webuse hsng2, clear
sum hsngval // Get avg. and SD
// OLS
regress rent pcturban hsngval faminc i.region
margins, at(hsngval = (32714 48484 64254)) saving(ols, replace)
// IV
ivregress 2sls rent pcturban (hsngval = faminc i.region)
margins, at(hsngval = (32714 48484 64254)) saving(iv, replace)
// Plot
combomarginsplot ols iv, labels("OLS" "IV") ///
title("{bf:A}", span bexpand justification(left)) ///
xtitle(Median housing value) ///
ytitle(Median gross rent) ///
xlabel(48484 "Avg." 64254 "+1 SD" 32714 "-1 SD") ///
recastci(rarea) ciopt(color(%30) lcolor(white)) ///
legend(pos(11) ring(0)) ///
scheme(lean1) name(ols_iv_predictions, replace)
