Suppose a package delivery company purchased 14 trucks at the same time. Five trucks were purchased from manufacturer A, four from manufacturer B, and five from manufacturer C. The cost of maintaining each truck was recorded. The company used ANOVA to test if the mean maintenance costs of the trucks from each manufacturer were equal. To apply the F test, how many degrees of freedom must be in the denominator?

Question

Quizplus · Accepted Answer

The denominator degrees of freedom in an ANOVA F test is calculated as the total number of observations minus the number of groups. Here, there are 14 trucks (total observations) and 3 manufacturers (groups), so the degrees of freedom in the denominator is 14 - 3 = 11.

Suppose a Package Delivery Company Purchased 14 Trucks at the Same