* Simple random sampling use http://www.ats.ucla.edu/stat/books/sop/momsag.dta, clear list birth weight1 momsag in 1/10 svyset pweight weight1 svyset fpc birth svymean momsag svyset, clear svyset ci momsag di sqrt((773-25)/773)*.0553775 * fpc multiplied by the standard error for mean svyset pweight weight1 svyset fpc birth svytotal momsag * Stratified random sampling use http://www.ats.ucla.edu/stat/books/sop/hospsamp.dta, clear list in 1/10 svyset pweight weighta svyset strata oblevel svyset fpc tothosp svytotal births svytotal births, by (oblevel) * one-stage cluster sampling use http://www.ats.ucla.edu/stat/books/sop/tab9_1a.dta, clear list devlpmnt HH wt1 M NVSTNRS NGE65 hhneedvn in 1/10 svyset pweight wt1 svyset fpc M svyset psu devlpmnt svytotal NVSTNRS NGE65 svymean NVSTNRS hhneedvn svyratio NVSTNRS NGE65