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Are TV commercials louder than their surrounding programs? To find out, researchers collected data on 50randomly selected commercials in a given week. With the television’s volume at a fixed setting, they measured the maximum loudness of each commercial and the maximum loudness in the first 30seconds of regular programming that followed. Assuming conditions for inference are met, the most appropriate method for answering the question of interest is

a. a two-sample t test for a difference in means.

b. a two-sample t interval for a difference in means.

c. a paired t test for a mean difference.

d. a paired t interval for a mean difference.

e. a two-sample z test for a difference in proportions.

Short Answer

Expert verified

Option(e) A two-sample z test for a difference in proportions is the most appropriate method for this question.

Step by step solution

01

Given information

We need to find most appropriate method for answering the question.

02

Simplify

In general, we know that there is a one-sample z test for each proportion.
However, there is a two-sample z test for two proportions.
Similarly, there is one sample t test for one mean and two sample t tests or intervals or paired t tests or intervals for two means.

For checking a difference, equality, increase, or reduction, use a test.
To estimate an interval in which the true value lies, use an interval.
Therefore, a two-sample z test for a difference in proportions in this query because we need to estimate the difference between the two proportions.
As a result, option (e) is the proper choice.

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Most popular questions from this chapter

Literacy A researcher reports that 80%of high school graduates, but only 40%of high school dropouts, would pass a basic literacy test. Assume that the researcher’s claim is true. Suppose we give a basic literacy test to a random sample of 60high school graduates and a separate random sample of 75high school dropouts.p^G,p^Dbe the sample proportions of graduates and dropouts, respectively, who pass the test.

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a.(43)(0.3)1(0.7)33051526=0.200=20.0%43(0.3)1(0.7)3

b.(43)(0.3)3(0.7)13051526=0.200=20.0%43(0.3)3(0.7)1

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d.(0.3)3(0.7)13051526=0.200=20.0%(0.3)3(0.7)1

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A quiz question gives random samples of n=10observations from each of two Normally distributed populations. Tom uses a table of t distribution critical values and 9degrees of freedom to calculate a 95%confidence interval for the difference in the two population means. Janelle uses her calculator's two-sample t Interval with 16.87degrees of freedom to compute the 95%confidence interval. Assume that both students calculate the intervals correctly. Which of the following is true?

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