use mroz;
read all into y var{lwage};
read all into x var{one educ exper exper2};
read all into x1 var{educ};

/* instrument matrix includes all external and internal exogenous variables */
read all into z var {one exper exper2 mothereduc fathereduc}; * iv;
read all into z1 var {mothereduc fathereduc}; * external iv;
read all into z2 var {one exper exper2}; * included iv;
rname = {one educ exper exper2};

/* 2SLS Module */
*===============;
start tsls;
 n=nrow(y);
 k=ncol(x);
 k1=ncol(x1);
 l=ncol(z);
 l1=ncol(z1);
 xhat=z*inv(z`*z)*z`*x;
 biv=inv(xhat`*xhat)*xhat`*y;
 ehat=y-x*biv;
 sig2iv=ehat`*ehat/(n-k);
 covbiv=sig2iv*inv(xhat`*xhat);
 se=sqrt(vecdiag(covbiv));
 tstat=biv/se;
 pval=2*(1-probt(abs(tstat),n-k));
 result=biv||se||tstat||pval;
 cname={est se tstat pval};

 print / "2sls",, result [rowname=rname colname=cname format=13.6];
 finish;
 run tsls;