set more off
capture log close
clear

// ***************** paths *******************************
local misenda = "/home/ricmora/AAOFICIN/CURSOS/MADE/materiales/slides"

set seed 27031967
set obs 5000
matrix mu = (0,0)
matrix sigma = (1,0.5\0.5,1)

// generate variables
gen u =uniform()
gen kids = (u>0.25) + (u>0.75)
gen educ=8*(u<=.15)+12*(u>.15)*(u<=.6)+16*(u>.6)*(u<=.9)+21*(u>.9)
gen h_star= 5+0.5*educ-5*kids+7*rnormal()
gen h=(h_star>0)*h_star

// estimate with different models
regress h educ kids
test (educ=0.5) (kids=-5)
regress h educ kids if h>0
test (educ=0.5) (kids=-5)
tobit h educ kids, ll(0)
test (educ=0.5) (kids=-5)
mfx

// estimate the marginal effect on average actual hours worked of an extra child
predict x0b, xb
replace kids=kids+1
predict x1b, xb
gen Mg_kid=(x1b>0)*x1b - (x0b>0)*x0b

su Mg_kid
exit