时变弹性系数生产函数的非参数估计

Nonparametric estimation of the production function with time-varying elasticity coefficients

提出了时变弹性系数生产函数模型,该模型刻画了弹性系数不再是常数而是随时间变化而变化的函数,并且去除了古典生产函数模型的两个不合理的假设,即所提出的模型释放了技术进步是中性的以及技术进步与投入要素投入量变化是独立的两个假设,从而使所提出的模型更加符合实际应用的情况.文中通过现代统计学中的非参数推断方法,研究了时变弹性系数生产函数回归模型,利用局部多项式回归方法,给出了时变弹性系数函数的局部线性加权最小二乘估计.根据广义似然比检验,检验了弹性系数的时变性.结合中国的实际例子,通过实证得出,在1981年到2004年期间,中国的资本和劳动产出弹性都不是常数而是时间的非线性函数.资本产出弹性在0.21至0.68之间,劳动产出弹性在0.44至0.89之间,规模报酬在0.89至1.14之间.

The production function regression models with time-varying elasticity coefficients are studied. The local linear weighted least squares estimators for time-varying elasticity coefficient functions are provided by the local polynomial regression method. For the real data example of China, the time-varying properties of the elasticity coefficients are studied. By the generalized likelihood ratio test, the capital output elasticity and the labor output elasticity in China are not constants but the nonlinear functions of the time in the period of 1981-2004 . The capital output elasticity varies from 0.21 to 0.68. The labor output elasticity varies from 0.44 to 0.89, and the return to scale varies from 0.89 to 1.14.