Dear Statalisters:
I have a question about the bootstrapping command. I'm trying to
compare 2 means from populations with different sample sizes (n=400,
n=3000) using a t-test. The bootstrapping command should shuffle data
and generate t-values after each shuffle. This leads me to my question,
how does stata shuffle the data.
Does it take an equal subsample from each population (n=200 of the 400
and n=200 of the 3000) and calculate t or does it take an overall
subsample with an unequal number from each population (n=100 of 400 and
n=300 of 3000)?
This is the syntax that we are using:
program define TTestBoot
version 8.2
args AHI FWIN
ttest AHI == FWIN, unpaired
end
use "H:\ahifwin.dta", clear
bootstrap "TTestBoot AHI FWIN" T=r(t), reps(1000) saving
("H:\work\test.dta")
Any help would be appreciated.
Thanks.
Michael Malette
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