Given here are data for a dependent variable and four potential predictors. Use these data and a stepwise regression procedure to develop a multiple regression model to predict y. Examine the values of t and R2 at each step and comment on those values. How many steps did the procedure use? Why do you think the process stopped?

y x1 x2 x3 x4 101 2 77 1.2 42 127 4 72 1.7 26 98 9 69 2.4 47 79 5 53 2.6 65 118 3 88 2.9 37 114 1 53 2.7 28 110 3 82 2.8 29 94 2 61 2.6 22 96 8 60 2.4 48 73 6 64 2.1 42 108 2 76 1.8 34 124 5 74 2.2 11 82 6 50 1.5 61 89 9 57 1.6 53 76 1 72 2.0 72 109 3 74 2.8 36 123 2 99 2.6 17 125 6 81 2.5 48