In order to construct an interval estimate of the difference in the means of two normally distributed populations with unknown but equal variances, using two independent samples of size n₁ and n₂, we must use a t distribution with (n₁+ n₂− 2)degrees of freedom.

Question

Quizplus · Accepted Answer

When constructing an interval estimate of the difference in the means of two normally distributed populations with unknown but equal variances using two independent samples, a t distribution is used. The degrees of freedom for this t distribution are calculated as the sum of the sample sizes of the two groups minus 2, which is represented as (n1 + n2 - 2).

In Order to Construct an Interval Estimate of the Difference