Systematical Analysis Of The Mechanism Of Small And Medium-sized Enterprises' Credit Rationing

Financing is a crucial link in the development of small and medium-sized enterprises. The characteristics of small and medium-sized enterprises have determined that the main way of their external financing is the bank credit. The financing difficulty they face mainly in the loan market is the key factor that puts a curb on the development of small and medium-sized enterprises. Therefore, it is of great importance in theory and practice to study the mechanism of small and medium-sized enterprises' credit rationing and to find the basic reason of small and medium-sized enterprises' credit rationing.The credit rationing theory, based on the general equilibrium theory, can't explain very well the economic phenomenon of Non-Walrasian Equilibrium because its assumption of symmetrical information does not match the reality. The credit rationing theory under asymmetric information, with the unique analyzing, understanding and describing to the realistic economic phenomenon accurately, can explain the essential characteristic of the phenomenon undoubtedly. But there are few papers to study the credit rationing of small and medium-sized enterprises systematically under asymmetric information. Therefore, I develop a model of the interest rate as a screening mechanism, a model of collateral as a screening mechanism and a model of obtaining information, with the assumption of asymmetric information closer to the reality, by using the methods of mathematical analysis and playing game, putting such main variables as scale of the enterprise, profit, the interest rate, risk and collateral into the frame of analyzing, and study the mechanisms of smalland medium-sized enterprises' credit rationing in theory deeply and systematically.Firstly, I develop a credit rationing model under asymmetric information, by introducing the variable of scale of the enterprise and risk variable, based on the analysis of S-W model (Stiglitz & Weiss, 1981) .1 analyze credit rationing of the interest rate as a screening mechanism under competitive market structure and monopolistic market structure, and study the dynamical effect on credit rationing of small and medium-sized enterprises when the interest rate and the market structure change. The model indicates, that the effect of favorable selection will cause smaller enterprise more likely to withdraw the loan market when bank income is certain and the interest rate rises, because smaller enterprises are relatively risky. At a certain interest rate required by banks, there is the scale effect on bank loan, and the smaller enterprises under a certain scale can't get a loan. With a increase of bank loan's cost, the critical scale will move upwards. When credit rationing is in equilibrium, the credit of smaller enterprises is rationed. If the proportion of smaller enterprises in whole enterprises is relatively large, the extent of credit rationing is large too. Whether the liberalization of the interest rate can shrink the extent of credit rationing will depend on the difference between the limited interest rate and the equilibrium interest rate under monopolistic market structure, and on the degree of asymmetric information and the degree of risk.Secondly, I develop a model of moral hazard and a model of adverse selection by introducing the variable of collaterals further. I analyze the influence of moral hazard and adverse selection on credit rationing of small and medium-sized enterprises under competitive market structure and monopolistic market structure, and the range of and the condition of the impact of collateral on credit rationing of small and medium-sized enterprises. The model of collateral as a screening mechanism shows that when credit rationing is in equilibrium, the credit of smaller enterprises is still rationed. Collateral requirement increases with decrease of the competition degree, and the extent of credit rationing increases withincrease of collateral requirement. The extent under monopolistic market structure is bigger than the extent under competitive market structure. Under certain risk condition, the collateral required by banks may become the mechanism of screening enterprise's risk types, and Spence-Mirrlees separating equilibrium will exist. If enterprise risk excesses a certain risk, Spence-Mirrlees separating equilibrium will not exist.Thirdly, I develop a model of Walrasian Equilibrium under symmetric information and a model of obtaining information separately. I study Walrasian Equilibrium under two market structures if information is symmetric, and the condition of symmetric information. The model of obtaining information focuses on how to obtain information and on the function of obtaining information based on customer relationships on credit rationing of small and medium-sized enterprises. The model of obtaining information shows that Walrasian Equilibrium under competitive market structure and monopolistic market structure will exist if the information is symmetrical between banks and enterprises. It is possible to be symmetrical information by bank's obtaining information. Whether banks will make effort to obtain information depends on the expenses of obtaining information. When the expenses exceed a certain critical expense, bank will give up efforts. The critical expense is negatively correlated with risk. Compared with under monopolistic market structure, the banks under competitive market structure will be more likely to make efforts to obtain information.Finally, the relevant conclusions drawn from the analyzing of the models are applied to the construction of Chinese loan market in transition period. Several policy suggestions have been put forward.