/* for use after gmm with demeaned factors */

/* pc errors with demeaned factors */
pcerr1 = meanc(m.*allr)/meanc(m);
pcerr1a = (eye(cols(allr))-covs'*inv(covs*covs')*covs)*meanc(allr);

/* pc errors with same reti, no demeaned factors */
c2 = covs + meanc(reti)*meanc(allr)';
b2 = -invpd(c2*c2')*c2*meanc(allr)*b0;
m2 = b0 + reti*b2;
pcerr2 = meanc(m2.*allr)/meanc(m2);
pcerr2a = (eye(cols(allr))-c2'*invpd(c2*c2')*c2)*meanc(allr)/
         (1-meanc(reti)'*invpd(c2*c2')*c2*meanc(allr) );
1000*(pcerr1~pcerr1a~pcerr2~pcerr2a);