therneau at mayo.edu
Thu Feb 26 15:28:45 CET 2009
> plot(survfit(fit)) should plot the survival-function for x=0 or
> equivalently beta'=0. This curve is independent of any covariates.
This is not correct. It plots the curve for a hypothetical subject with x=
mean of each covariate.
This is NOT the "average survival" of the data set. Imagine a cohort made up
of 60 year old men and their 10 year old grandsons: the expected survival of
this cohort does not look that for a 35 year old male.
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