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Chapter 9: Q 18. (page 565)

Don’t argue Refer to Exercises 2 and 12.

a. What conclusion would you make at the α=0.01 level?

b. Would your conclusion from part (a) change if a 5% significance level was used

instead? Explain your reasoning.

Short Answer

Expert verified

a. The evidence is present that percentage of teens in school that claim that they never argue with friends is different from 72%

b. From the given condition here, the conclusion is changed.

Step by step solution

01

Given Information

It is given that P=0.0291=2.91%

α=0.01

Proportion is72%

02

To find the conclusion at α=0.01 level

Claim can be null of alternative hypothesis.

Null Hypothesis is the population proportion is value given in claim. Alternative hypothesis is opposite of null hypothesis.

H0:p=72%=0.72

H1:p≠0.72

If pvalue<α, null hypothesis is rejected.

0.0291<0.01⇒Fail to rejectH0

Hence, the evidence is present that percentage of teens in school that claim that they never argue with friends is different from 72%

03

If above conclusion changed if 5% significance level is used

If significance level is 5%=0.05

Here 0.0291<0.05,rejectH0

The conclusion is changed.

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Most popular questions from this chapter

You are testing H0:μ=10 against Ha:μ≠10 based on an SRS of 15

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