use "C:\Users\nojko\Dropbox\My PC (DESKTOP-35V8EGV)\Documents\EMUPP_2021\mroz_data.dta" 
regress lwage educ exper expersq, robust
ivregress 2sls lwage  exper expersq (educ= motheduc fatheduc)
regress lwage educ exper expersq, robust
estimate store lwageols
ivregress 2sls lwage  exper expersq (educ= motheduc fatheduc)
estimate store lwageiv
regress lwage educ exper expersq
estimate store lwageols
ivregress 2sls lwage  exper expersq (educ= motheduc fatheduc)
estimate store lwageiv
hausman lwageols lwageiv, constant
estat endogenous
estat overid
estat firststage