Principal Components Regression
"Principal Components Regression" (PCREG), also sometimes called "biased regression methods" is used to model data with highly correlated explanatory variables. This well-known method has been discussed by multiple previous authors (Marquardt 1970, Hoerl and Kennard 1970, Lott 1973, Hawkins 1973, Webster, Grace and Mason 1974, Hoerl, Kennard and Baldwin 1975, Marquardt and Snee