I ran a Cox-Regression on Prepayment analysis. Right now, I'm using a stratified Cox-Regression with time dependent variables. The focus of my work lays NOT on prediction but rather on differentiating among risk groups.
The problem is that my p-values are extreme low, while my (pseudo) R-square is extremely low, around 0.001 (max 0.225) . Concordance is around 0.50
What do these results tell me? I heard different comments on the R-Square measure. Some say that it is complete meaningless since it does not handle censored data correctly (same for concordance)
Can I simply ignore this measures? Or is there one way to push R-Square?