Neurosurgery Operative Times. In Example 10.6 on pages 482–484, we conducted a nonpooled t-test, at the 5% significance level, to decide whether the mean operative time is less with the dynamic system than with the static system. Use the technology of your choice to perform the following tasks.

a. Using a pooled t-test, repeat that hypothesis test.

b. Compare your results from the pooled and nonpooled t-tests.

c. Repeat both tests, using a 1% significance level, and compare your results.

d. Which test do you think is more appropriate, the pooled or nonpooled t-test? Explain your answer.

Working with Large Data Sets