退耕还林的经济学理论基础:基于外在性和公共品理论的考察

The Economics Logic of the Sloping Land Conversion Program: From Externality Theory and Public Good Theory to Principal-agent Theory

本文将退耕还林工程纳入主流经济学框架中进行分析,对其经济学理论基础进行评价,并揭示其内在的经济学逻辑。首先,在外在性理论框架中讨论开征庇古税的局限性,借用科斯定理自愿的市场交易方式也难以达到退耕还林及水土保持的效果。其次,通过建立一个公共品供给博弈模型阐明了退耕还林由城市居民承担成本的原因,并借用最优税收理论阐明这一理论所导致的政策的社会成本高昂,作为一种替代机制的委托—代理成为节约社会成本的方式。最后,提出了若干政策建议。

With a huge budget, the sloping land conversion program（SLCP）has profound significance in china. We evaluate the economics theoretical basis of SLCP and reveal the internal economics logic of SLCP in a framework of mainstream economics. Firstly, we discuss the limitation of beginning to collect Pigou taxes in the framework of externality theory and point out that it is difficult to achieve good results of sloping land conversion through voluntary transaction of Coase theorem. Secondly, we illustrate the reasons of urban residents paying a price of SLCP through a game model of public goods, and by using of optimal tax theory we analyze that the policy of the theory will lead to a high social cost. As a substitution mechanism, the principalagent of SLCP is a way of cutting down the social cost. Lastly, we put forward some proposals of public policy.