* Calculate the mean and standard deviation, using 10 samples of
*    size 1000, from an empirical distribution, i.e. a bootstrap

use U:\STATA\nhis_ch6.dta , clear // No longer available
label var exfreqwR "Overall level of Physical Activity"
drop if exfreqwR == .
summarize exfreqwR

postfile results samp mean sd using results, replace
forvalue samp =  1/10 {
	preserve
	sample 1000, count
	summarize exfreqwR
	scalar mean=r(mean)
	scalar sd = r(sd)
	post results (`samp') (mean) (sd)
	restore
}
postclose results

clear
use results

summarize mean