set more off

use "/Users/dave/Desktop/lab3.dta", clear

/*

	Section 2

*/
ttest LDL, by(drinkany)
/*

	Section 3

*/
logistic drinkany smoking nonwhite age BMI
predict out, p
xtile group = out, nq(5)
/*

	Section 4

*/
tabulate drinkany group, col

table drinkany group, c(mean LDL)
/*

	Section 5

*/

reg LDL i.drinkany i.group

margins drinkany

margins, dydx(drinkany)
/*

	Section 6

*/
xtile group20 = out, nq(20)

reg LDL i.drinkany i.group20

margins drinkany
/*

	Section 7

*/
reg LDL i.drinkany smoking nonwhite age BMI
margins drinkany
/*

	Section 8

*/

mkspline agesp = age, nknots(5) cubic
mkspline bmisp = BMI, nknots(5) cubic

logit drinkany smoking nonwhite smoking##c.agesp* smoking##c.bmisp* nonwhite##c.agesp* nonwhite##c.bmisp*
predict outsp, p
xtile groupsp = out, nq(5)
reg LDL i. drinkany i.group
margins drinkany