[R] Centring variables in Cox Proportional Hazards Model

2009-03-26 Thread Laura Bonnett
Dear All, I am contemplating centering the covariates in my Cox model to reduce multicollinearity between the predictors and the interaction term and to render a more meaningful interpretation of the regression coefficient. Suppose I have two indicator variables, x1 and x2 which represent age

Re: [R] Centring variables in Cox Proportional Hazards Model

2009-03-26 Thread Frank E Harrell Jr
Laura Bonnett wrote: Dear All, I am contemplating centering the covariates in my Cox model to reduce multicollinearity between the predictors and the interaction term and to render a more meaningful interpretation of the regression coefficient. Suppose I have two indicator variables, x1 and x2