When calculating the standard error of ,under what assumption do you pool the sample variances and ?
A)Known population variances
B)Unknown population variances that are assumed equal
C)Unknown population variances that are assumed unequal
D)All of the above

Question

When calculating the standard error of  ,under what assumption do you pool the sample variances  and  ?
A)Known population variances 
B)Unknown population variances that are assumed equal 
C)Unknown population variances that are assumed unequal 
D)All of the above

Quizplus · Accepted Answer

When calculating the standard error, we assume that the population variances are unknown and equal. Therefore, we use pooled sample variances to estimate the true variance of the population. Option A is not applicable as we are assuming unknown population variances. Option C is also incorrect as we assume equal population variances in this case. Option D is not correct as we are not assuming known population variances. Therefore, the best choice is B.

When Calculating the Standard Error of ,Under What Assumption