Question

. A Pew Research Center poll asked randomly selected subjects if they agreed with the statement that “It is morally wrong for married people to have an affair.” Among the 386 women surveyed, 347 agreed with the statement. Among the 359 men surveyed, 312 agreed with the statement. Use a 0.05 significance level to test the claim that the percentage of women who agree is the same as the percentage of men who agree.

Answer 1

Sample 1 be female

Sample 2 be e male

For sample 1, we have that the sample size is N_1= 386 , the number of favorable cases is X_1 = 347 , so then the sample proportion is

For sample 2, we have that the sample size is N_2 = 359 , the number of favorable cases is X_2 = 312 , so then the sample proportion is

The value of the pooled proportion is computed as

Also, the given significance level is α=0.05.

(1) Null and Alternative Hypotheses

The following null and alternative hypotheses need to be tested:

This corresponds to a two-tailed test, for which a z-test for two population proportions needs to be conducted.

(2) Rejection Region

Based on the information provided, the significance level is α=0.05, and the critical value for a two-tailed test is z_c = 1.96

(3) Test Statistics

The z-statistic is computed as follows:

(4) Decision about the null hypothesis

Since it is observed that |z| = 1.275 ≤zc​=1.96, it is then concluded that the null hypothesis is not rejected.

Using the P-value approach: The p-value is p = 0.2022 , and since p = 0.2022 ≥0.05, it is concluded that the null hypothesis is not rejected.

(5) Conclusion

It is concluded that the null hypothesis Ho is not rejected. Therefore, there is not enough evidence to claim that the population proportion p1​ is different than p2​, at the 0.05 significance level.