Which of the following is not one of the assumptions of the t-test for independent samples?
A)The populations of raw scores form at least a roughly normal distribution.
B)There are two independent samples of interval/ratio scores.
C)There is homogeneity of variance.
D)The standard deviation of at least one of the populations is known.

Question

Quizplus · Accepted Answer

The t-test for independent samples does not require the standard deviation of the populations to be known. This is a key feature that distinguishes it from the z-test, which does require knowledge of the population standard deviation. The t-test instead estimates the standard deviation from the sample data.

Which of the Following Is Not One of the Assumptions