is the degree of freedom of the pooled test always less than the df of the pooled t-test? what is welch test equal to does welch test always reduce standard deviation what degree of freedom does welch test always reduce is degree of freedom always less than df when does the degrees of freedom in the pooled test always change after welch test what is the pooled test in math why are welch's tests always less than pooled testing what is welch test df how do welch test degrees of freedom work in math does welch test always lower degrees of freedom does the pooled welch test reduce the degrees of freedom how is the degrees of freedom used in welch's test what is degree of freedom in welch test why is it necessary to use welch test which measure of freedom should be used for the standard deviations of the pooled test? what is the degree of freedom of a pooled t test what is the value of df in welch test welch test degrees of freedom example what is the value of welch test when the variance is equal in welch test