An advertising company has developed a new ad for one of the national car manufacturing companies. The ad agency is interested in testing whether the proportion of favorable response to the ad is the same between male adults versus female adults. It plans on conducting the test using an alpha level equal to 0.05. A sample of 100 adults of each gender will be used in the study. Each person will be asked to view the ad and indicate whether they find the ad to be "pleasing" or not. Given this information, what is the critical value?
A) z = 1.645
B) t = 1.96
C) z = 1.96
D) Can't be determined without knowing the results of the sample.

Question

Quizplus · Accepted Answer

The critical value for a two-tailed test with an alpha level of 0.05 using the z-distribution is z = 1.96. This is because the question implies a comparison of proportions (favorable responses) between two independent groups (male vs. female adults), which typically uses a z-test when sample sizes are large (n ≥ 30 for each group), and the population standard deviation is unknown but approximated by the sample.

An Advertising Company Has Developed a New Ad for One