acfest lny_add , free( lnl ) proxy( lnm ) state( lnk ) robust va overid
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Ackerberg-Caves-Frazer Method to Estimate Production Functions
(Non-linear heteroskedastic GMM estimates for value added)
Number of obs = 1310
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| robust
lny_add | Coef. Std. Err. z P>|z| [95% Conf. Interval]
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lnk | .0887068 .0506598 1.75 0.080 -.0105846 .1879982
lnl | .9485465 .2745132 3.46 0.001 .4105106 1.486582
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Wald test of constant returns to scale: Chi2 = 0.02 (p = 0.8780)
Sargan-Hansen J-statistic: 0.925 (p = 0.6298)
H0: overidentifying restrictions are valid