中国货币政策非对称效应形成机理研究

【作者】 曹永琴；

【导师】 石磊；

【作者基本信息】 复旦大学 ， 政治经济学， 2008， 博士

【摘要】 在金融市场全球化背景下,如何在不确定环境中把握好货币政策执行力度是各国中央银行在宏观调控中经常遇到的最棘手问题。为什么同样力度的政策却未能达到过去那样的调控效果?为什么等量的加息和降息对经济冲击幅度不同?为什么有的地方对货币政策“过敏”而另一些地方“迟钝”?经济学家为这些现实问题上下求索,最后将答案归结为货币政策的非对称效应。因为各地区、行业和企业在不同的经济阶段对货币政策的敏感程度存在差异,所以中央银行很难准确估计货币政策对宏观经济的影响程度,进而难以把握货币政策的调控力度。货币政策有效性随客观条件呈现有规律变化的现象称为货币政策的非对称效应。货币政策非对称效应主要表现在四个维度上。一是在时间层面上,货币政策在经济衰退期的效果强于繁荣期;二是在区域层面上,货币政策在金融发达地区的效果弱于金融欠发达地区;三是在产业层面上,货币政策对劳动密集型产业的作用效果强于资本密集型产业;四是在企业层面上,货币政策对中小型企业的影响强于大型企业。大量研究证实了货币政策在四个维度上非对称效应的存在性,但缺乏统一的理论框架分析货币政策非对称效应的形成机理。本文在新凯恩斯框架内构建菜单成本模型和金融加速器模型分析中国货币政策非对称效应形成机理。沿着货币政策传导渠道建立了不确定环境中随机动态一般均衡模型,从而能够在统一的框架内解释四个维度上货币政策非对称效应形成机理。价格粘性是货币政策非对称效应存在的前提,非对称价格传导渠道是货币政策非对称效应的直接形成机制;金融加速器在此基础上会放大货币政策非对称效应,资产负债表渠道是货币政策非对称效应的间接形成机制。本文通过构建菜单成本模型来分析价格粘性的成因,进而考察货币政策非对称效应的直接形成机制。货币政策非对称效应的主要成因是非对称的价格传导渠道,这与企业面临不确定冲击时最优定价决策密切相关。当经济受到不确定货币供给冲击时,企业通过比较菜单成本与扭曲成本决定均衡产量和价格。如果菜单成本小于扭曲成本,企业将调价不调产;又如果菜单成本大于扭曲成本,企业将调产不调价;这就是价格粘性的成因。更进一步,由于存在降价刚性,企业降价比涨价需承受更大的菜单成本。从货币政策的价格传导渠道来看,在预期通货膨胀率趋势为正的环境中,面临正向货币供给冲击时,企业更多地调整价格而非产量;面临负向货币冲击时,企业则会更多地调整产量而不是价格;这就是货币政策非对称效应的直接形成机制。如果以货币政策对产出的影响作为衡量货币政策有效性的标准,那么紧缩性货币政策比扩张性货币政策更加有效。资本品价格与投资在金融加速器作用下棘轮式互动是货币政策非对称效应间接形成机制,放大并加速了货币政策冲击对经济的非对称影响。货币政策非对称效应产生于非对称价格粘性,而放大于金融加速器,主要原因在于金融加速器会放大和加速外生扰动对整个经济系统的冲击。货币冲击经过金融加速器传导会导致外源融资升水、信贷规模和产出大幅波动,在货币政策非对称效应直接形成机制的基础上,金融加速器会放大货币冲击对产出的非对称影响。同时,金融摩擦在货币政策非对称效应的间接形成机制中发挥着核心作用。由于金融加速器机制的作用,金融摩擦与货币政策效应非对称程度之间具有非线性关系。融资杠杆与融资升水之间以及金融摩擦与金融加速数之间为正向关系,这两类正向关系决定了金融摩擦与货币政策效应非对称程度之间的正向关系。与不存在金融摩擦的信贷市场环境相比,相同程度货币政策冲击对产出的影响更大,所以正负向货币政策导致的产出变化的差距更大,这就是货币政策非对称效应的间接形成机制。金融摩擦随着具体时间、区域、产业和企业而变,由此产生的金融加速器功效差异导致货币政策非对称效应在这四个维度上表现形式和程度亦有所不同。一般而言,金融摩擦越大,金融加速器的功效越强,货币政策非对称效应越显著。在金融摩擦较大的经济环境中货币政策的实施效果比金融摩擦较小环境中的货币政策效果显著。因而,金融摩擦在不同经济阶段、区域、产业和企业间的差异使得货币政策效应在这四个维度上呈现出了非对称性。本文研究严格遵循从实践到理论再到实践的经济理论发展规律。首先,理论研究需要从实践中来。第3章在测度货币政策的基础上全面考察了货币政策对中国经济的影响,证实中国货币政策非对称效应的存在性。其次,需要依据抽象的模型工具才能透过经济现象剖析本质并寻找规律。第4章、第5章从分析市场微观主体行为入手研究货币政策非对称效应的形成机理,在新凯恩斯框架内采用随机动态一般均衡建模方法考察直接形成机制和间接形成机制在货币政策非对称效应形成中的作用,并用政策冲击试验模拟出货币政策非对称效应的价格传导机制和金融加速器传导机制。再次,实践是检验真理的唯一标准。第6章、第7章对实证结果与前两章理论仿真结果进行比照,分别从中国区域和产业层面上验证了理论模型的适用性。最后,理论应回到实践中去并形成政策指导实践。第8章列出全文主要结论并提出了相应的政策启示。本文以金融摩擦为主线,首先考察了货币政策非对称效应的价格传导机制,随后将资本品的双重属性、价格粘性形成机制、投资滞后和高昂验证成本引入了BGG框架,从资产负债表渠道入手分析货币政策冲击对经济的非对称影响。在清楚掌握货币政策非对称效应形成机理及放大机制客观规律的基础上,中央银行应该根据经济发展阶段不同调整货币政策的实施力度,根据经济周期阶段不同灵活调节货币政策力度,以及根据非对称规律实施有差别的货币政策,充分发挥货币政策结构性功能,实施部分差别化操作。更多还原

【Abstract】 With the financial market globalization, it is the most difficult thing faced on the central banks in the world that how to implement the appropriate monetary policy under the uncertain circumstances. Why the same monetary policy cannot attain the same effect like past? Why increasing and decreasing interest rate affect economy differently? Why are some regions more sensitive to monetary policy than the others? Economists have been trying their best so long to find the answer for the questions, and finally ascribe these phenomena to the asymmetric effects of monetary policy. Because the sensitive degree varies with the different regions, industries and firms, it’s difficult for the central bank to estimate the effects of the monetary policy to macroeconomy and implement desirable monetary policy.The effectiveness of monetary policy varies with external conditions, which called as asymmetric effects of monetary policy. The asymmetric effects of monetary policy show in the following four dimensions. First, the effect of monetary policy in stagnancy is stronger than that in boom; second, the effect of developed financial area is weaker than that of finance developing financial area; third, it is more sensitive for the labor intensive industry responding to the monetary policy than the capital intensive industry; and forth, the smaller firms response more stronger to monetary policy than the larger firms. Plenty of researches have testified above phenomena, but there is short of the uniform theory framework to study the mechanism of the asymmetric effects of monetary policy.This paper constructs menu cost model and financial accelerator model in the New Keynesian framework to analyze the mechanism of the asymmetric effects of monetary policy in China. Along the clue of transmission channels of monetary policy, we construct the Dynamic Stochastic General Equilibrium Model to explain the mechanism of the asymmetric effects of monetary policy in the four dimensions within a uniform framework. Sticky price is the premise of the asymmetric effect of monetary policy, and the price transmission channel is the direct mechanism of the asymmetric effect. Moreover the financial accelerator will magnify this effect further, so the balance-sheet channel is the indirect mechanism of the asymmetric effect.We analyze the causes of sticky price by way of constructing menu cost model, then study the direct mechanism of the asymmetric effect. The main cause of the asymmetric effect is the asymmetric price transmission channel, which relates closely to the firm optimum pricing confronted with the uncertain shocks. When the uncertain money shocks come, firm will decide its output and price in equilibrium by comparing menu cost with distortion cost. If menu cost is less than distortion cost, firm will adjust its price. In contrast, firm will adjust its output, which is the cause of sticky price. Further, because of the rigidity of reducing price, firm will take on more menu cost in reducing price than increasing price. From the viewpoint of the price transmission mechanism of monetary policy, under the positive trend inflation circumstance, confronting with positive money shocks firm will adjust price more often, and adjust output more often facing on negative money shocks, which is the direct mechanism of the asymmetric effects. If we measure the effectiveness of monetary policy by its effect on output, then tight monetary policy is more effective than the easy.It is the indirect mechanism of asymmetric effects of monetary policy that capital price interacts with investment under the financial accelerator, which will magnify and accelerate the asymmetric effect. The asymmetric effect roots in the asymmetric price stickiness, and is magnified by the financial accelerator. The main cause is that the financial mechanism can magnify and accelerate the shocks of external disturbance to the whole economy system. Through the financial accelerator, money shocks would induce the external financial premium, credit scale and output fluctuating strongly. Based on the direct mechanism, the financial accelerator will magnify the asymmetric effect. At the same time, the financial friction plays a pivotal role in the indirect mechanism of the asymmetric effects. Due to the financial accelerator mechanism, there is a nonlinear relationship between financial friction and the asymmetric degrees of monetary policy. There are the positive relationships between financial leverage & external financial premium and financial friction & financial accelerator, which decide the positive relationship between financial friction and the asymmetric degrees of monetary policy. Compared with the circumstance without financial friction, the same money shock affects output stronger, so the difference in output changes caused by positive and negative monetary policy becomes larger, which is the indirect mechanism of the asymmetric effect.Financial frictions vary with the different periods, regions, industries and firms, which induce effects of financial accelerator different, and ultimately the asymmetric effects behave differently in the four aspects. In general, larger is the financial friction, the more effective the financial accelerator is, and the more remarkable the asymmetric effects. The effectiveness of monetary policy with the larger financial friction is more significant than that with the smaller financial friction. Thus, the effects of monetary policy behave asymmetrically in the four aspects because of the differences of financial frictions in the different stages of business cycle, regions, industries and firms.This paper follows the rule of practice into theory into practice strictly. First, theory comes from practice. Based on the measuring the monetary policy, we study the effect of monetary policy in China, and testify the existence of asymmetric effect in 3^rd chapter. Second, only relying on the abstract model, can we know the essence hiding in the economy phenomena and find the potential laws. In the 4^th and 5^th chapters, we study the mechanism of asymmetric effects by analyzing the micro-behaviors of market participants, and use the dynamic stochastic general equilibrium model to study the roles of the direct and indirect mechanisms of the asymmetric effects, finally simulate the price and financial accelerator transmission mechanism in policy economy experiments. Third, practice is the sole criterion for testing truth. In the 6^th and 7^th chapters, we compare the empirical results with the simulation results, and testify the applicability of the theory models based on the data of regions and industries in China. Finally, the theory will come back to practice and formulate the policies to guide the practice. The 8^th chapter sums up the main conclusions in this paper and gives the policy implications.Following the financial frictions, this paper firstly study the price transmission mechanism of the asymmetric effects; then introduces the dual-functions of capital goods, price rigidity mechanism, the lagged investment and Costly State Verification into BGG model to analyze the asymmetric effects from the balance sheet channel. Based on understanding the formulating and magnifying mechanism distinctly, the central bank should adjust the monetary policy according to the different stages of economy development and business cycle, and implement protection and pressure monetary policy. Meanwhile, the central bank should exert the structural monetary policy and implement different monetary policy according to circumstances.更多还原