金融供需摩擦、信贷结构与最优财政援助政策

Financial Supply-Demand Friction,Credit Structure and Optimal Fiscal Bailout Policy

金融摩擦在金融产品定价、政府和中央银行平滑经济周期波动中发挥着至关重要的作用。然而目前还没有文献将BGG框架的企业融资需求摩擦和GK框架的银行信贷供给摩擦整合到一个框架中,对比财政政策的有效性和财政资源的战略优先配置问题。本文通过理论研究发现:(1)针对中国问题的含有金融供需摩擦的理论模型,其结果的矩吻合匹配较好,且部分指标结果优于Kirchner&Wijnbergen(2016)的框架。(2)银行信贷供给摩擦下,财政刺激效果低于无摩擦的情形;而企业融资需求摩擦下,财政刺激效果高于无摩擦的情形;对比两者,银行信贷供给摩擦下的财政政策乘数较小。(3)支持财政扩张的债务是否影响银行资产配置已成为“通过居民发债扩张”与“通过银行发债扩张”两种经济刺激的关键差别。(4)经济下行背景下,短期内财政援助银行更占优。长期内,当政府债务负担较低时,财政援助银行更占优;当政府债务负担较高时,财政援助企业更占优。

Before the 2008 financial crisis,the macroeconomic characterization of financial behavior was premised on the efficient market hypothesis.Financial factors were not systematically introduced into the macroeconomic framework.Due to the macroeconomic framework's lack of internalized financial factors,the macroeconomic impact of finance is underestimated.Also,the interaction and cross-impact mechanism between monetary policy and fiscal policy is weakened.For China,which is in the process of economic transformation,the problems in policy practice need to be analyzed and interpreted using a theoretical framework with Chinese characteristics.Based on the characteristics of financial friction,it is important to discuss the rallying point in fiscal policy,the reconstruction of fiscal functions,and the strategic priority of relocation for fiscal resources,because they are channels to improve the quality of economic development and promote economic growth.This paper analyzes the micro connection mechanism between corporate leverage and bank leverage by constructing a general equilibrium model.Furthermore,we analyze the impact of friction between financial supply and demand in theory within the framework of financial fragility in the real economy to find an optimal fiscal policy.This paper reveals that,first,the effect of fiscal stimulus is weaker under friction than under no friction in bank credit supply,and the effect of fiscal stimulus is greater under friction than under no friction in financing enterprises.Comparing the two situations,the multiplier of fiscal policy under the friction of bank credit supply is smaller.Second,under the benchmark framework of financial supply and demand friction,the major departure between“expansion through bonds issued by residents”and“expansion through bonds issued by banks”is whether the debt supporting fiscal expansion affects bank asset allocation.Third,regarding the government's optimal bailout policy,the government directly assisting banks is beneficial in the short term.Assisting banks is beneficial in the long term when the government debt burden is low.However,when the government debt burden is high,assisting enterprises is more beneficial to the economy.The welfare improvement brought about by government bailout measures is not completely independent.It also depends on the government's debt burden.This paper provides some policy implications.First,we should fully understand the existence of financial friction and how it affects the economy.Second,we should establish and improve the financial stability mechanism,regulate the loss write off in a timely manner,restructure equity and inject capital,and enhance the flexibility and stability of the central bank's balance sheet to give the self-rescuing function of financial risks full play.Third,we should pay attention to the transmission mechanism of mutual reinforcement and cross influence between local government debt risk and financial fragility.Financial institutions should enhance risk awareness,improve business philosophy,and treat the debt risk of local governments rationally and objectively.At the same time,local financial institutions should give enterprises corresponding financing support according to their own financial resources,instead of relying on government credit guarantee.This study's innovations are as follows.First,it integrates the financial frictions between enterprise financing demand and bank loan supply,and compares the effect of fiscal stimulus policy under different financial frictions.It emphasizes the financial accelerator mechanism of enterprise financing and the financial fragility of bank loan supply.Second,it expands the government debt to residents and bank holders separately,and compares the effects under the two scenarios.It discusses in detail the different fiscal stimulus effects of“expanding the government debt to residents”and“expanding the government debt to bank holders”,and compares the fundamental differences with bank credit supply friction(Kirchner and Wijnbergen,2016)in terms of mechanism.Third,we discuss whether the government should finance enterprises or banks,and compare the welfare effects under different fiscal assistance policies,in the context of economic downturn.