The ROBUSTREG procedure has the following main features:
offers four estimation methods: M, LTS, S, and MM
provides 10 weight functions for M estimation
provides robust R square and deviance for all estimates
provides asymptotic covariance and confidence intervals for regression parameters by using the M, S, and MM methods
provides robust Wald and F tests for regression parameters by using the M and MM methods
provides Mahalanobis distance and robust Mahalanobis distance by using the generalized minimum covariance determinant (MCD) algorithm
provides outlier and leverage-point diagnostics
supports parallel computing for S and LTS estimates
supports constructed effects, including spline and multimember effects
produces fit plots and diagnostic plots by using ODS Graphics