Refer to the data in Table P-18. Find the "best" regression model using the stepwise regression procedure and the all possible regressions procedure. Compare the results. Are you confident using a regression model to predict the final exam score with fewer than the original three independent variables?

TABLE P-18 x,x,x,Y|, ,, 87 85 27 91 93 60 3.2 54 100 84 33 90 92 69 3.1 63 91 82 3.5 83 100 86 36 96 85 60 3.7 93 80 87 3.5 89 56 64 28 43100 96 3.8 97 81 48 3.1 75 69 S1 2.8 50 77 67 3.1 63 80 75 3.6 74 86 73 3.0 7874 70 3.1 58 79 90 3.8 98 79 66 2.9 87 96 69 3.7 99 95 83 3.3 57