1. a. A researcher computes the regression equation for a sample of n = 25 pairs of scores, X and Y values. If an analysis of regression is used to test the signifi- cance of the equation, what are the df values for the F-ratio?
b. A researcher evaluating the significance of a regression equation obtains an F-ratio with df = 1, 18. How many pairs of scores, X and Y values, are in the sample?