Data Set 13-5: An F value of 2.75 was obtained when an interaction mean square was divided by a error mean square. The degrees of freedom were 4 and 24.
-Refer to Data Set 13-5. The number of independent variables in this design must have been
A) 1
B) 2
C) 3
D) none of the other alternatives are correct.

Question

Quizplus · Accepted Answer

The degrees of freedom for the interaction term (4) suggest a 2x2 factorial design, implying there are 2 independent variables. Each variable has 2 levels, and the interaction term's degrees of freedom are calculated as (levels of IV1 - 1) * (levels of IV2 - 1) = (2-1)*(2-1) = 1*1 = 1 for each combination, but given the degrees of freedom is 4, it suggests there are multiple combinations, consistent with 2 independent variables.

Data Set 13-5: an F Value of 2