Question

A researcher conducts a hypothesis test using a sample of n = 40 from an unknown population. What is the df value for the t statistic?

a. 38
b. 39
c. 40
d. 41

Answer 1

Correct option: b 39.

Explanation:

A one-sample (or one mean) t-test is applied to test whether the population-parameter is significantly different from some hypothetical value.

The degrees of freedom of the t-test is:

df = n - 1

It is provided that the sample size is, n = 40.

Compute the degrees of freedom as follows:

df = n - 1

= 40 - 1

= 39

Thus, the correct option is b.