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Chapter 12: Q. 31 (page 804)

A city wants to conduct a poll of taxpayers to determine the level of support for constructing a new city-owned baseball stadium. Which of the following is the primary reason for using a large sample size in constructing a confidence interval to estimate the proportion of city taxpayers who would support such a project?

(a) To increase the confidence level

(b) To eliminate any confounding variables

(c) To reduce nonresponse bias

(d) To increase the precision of the estimate

(e) To reduce under coverage

Short Answer

Expert verified

The reason is to increase the precision of the estimate i.e., option (d).

Step by step solution

01

Given Information

We are given that a city wants to conduct a poll of taxpayers to determine the level of support for constructing a new city-owned baseball stadium and we have to find out the reason for using a large sample size.

02

Explanation

Now as we know that as the sample size increases, the estimation will also be more precise and thus this is the reason of using a large sample size in constructing a confidence interval to estimate the proportion of city taxpayers who would support such a project.

Hence, option (d) is correct

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