What is the number of degrees of freedom in each of the foll

What is the number of degrees of freedom in each of the following?

A. a sample of 10 observations

B. a sample of 100 observations

C. a sample of 250 observations

D. a sample of 1000 observations

Solution

The degrees of freedom of an estimate of variance is equal to N - 1, where N is the number of observations

A. df=9

B. df=99

C. df=249

D. df=999