金融经济周期理论研究新进展

The Latest Development of Financial Business Cycle Theory

基于契约理论,金融经济周期理论在思想上继承了理性预期和货币主义学派的传统,在研究方法上借鉴了真实经济周期理论的动态一般均衡建模方法(DGEM),在周期传导机制上突破了传统周期理论。这一理论从借贷双方委托代理问题切入研究金融加速器效应,对经济短期剧烈波动进行了全新的阐释。

The financial business cycle is the persisting fluctuations and cyclical movements in economic activities caused by interior or exterior impacts, which are transmitted through financial system. The traditional economic theories claim that the origin and transmission of business cycle are irrelevant to financial factors, currencies and securities are only the virtual symbols which intermediates real economic activities, so the “financial veil view” is the core standpoint of the theories＇ system. However, the past financial crisis always came before depression. Given that the veil view deviated from economic intuitions and realities, the economists began to re-examine the role of financial factors in the business cycle. In modern financial economies, the large-scale transformation among currencies in portfolios can be fulfilled in a moment, so the transfer of international idle funds across countries is the cause and transmission mechanism of economic fluctuation. Meanwhile, lots of countries employ macro-economic policies to make economies stable. Then the economic volatilities measured by real variables become feeble, while those measured by virtual variables become significant. So the economic policies under the guidance of traditional business cycle theories cannot effectively deal with potential financial risks. Financial business cycle theories study the causes and transmission mechanism of business cycle with the modern analytical method from a brand-new angle of view, and draw the conclusions that contradict with the “view of financial neutrality” but accord with realities. The asymmetry of information is the main reason of the financial market failure, which causes the principal-agent problem between funds suppliers and users, and leads to the adverse selection and moral hazard, thus different financing channels cannot be substitutable completely. The gap in unit cost between interior funds and exterior funds is the important agency costs. The market failure is the original resource of financial friction, and agency costs are the important ingredient of the financial friction. The agency costs cyclically change with the price level in the economy. The transmission mechanism of financial business cycle is formed by the co-movement among the firm＇s net present value, financial leverage and exterior funds premium, which can be classified into “bank credit channel” and “balance sheet channel”. The special mechanism is called financial accelerator which means that the financial failure can amplify the negative impulse＇s impact on real economic activities. Now, economists have em from Prescott and Kydland to study the financial b oyed the dynamic stochastic general model usiness cycle transmission mechanism and gained fruitful achievements.