中国大中城市蔬菜生产技术效率提高了吗?——基于超越对数随机前沿模型的分析

Did the Technical Efficiency of Vegetable Production Improved in China's Large and Medium Cities?——Analysis Based on the Trans-log Stochastic Frontier Production Function Model

文章基于区域特征、时序特征、种植特征、产业特征和环境特征的超越对数生产函数随机前沿模型,运用2001—2014年大中城市面板数据,测度蔬菜生产技术效率、演变规律并分析影响因素。结果发现:1)2001—2014年间蔬菜生产技术效率呈波动上升的趋势,虽然生产技术效率从东部至西部存在显著的"阶梯现象",但是地域差异的变动趋势并未形成马太效应。2)城市规模的扩大对于蔬菜生产技术效率而言只有水平效应,而并没有显著的增长效应。不同规模的城市、不同种植方式特征的蔬菜生产技术效率还存在组间差异和组内差异。3)我国蔬菜生产投入资源存在错配的现象,无论对于总体蔬菜、设施蔬菜还是露地蔬菜,其资本产出弹性均呈波动下降的趋势。虽然设施蔬菜生产技术效率高于露地蔬菜生产技术效率,但是设施蔬菜各投入要素呈现规模报酬递减的趋势,露地蔬菜各投入要素呈现规模报酬波动上升的趋势。4)自然受灾程度、劳动力水平和市场化水平对于蔬菜生产技术效率有较强的负效应,专业化水平和机械化水平对技术效率的作用不太稳定。5)蔬菜生产技术效率的演变过程可以划分为两个稳定的增长时期,2001—2003年为第一个小增长时期,2004—2013年为第二个长期稳定增长时期。

The paper based on the regional characteristic,the temporal characteristic,the planting characteristic,the industrial characteristic and the environmental characteristic of trans-log stochastic frontier production function model,using 2001-2014 panel data of China's large and medium cities,to measure the technical efficiency of vegetable production,evolution rules and factors. The results show that the technical efficiency of vegetable production increased in 14 years. Although the technical efficiency of vegetable production has significant regional differences from eastern region to western region in China,there is no obvious that the trend of regional differences comes into being Matthew Effect. Then,the technical efficiency of vegetable production also has inter-group difference and intra-group difference in different sizes of cities and different planting ways. There is a mismatch phenomenon in investment resources of vegetable production in China. Next,the capital output elasticity has falling volatility trends both in general vegetables,facilities and open field vegetables. Although the technical efficiency of facilities vegetables production is higher than that of open field vegetables,the investment factors of facilities vegetables showed the trend of diminishing returns to scale,and on the contrary,the investment factors of open field vegetables showed the trend of increased returns to scale. At the same time,the degree of natural disaster,labor productivity and marketization have strong negative effects on the technical efficiency of vegetable production,and the specialization and mechanization have unstable effects on technical efficiency. Lastly,the evolution process of vegetable technical efficiency can be divided into two stable growth periods,2001-2003 years for the first small growth period and 2004-2013 years for the second long-term stable growth period.