sysuse auto, clear
regress mpg c.weight##c.gear_ratio
// Obtain means and standard deviation for plots
qui sum weight
local w_minsd = r(mean) - r(sd)
local w_mean = r(mean)
local w_plusd = r(mean) + r(sd)
qui sum gear_ratio
local g_minsd = r(mean) - r(sd)
local g_mean = r(mean)
local g_plusd = r(mean) + r(sd)
// Calculate predicted values for plot
margins, at(c.gear_ratio = (`g_minsd' `g_mean' `g_plusd') ///
c.weight = (`w_minsd' `w_mean' `w_plusd')) vsquish
// Plot
marginsplot, recastci(rarea) ciopts(color(gs10)) ///
title("Weight moderates the gear ratio{char 0150}mileage association") ///
xlabel(`g_minsd' "-1 SD" `g_mean' "Average gear ratio" `g_plusd' "+1 SD") ///
ytitle("Predicted mileage") ///
xtitle("Gear ratio") ///
plotopts(msymbol(none)) /// // Turn off markers
plot1opts(lpattern(longdash)) /// // Define line types here
plot2opts(lpattern(solid)) ///
plot3opts(lpattern(shortdash)) ///
legend(subtitle(Weight) ///
order(4 "- 1 SD" 5 "Mean" 6 "+ 1 SD" 2 "95% CI"))
// For some reason, marginsplot ignores the -label option-, therefore
// -order- is used here
gr export plot.png, as(png) replace
