1. The scatterplot and least-squares regression line for predicting 1. Y from X is given in the figure below for the following pairs of scores from a pretest and posttest:

(a) Use a straightedge with the regression line to estimate (to one decimal place) the predicted Y score (Yˆ ) of each student.

(b) Use the answers from Problem 1a to determine the error in prediction for each student.

(c) Use the answers from Problem 1b to compute the error sum of squares.

(d) If any other line were used for prediction, how would the error sum of squares compare with your answer to Problem 1c?