A radio talk show host with a large audience is interested in the proportion pof adults in his listening area who think the drinking age should be lowered to eighteen. To find this out, he poses the following question to his listeners: "Do you think that the drinking age should be reduced to eighteen in light of the fact that eighteen-year-olds are eligible for military service?" He asks listeners to phone in and vote "Yes" if they agree the drinking age should be lowered and "No" if not. Of the 100people who phoned in, 70answered "Yes." Which of the following conditions for inference about a proportion using a confidence interval are violated?

I. The data are a random sample from the population of interest.

II. nis so large that both npandn1-pare at least 10.

III. The population is at least 10times as large as the sample.

(a) I only

(c) III only

(c) I, II, and III

(b) II only

(d) I and II only

Short Answer

Expert verified

(a) I only

Step by step solution

01

Step-1 Given Information

Given in the question that,

number of success (X)=70

number of trials(n)=100we have to find the correct option.

02

Step-2 Explanation

Here, sampling has been using the method of voluntary response sample and one of the conditions to create the confidence interval for population proportion is that the sample should be selected using the technique of simple random sampling. Thus, the condition of simple random sample is not met here.

Hence, the correct option is (a).

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Most popular questions from this chapter

School vouchers A national opinion poll found that 44% of all American adults agree that parents should be given vouchers that are good for education at any public or private school of their choice. The result was based on a small sample.

(a) How large an SRS is required to obtain a margin of error of 0.03(that is, ±3%) in a 99% confidence interval? Answer this question using the previous poll’s result as the guessed value for p.

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In a poll,

I. Some people refused to answer questions.

II. People without telephones could not be in the sample.

III. Some people never answered the phone in several calls.

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