R help - Nov 2006 - Extracting parameters for Gamma Distribution

I'm doing a cox regression with frailty:

model <- coxph(Surv(Start,Stop,Terminated)~ X + frailty(id),table)

I understand that model$frail returns the group level frailty 
terms. Does this mean this is the average of the frailty 
values for the respective groups? Also, if I'm fitting it to
a gamma frailty, how do I extract the rate and scale 
parameters for the different gamma distributions fit to each
group? Thanks.

Yongchuan

On Tue, 7 Nov 2006, yongchuan wrote:
> I'm doing a cox regression with frailty:
>
> model <- coxph(Surv(Start,Stop,Terminated)~ X + frailty(id),table)
>
> I understand that model$frail returns the group level frailty
> terms. Does this mean this is the average of the frailty
> values for the respective groups?
It is the frailty value that is common to all the measurements with the 
same id value.
> Also, if I'm fitting it to
> a gamma frailty, how do I extract the rate and scale
> parameters for the different gamma distributions fit to each
> group? Thanks.
There are not different gamma distribution fit to each group. There is one 
gamma distribution.

 	-thomas