/****************************************************************
Fit a proportional hazards additive model (GAM) to melanoma data
May need to first install the gam package
net install gam, from(http://www.bioepi.altervista.org/stata), all
then move the .exe files into c:\ado\personal
*****************************************************************/
use melanoma, clear
keep if stage==1
stset surv_mm, fail(status==1)
gam _t age yydx sex, dead(_d) family(cox) df(4, sex:1) big
graph drop _all
twoway line s_age age, sort name(age) nodraw
twoway line s_yydx yydx, sort name(yydx) nodraw
graph combine age yydx