In testing the difference between two population means for which the population variances are unknown and assumed to be equal, two independent samples are drawn from the populations. Which of the following tests is appropriate?
A) z-test.
B) Equal-variances t-test.
C) F-test.
D) Matched pairs t-test.

Question

Quizplus · Accepted Answer

The equal-variances t-test (also known as the two-sample t-test) is appropriate in this situation when the population variances are unknown and assumed to be equal. This test uses the t-distribution to compare the means of the two independent samples. The z-test is only appropriate when the population variances are known, the F-test is used for testing the equality of variances, and the matched pairs t-test is only appropriate when the two samples are not independent (e.g., before-after measurements on the same group).

In Testing the Difference Between Two Population Means for Which