Re: [R] tansformation of variables in cph from rms package

On 26.02.2011 15:43, Frank Harrell wrote: Yao, I wonder how likely it is that log transformations fit the data. More often I find that the flexibility of restricted cubic splines is needed. One of the things that people take for granted when using log() is that they are assuming that k=0 in

Re: [R] tansformation of variables in cph from rms package

Yao, I wonder how likely it is that log transformations fit the data. More often I find that the flexibility of restricted cubic splines is needed. One of the things that people take for granted when using log() is that they are assuming that k=0 in making the transformation log(x + k). It is o

[R] tansformation of variables in cph from rms package

Dear all: I have used the cph function in the rms package. log10 was used to transform the variables, as follows: fit<-cph(pfsurv~log10(x1)+log10(x2),x=T,y=T,surv=T) after I run the nomogram function. I found "variable limits and transformations are such that an infinite axis value has resulted."