st: re-running a program and saving results

[Michael McCulloch <mm@pinest.org>]

Dear Statalist members,
I've written the following simple program, which will estimate the 
hazard ratio from a large simulated dataset containing 10,000 
observations.

I'd like to ask for suggestions on how to modify my program so that it will:

1. Draw random samples from the dataset in memory, 1,000-observation intervals,
2. save the results (hazard ratio and confidence interval), and then
3. plot the results showing how the analysis performs on sample sizes 
of 1,000, 2,000, 3,000 and so on up to 10,000.

This is the first program I've written, so not sure how to go about 
this. I imagine it's something concise at the very last line?

capture program drop pcox
	version 9.2
	program define pcox, rclass
	tempname a

	* stset the data
	stset risktime, failure(failed==1)

	* cox
		stcox a
	indeplist, local
	foreach var of varlist `X' {
		return scalar `var' = exp(_b[`var'])
	}

end
set seed 12358
bootstrap a=r(a), eform reps(10): pcox

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