The table below shows the mean number of daily errors by air traffic controller trainees during the first two weeks on the job.We want to perform a paired t-test at $\alpha$ = .05 to see if the mean daily errors decreased significantly. What would be the degrees of freedom for the appropriate test?
A) 14
B) 12
C) 7
D) 6

Question

Quizplus · Accepted Answer

The degrees of freedom for a paired t-test is n-1, where n is the number of pairs of data. In this case, there are 7 pairs of data, so the degrees of freedom is 7-1 = 6.

The Table Below Shows the Mean Number of Daily Errors α\alphaα

The Table Below Shows the Mean Number of Daily Errors $\alpha$