Tennis magazine (Feb. 2000) claims that "tennis players who tie the knot often see their games unravel." The next table lists a sample of players and their rankings on their wedding days and on their first anniversaries.

a. Construct a scattergram for these data. Does it tend to support or refute the magazine's claim? Justify your answer.

b. Use the method of least squares to construct a model of the relationship between wedding day ranking (x)

and first anniversary ranking (y).

c. Does the linear model you developed in part b contribute information for predicting players' rankings on their first anniversaries? Test at a = .05.

d. If there were no changes whatsoever in the rankings of the sample of players after getting married, what would the true values of P,, and P, be?