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Chapter 9 Quize
CHAPTER EIGHT

INTERVAL ESTIMATION

MULTIPLE CHOICE QUESTIONS

In the following multiple choice questions, circle the correct answer.

1. When s is used to estimate (, the margin of error is computed by using a. normal distribution b. t distribution c. the mean of the sample d. the mean of the population Answer: b

2. As the number of degrees of freedom for a t distribution increases, the difference between the t distribution and the standard normal distribution a. becomes larger b. becomes smaller c. stays the same d. None of these alternatives is correct. Answer: b

3. For the interval estimation of ( when ( is known and the sample is large, the proper distribution to use is a. the normal distribution b. the t distribution with n degrees of freedom c. the t distribution with n + 1 degrees of freedom d. the t distribution with n + 2 degrees of freedom Answer: a

4. An estimate of a population parameter that provides an interval of values believed to contain the value of the parameter is known as the a. confidence level b. interval estimate c. parameter value d. population estimate Answer: b

5. The value added and subtracted from a point estimate in order to develop an interval estimate of the population parameter is known as the a. confidence level b. margin of error c. parameter estimate d. interval estimate Answer: b

6. If an interval estimate is said to be constructed at the 90% confidence level, the confidence coefficient would be a. 0.1 b. 0.95 c. 0.9 d. 0.05 Answer: c

7. Whenever the population standard deviation is unknown and the population has a normal or near-normal distribution, which distribution is used in developing an interval estimation? a. standard distribution b. z distribution c. alpha distribution d. t distribution Answer: d

8. In interval estimation, the t distribution is applicable only when a. the

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