Dear List
I am trying to simulate data from two exponential distributions with a
certain hazard ratio in order to simulate a clinical trial. The code for
that part is working fine.
However, I want to now let the subjects enter using uniform entry rates over
a period of T years. Does anyone have any hints on how to do this?
Posted below is the simulation program as it stands without uniform entry:
capture program drop sampsim
program define sampsim
postfile samp chi2 using sampres, replace
forvalues i=1/1000 {
quietly dosampsim
}
postclose samp
end
capture program drop dosampsim
program define dosampsim
drop _all
set obs 16
gen byte group = _n<=(_N/2)
gen x=-log(uniform()) if group==0
replace x=-(1/3.5)*log(uniform()) if group==1
stset x
sts test group
post samp (r(chi2))
end
set seed 59382
sampsim
program drop sampsim dosampsim
exit
Thank you for your help!
Sophie Barthel
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