who were stopped are shown, where F represents a female driver and M represents a male driver. Can you conclude that the stops were not random by gender?

F M M M F M F M F F F M M

F F F M M M F M M F F M

In Exercises 13 and 14, (d) decide whether to reject or fail to reject the null hypothesis, and (e) interpret the decision in the context of the original claim.

Use

[APPLET] A highway patrol officer stops speeding vehicles on an interstate highway. The genders of the last 25 drivers who were stopped are shown, where F represents a female driver and M represents a male driver. Can you conclude that the stops were not random by gender?

F M M M F M F M F F F M M

F F F M M M F M M F F M

Performing a Sign Test In Exercises 7–22, (a) identify the claim and state Ho and Ha, (b) find the critical value, (c) find the test statistic, (d) decide whether to reject or fail to reject the null hypothesis, and (e) interpret the decision in the context of the original claim.

Square Footage A renters’ organization claims that the median square footage of renter-occupied units is 1000 square feet. You randomly select 22 renter-occupied units and obtain the results shown above. At , can you reject the organization’s claim? (Adapted from U.S. Census Bureau)

[IMAGE]

Performing a Sign Test In Exercises 7–22, (a) identify the claim and state Ho and Ha, (b) find the critical value, (c) find the test statistic, (d) decide whether to reject or fail to reject the null hypothesis, and (e) interpret the decision in the context of the original claim.

Sales Prices of Homes A real estate agent claims that the median sales price of new privately owned one-family homes sold in Newark, New Jersey, in a recent month is $500,000 or less. The sales prices (in dollars) of 10 randomly selected homes are listed below. At , is there enough evidence to reject the agent’s claim? (Adapted from National Association of Realtors)

Age at First Marriage A marriage counselor claims that the median age of women at the time of their first marriage is less than or equal to 27 years old. In a random sample of 65 women, 24 were less than 27 years old, 35 were more than 27 years old, and 6 were 27 years old at the time of their first marriage. At α = 0.05, can you reject the counselor’s claim? (Adapted from U.S. Census Bureau)

Age at First Marriage A marriage counselor claims that the median age of men at the time of their first marriage is greater than 28 years old. In a random sample of 56 men, 33 were less than 28 years old and 23 were more than 28 years old at the time of their first marriage. At α = 0.05, can you support the counselor’s claim? (Adapted from U.S. Census Bureau)