چکیده:
Productivity is often computed by approximating the weighted sum of
the inputs from the estimation of the Cobb-Douglas production
function. Such estimates, however, may suffer from simultaneity and
selection biases. Olley and Pakes (1996) introduced a semi-parametric
method which allows us to estimate the production function parameters
consistently and thus obtain reliable productivity measures by
controlling for such biases. This study first reviews this method and then
introduces a Stata(10) command to implement it for manufacturing
industry in Iran. The results show that material, skill labor and capital
play important role in production function and this is increasing return to
scale (IRS) by estimation of Olley and Pakes approach versus decreasing
return to scale (DRS) by fixed effect. After estimation of production and
calculated total factor productivity (TFP), we concluded that the effect
of export and exit rate on TFP at manufacturing industry (ISIC 4digits)
in Iran is not very considerable to compare to import penetration
coefficient and year effect.
خلاصه ماشینی:
"The Impact of Trade Liberalization on Iran's Manufacturing TFP: An Application of Olley -Peaks Approach Abbas Aminifard 1 Karim Azarbaijani 2 Seyed Komail Tayebi 3 Abstract P roductivity is often computed by approximating the weighted sum of the inputs from the estimation of the Cobb-Douglas production function.
The results show that material, skill labor and capital play important role in production function and this is increasing return to scale (IRS) by estimation of Olley and Pakes approach versus decreasing return to scale (DRS) by fixed effect.
After estimation of production and calculated total factor productivity (TFP), we concluded that the effect of export and exit rate on TFP at manufacturing industry (ISIC 4digits) in Iran is not very considerable to compare to import penetration coefficient and year effect.
Following Olley and Pakes, we estimate a Cobb-Douglas production function, taking the logs of equation 1, which we denote by small letters, (2) The error term, , has two components, a white noise component, , and a time varying productivity shock, , which is known to the firm, but not to the econometrician.
4- Model and Estimation Strategy To determine the effect of trade liberalization on productivity, we consider a plant with a Cobb-Douglas production function, (1) Where output in firm at time ,, is a function of skilled labor, , unskilled labor, , capital, , and materials,.
Using the plant level measures of TFP from equation (5), we estimate the following equation: (6) Where LX, Year, Exit and IMPP are the respective logarithms of real export, year effect, exit dummy variable and import penetration and estimates obtained from Arrelano and bond dynamic panel data method."