Which of the following are assumptions underlying the use of the t test for independent groups?
A) the variance of each population is known
B) the sampling distribution of must be normal
C) the samples are drawn from populations having equal variances
D) all of these
E) the sampling distribution of must be normal and the samples are drawn from populations having equal variances

Question

Which of the following are assumptions underlying the use of the t test for independent groups?
A) the variance of each population is known 
B) the sampling distribution of must be normal 
C) the samples are drawn from populations having equal variances 
D) all of these 
E) the sampling distribution of must be normal and the samples are drawn from populations having equal variances

Quizplus · Accepted Answer

The assumptions underlying the use of the t test for independent groups are that the sampling distribution of the difference between the two means must be normal and the samples are drawn from populations having equal variances. Therefore, choice E is the best choice as it includes both of these assumptions. Choice A is incorrect because the variance of each population does not need to be known, and choice B is incorrect because the sampling distribution of the means (not a specific sample) must be normal. Choice C is also incorrect because the populations do not need to have equal variances, only the assumption of equal variances needs to be met for the calculation of the t statistic.

Which of the Following Are Assumptions Underlying the Use of the T