长期经济增长中的公共投资政策——包含一般拥挤性公共基础设施资本存量的动态经济增长模型

Public Investment Policy in Long-run Economic Growth——General Congestion Public Infrastructure in Long-run Growth Model

本文通过建立理论模型 ,系统分析了公共基础设施资本促进长期经济增长的动力机制 ,揭示了公共投资政策与经济增长的关系。第一个模型是包含外生公共基础设施资本的动态模型。所得结果是 ,无论是纯公共性还是拥挤性的外生公共基础设施资本 ,都能够提高长期经济增长率。第二个模型是包含由公共投资形成的内生公共基础设施资本的动态模型。此模型假定公共基础设施资本由政府通过征税而进行公共投资形成 ,所得结果是 ,如果基础设施资本为纯公共性质 ,就能产生恒定的内生增长 ;如果基础设施资本为拥挤性质 ,则虽然不能产生恒定的内生增长 ,但能减缓增长率的递减 ,从而提高长期经济增长率。模型的结论表明 ,公共投资政策的研究重点不应当是政策的短期逆周期调节的效果 ,而应当是其推进长期经济增长的作用。本文的结论不仅能够解释经济增长的典型事实 ,而且可以为研究我国公共投资、积极财政、城市化战略。

Generally,infrastructure is of congestion and pure public infrastructure is an extreme example.The investment in infrastructure can be both of exogenous and endogenous.To take the general congestion into account,the paper sets up an exogenous growth model as well as an endogenous model.This paper reached the following conclusion:when the exogenous infrastructure is of pure public,it can generate long run and sustainable growth rate.And when the infrastructure is of congestion it can also increase the long run growth rate.If the endogenous infrasturcture is of pure public,it can lead to constant endogenous growth and if the infrastructure is of congestion,it can also increase the long run growth rate which varies according to the degree of congestion.