In the Accompanying Table, We Give the Smallest SSE for Each

Essay

In the accompanying table, we give the smallest SSE for each number of predictors k (k = 1,2,3,4) for a regression problem in which y=cumulative heat of hardening in cement, $x _ { 1 }$ =% tricalcium aluminate, $x _ { 2 }$ = % tricalcium silicate, $x _ { 3 }$ = % aluminum ferrate, and $$x _ { 4 }$$ = % dicalcium silicate. In addition, n=13, and SST=2715.16.
a. Use the criteria discussed in the text to recommend the use of a particular regression model.
b. Would forward selection result in the best two-predictor model? Explain.