Question

What is Welch's t-test?

Answer 1

A Welch's t-test is a modification of the t-test that determines if the means of two groups are significantly different from one another.

Explanation:

A Welch's t-test is a modification of the t-test that determines if the means of two groups are significantly different from one another. It is also called the Welch's test for unequal variances. Unlike a t-test which assumes that variances are equal, the Welch's test does not and it adjusts the degrees of freedom. (Both tests assume normal distribution .)

When variances are equal, the Student's t-test and the Welch's t-test should return the same results.