Which of the following is NOT a required assumption for constructing a confidence interval estimate of the difference between two population means when the samples are small?
A) The populations are normally distributed.
B) The population variances are equal.
C) The population variances are both equal to 1.
D) The samples are selected at random from the populations.

Question

Quizplus · Accepted Answer

The assumption that the population variances are both equal to 1 is not a required assumption for constructing a confidence interval estimate of the difference between two population means when the samples are small. The required assumptions are that the populations are normally distributed, the population variances are equal (or the sample sizes are equal and the populations are normal), and the samples are selected at random from the populations.

Which of the Following Is NOT a Required Assumption for Constructing