Question

- In a random sample of 200 physicians, 36 were found to have an annual salary of at least $400,000.

1. Can you conclude that the ratio of a physician with an annual salary of at least $400,000 at a 1% significance level is less than 0.24? Test by hypothesis setting, rejection reverse setting, and calculation of test statistics.

2. Obtain a p value and explain how it can be used for hypothesis testing.

3. Obtain a 99% confidence interval estimate for the Moby rate of an internist with an annual salary of at least $400,000. Use this to explain how you can perform a hypothesis test.

- Marketing managers at one large multinational company are concerned that some salespeople perform well while others do very poorly. To analyse the problem, a random sample of 20 people was investigated, the sales allowance ($1,000) was determined and the following statistics were calculated: The sample mean, or average sales allowance, is $37.2 and the sample standard error is $7.8. Test whether these statistics provide enough evidence to conclude that the parent variance exceeds $35 (US$1 million) at a 5% significance level.

1. Set a hypothesis.

2. Set up rejection.

3. Obtain the test statistics.

4. Conclusion.

Answer 1

There is insufficient evidence to conclude that the ratio of a physician with an annual salary of at least $400,000 at a 1% significance level is less than 0.24.

3.

Problem 2:

these statistics provide enough evidence to conclude that the parent variance exceeds $35 at a 5% significance level.