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Chapter 7: Q.24 (page 431)

Increasing the sample size of an opinion poll will

(a) reduce the bias of the poll result.

(b) reduce the variability of the poll result.

(c) reduce the effect of nonresponse on the poll.

(d) reduce the variability of opinions.

(e) all of the above.

Short Answer

Expert verified

A correct answer is an option (b) to reduce the variability of opinions.

Step by step solution

01

Given Information

Increasing the sample size of an opinion poll.

02

Explanation

A larger sample size results in more information about the population and thus better estimates of the population.

If we have better estimates of the population, then we also know that there is less variability.

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Most popular questions from this chapter

Social scientists are interested in the association between the high school graduation rate (HSGR) and the percentage of U.S. families living in poverty (POV). Data were collected from all 50states and the District of Columbia, and a regression analysis was conducted. The resulting least-squares regression line is given by POV=59.2-0.620(HSGR) with r2=0.802. Based on the information, which of the following is the best interpretation for the slope of the least-squares regression line?

(a) For each 1%increase in the graduation rate, the per cent of families living in poverty is predicted to decrease by approximately 0.896.

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(d) For each1%increase in the percentage of families living in poverty, the graduation rate is predicted to increase by approximately 0.802.

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