预算软约束、融资溢价与杠杆率--供给侧结构性改革的微观机理与经济效应研究

Soft Budget Constraint,Financing Premium and Leverage:Micro-mechanism and Economic Effects of the Supply-side Structural Reform

本文针对我国部分企业中存在的预算软约束问题及其造成价格扭曲、资源错配的现实背景,在金融加速器理论的基础上,首先建立嵌入预算软约束的金融加速器机制,通过企业与金融机构债务契约优化问题,得到预算软约束企业的融资溢价方程,阐述预算软约束造成价格扭曲及资源错配的内生机理。然后构建动态随机一般均衡模型,阐释供给侧结构性改革"三去一降一补"五大任务对经济变量的具体影响,并通过参数调整揭示供给侧结构性改革削弱预算软约束,增强宏观调控政策有效性以及促进长期经济增长的微观机理和经济效应,进而为推进供给侧结构性改革和经济长期可持续发展提供理论依据和政策建议。

Summary： Under the economic New Normal, China has put forward the supply-side structural reform, which consists of five tasks including cutting overcapacity, destocking, deleveraging, reducing costs, and improving weak links. However, price distortion still occurs and may cause curing of the allocation structure, negative market players, and inefficient economic operation. Therefore, it is of great significance to study how to eliminate price distortion and optimize resource allocation to effectively promote supply-side structural reform and the long-term development of China＇s economy. This paper builds a financial accelerator mechanism embedded with a soft budget constraint based on the theory of Bernanke et al. （1999） , and explains the endogeneity of financing price distortion and resource misallocation caused by soft budget constraint. Then, we construct a DSGE model to explore the micro-mechanism and effects of the reform. The innovation of this paper is mainly based on two aspects. It establishes a financial accelerator mechanism embedded with the soft budget constraint and makes price distortion endogenous. We derive the financing premium equation for soft- budget-constraint enterprises from the debt contract optimization problem between enterprises and financial institutions. It illustrates that the soft budget constraint can weaken the relevance of the finance premium on the leverage ratio and thus cause price distortion and resource misallocation. In addition, a DSGE model is constructed to describe the specific effect of the reform. Based on the soft budget constraint mechanism, the DSGE model describes six economic subjects, including the soft-budget-constraint enterprise and the budget-constraint enterprise. The micro effects of the five tasks 6f the reform can be qualified by the model parameters; therefore, it is possible to explore the outputs of the two enterprises and the overall economy in different reform scenarios with the model. The results of the study are as follows. First, the problem of the soft budget constraint in some enterprises results in price distortion and resource misallocation. Due to the guarantee from the government, the financing price of soft-budget- constraint enterprises is relatively lower and cannot fully reflect the loan cost and risk premium. Thus, the soft-budget- constraint enterprise can borrow more capital at a lower price, which may lead to a higher leverage ratio and hinder the market from clearing. Second, the supply-side structural reform can boost the sensitivity of output to the shocks of interest rate, government spending, and technology by weakening the soft budget constraint, thereby enhancing the effectiveness of macro-control policies. Specifically, cutting overcapacity and destocking can reduce the proportion of soft-budget-constraint enterprises in the whole economy. Deleveraging can reduce the degree of loan guarantee of the enterprise. Reducing costs and improving weak links may improve the total factor productivity of enterprises, especially soft-budget-constraint enterprises. Our model shows that due to the limited resources and the crowding-out effect between these two enterprises, the reform can weaken the negative effects of the soft budget constraint and improve the effectiveness of monetary policy and fiscal policy. Third, the reform can significantly improve China＇s long-term growth trend. It is shown that by weakening the influences of the soft budget constraint and improving the total factor productivity of enterprises, the five tasks of the supply- side structural reform can promote China＇s steady economic growth for the next 20 years. Based on these results, we propose that to promote the supply-side structural reform, first it is necessary to clear excess capacity and improve capital efficiency, strengthen the budget constraint and eliminate price distortion, and deepen financial reform and optimize resource allocation.