- A Simple Random Sample Of Front Seat Occupants Involved In Car Crashes Is Obtained Among 2974 Occupants Not Wearing Sea 1 (45.72 KiB) Viewed 84 times
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A simple random sample of front-seat occupants involved in car crashes is obtained. Among 2974 occupants not wearing seat belts, 38 were killed. Among 7673 occupants wearing seat belts, 17 were killed. Use a 0.05 significance level to test the claim that seat belts are effective in reducing fatalities. Complete parts (a) through (c) below. a. Test the claim using a hypothesis test. Consider the first sample to be the sample of occupants not wearing seat belts and the second sample to be the sample of occupants wearing seat belts. What are the null and alternative hypotheses for the hypothesis test? ỌC. Ho: PizPz O B. O A. Ho: P₁ P₂ H₁: P₁ = P2 Ho: P1-P2 H₁: P1 H₁: P₁ P₂ P2 O E. Ho: P₁ P₂ OF. Ho: P1 = P2 H₁: P₁ P2 O D. Ho: P₁ P2 H₁: P1 P2 H₁: P₁ P2
Identify the test statistic. z = 6.67 (Round to two decimal places as needed.) Identify the P-value. P-value = 0.000 (Round to three decimal places as needed.) What is the conclusion based on the hypothesis test? ▼ The P-value is less than the significance level of a = 0.05, so the null hypothesis. There b. Test the claim by constructing an appropriate confidence interval. The appropriate confidence interval is 0.007 < (P₁-P₂) < 0.015. (Round to three decimal places as needed.) What is the conclusion based on the confidence interval? Because the confidence interval limits do not include 0, it appears that the two fatality rates are not equal. Because the confidence interval limits include only positive higher for those not wearing seat belts. reject is sufficient evidence to support the claim that the fatality rate is higher for those not wearing seat belts. values, it appears that the fatality rate is
c. What do the results suggest about the effectiveness of seat belts? A. The results suggest that the use of seat belts is associated with the same fatality rates as not using seat belts. B. The results suggest that the use of seat belts is associated with lower fatality rates than not using seat belts. C. The results suggest that the use of seat belts is associated with higher fatality rates than not using seat belts. OD. The results are inconclusive.