The data in the data frame compensation are from Myers (1990), Classical andModern Regression with Applications (Second Edition)," Duxbury. The response y here is executive compensation for the year 1979 for 33 rms, and x1-x3 are predictors. The data are discussed in the article by Guerard and Horton (1984), \The Management of Executive Compensation in Large, Dynamic Firms: A Ridge Regression Estimation," Technical Report, Lehigh University, Bethlehem, Penn sylvania.