When the necessary conditions are met, a two-tail test is being conducted to test the difference between two population proportions. If the value of the test statistic is 2.05, then the p-value is:
A) 0.4798
B) 0.0404
C) 0.2399
D) 0.0202
E) 0.1982

Question

Quizplus · Accepted Answer

A two-tail test means that we are interested in the possibility of there being a difference in proportions in either direction. With a test statistic of 2.05, we can find the p-value by looking up the area in the two tails of the appropriate t-distribution with the degrees of freedom determined by the sample sizes of the two populations. Using a calculator or a table, we can determine that the area in both tails is approximately 0.0404. Therefore, the p-value is 2 times the area in one tail, which is 0.0404*2 = 0.0808. However, since the question is asking for the p-value for a two-tail test, we must divide this by 2 to get the final answer of 0.0404.

When the Necessary Conditions Are Met, a Two-Tail Test Is