roger webb
 
> I need to run a Cox model on a very large cohort (of approximately
> 1.5 million subjects). Has anyone implemented a memory efficient
> routine that uses a sample from (as opposed to all) the individuals
> at risk?
Nothing to do with me, but I doubt that there 
is amy special procedure needed here. That is,
you just should take a sample upstream and then 
fit a Cox model on the sample data, I guess. 
Nick 
[email protected] 
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