In checking normality assumptions for using the t test when σ is not known,which of the following is not true?
A)The sample mean is close to the sample median.
B)The normal probability plot is approximately a straight line.
C)The sample size to be used is not a factor.
D)The boxplot of the sample appears approximately symmetrical.

Question

Quizplus · Accepted Answer

The sample size can actually affect the normality assumptions for the t test when σ is not known. If the sample size is very small (less than 15), the normality assumptions might not hold even if the other conditions are met. Therefore, the statement that "the sample size to be used is not a factor" is not true. The other statements (A, B, and D) are all true normality assumptions for the t test when σ is not known.

In Checking Normality Assumptions for Using the T Test When