The Quinnipiac University Pol conducts nationwide surveys as a public service and for research. This problem is baed on the results of one such poll that asked independent random samples of American adults in urban, suburban, and rural regions, "Do you support or oppose requiring background checks for all gun buyers?" Here are the results.

At the 1%significance level, do the data provide sufficient evidence to conclude that a difference exists in the proportions of supporters among the three regions?

Short Answer

Expert verified

We know, H0:p1=p2=p3(proportions of supporters are equal).

Ha:Not all the proportions of supporters are equal, α=0.01.

The test statistics is 11.520and the critical value is 9.210where P<0.005P=0.003. Also H0rejects at 1%significance level, the data provide sufficient evidence to conclude that a difference exists in a proportions of supporters among the three regions.

Step by step solution

01

Step 1. Given information.

Consider the given question,

02

Step 2. Consider the null and alternative hypotheses.

According to the null and alternative hypotheses,

H0denotes race distributions among the four U.S. regions are homogeneous.

Hαdenotes race distributions among the four U.S. regions are non-homogeneous.

The level of significance is α=0.01.

03

Step 3. Find the expected frequency and test statistics.

On finding the expected frequency and test statistics,

Pearson Chi-square=11.520,

df=2,p-value=0.003

Therefore, the value of Pearson chi-square is 11.520.

Therefore, the p-value is0.003.

04

Step 4. Consider the rejection rule.

Consider the rejection rule,

If P-valueα, then reject the null hypothesis.

Here, the P-value is lesser than the level of significance, P-value=0.003<α=0.01

Therefore, the null hypothesis is rejected at 1%level.

The results are statistically significant at the above given level of significance.

Hence, the data provide sufficient evidence to conclude that a difference exists in a proportions of supporters among the three regions at the 1%significance level.

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Most popular questions from this chapter

AIDS Cases. According to the Centers for Disease Control and Prevention publication HIV Surveillance Report, the number of AIDS cases in the United States in 2011, by region and race, is as shown in the following contingency table.

RegionWhiteBlackOtherTotal
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5043221
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