The purpose of model selection algorithms such as All Subsets, Forward Selection, and Backward Elimination is to choose a linear model on the basis of the same set of data to which the model will be applied. Typically we have available a large collection of possible covariates from which we hope to select a parsimonious set for the eificient pre- diction of a response variable. Least Angle Regression (" LARS"), a new model selection algorithm, is a useful and less greedy version of...