资本账户开放与国际金融冲击的传导——基于DSGE模型的分析

本文在动态随机一般均衡的框架下,建立了一个包括贸易部门和非贸易部门的小型开放经济模型,系统研究和比较资本管制与资本账户开放两种情况下,国外金融冲击、出口需求冲击对中国经济的不同影响和传导机制,并检验资本账户开放情形下应对国际冲击时不同货币政策规则的有效性。结果发现：当资本账户开放时,一国受到国外冲击的波动幅度远大于资本管制的情况;资本管制和资本账户开放对国际金融冲击传导机制的关键差异在于贸易部门与非贸易部门的互动关系,具体表现为劳动力转移的差异;在资本账户开放后,面对不同形式的国际冲击,货币数量型规则和混合型规则均能有效熨平经济波动。     

Financial frictions,interest rate dynamics,and international business cycle synchronization

A two‐country real business cycle model with national endogenous borrowing constraints and working capital requirements can account for the high level of international co‐movements. The effects of technology shocks are transmitted internationally through the dynamics of the interest rate. Specifically, the borrowing mechanism brings about a wedge between the real interest rate and the expected marginal product of capital, such that interest rates fall following positive technology shocks. A lower interest rate induces more investment by Foreign firms, which in turn contribute to greater synchronization of economic activities across countries. Moreover, terms of trade amplify the effects of technology shocks.     

Effects of uncertain lifetime and annuity insurance on capital accumulation and growth

Summary.  This paper studies the effects of uncertain lifetime on capital accumulation and growth and also the sensitivity of those effects to the existence of a perfect annuities market. The model is an overlapping generations model with uncertain lifetimes. The technology is convex and such that the marginal product of capital is bounded away from zero. A contribution of this paper is to show that the existence of accidental bequests may lead the economy to an equilibrium that exhibits asymptotic growth, which is impossible in an economy with a perfect annuities market or with certain lifetimes. This paper also shows that if individuals face a positive probability of surviving in every period, they may be willing to save at any age. This effect of uncertain lifetime on savings may also lead the economy to an equilibrium exhibiting asymptotic growth even if there exists a perfect annuities market. Received: April 17, 1996; revised version: December 9, 1997     

Trade integration and risk sharing

What are the effects of increased trade in goods and services on the trade balance? We study the effects of reducing transport costs in a Ricardian model with complete asset markets and find that this increases the volatility of the trade balance. This result applies regardless of whether supply or demand shocks are the main source of economic fluctuations. Both type of shocks generate fluctuations in the trade balance that are in part moderated by stabilizing movements in the terms of trade. Trade integration dampens these terms of trade movements and, for a given distribution of shocks, amplifies fluctuations in the trade balance. To overturn this result, one must assume that either trade integration is sufficiently biased towards goods with strong comparative advantage and/or risk aversion is sufficiently extreme. We calibrate the model to U.S. data and find that, for reasonable parameter values, increased trade in services could double the volatility of the trade balance.     

Oil Prices, Terms of Trade Shocks, and Macroeconomic Fluctuations in Saudi Arabia

The article investigates the sources of macroeconomic fluctuations in Saudi Arabia using structural vector autoregression methods and pays particular attention to oil prices and changes in terms of trade. Using a macroeconomic model tailored to the Saudi Arabian economy, the authors identify terms of trade, supply, balance of payments, aggregate demand, and monetary shocks. The results show that the Saudi Arabian price level, real exchange rate, and to a lesser extent output is vulnerable to terms of trade shocks. Moreover, Saudi Arabian terms of trade are driven by output, trade balance, and aggregate demand shocks. To stabilize output and the real exchange rate, Saudi Arabia ought to continue diversifying its production base and aim for a stable nominal oil price. (JEL E32 , Q43 , C22 )     

Understanding the Effect of Productivity Changes on International Relative Prices: The Role of News Shocks

The US real exchange rate and terms of trade have been found to appreciate when US labour productivity increases relative to the rest of the world. This finding is at odds with predictions from standard international macroeconomic models. In this paper, we find that incorporating news shocks to total factor productivity (TFP) in an otherwise standard open‐economy sticky‐price dynamic stochastic general equilibrium (DSGE) model with variable capital utilization can help the model replicate the above empirical finding. Labour productivity increases in our model after a positive news shock to TFP because of an increase in capital utilization. Under some plausible calibrations, the wealth effect of good news about future productivity can increase domestic demand strongly and induce an increase in home goods prices relative to foreign goods prices.     

Monetary policy and commodity terms of trade shocks in emerging market economies

Commodity terms of trade shocks have continued to drive macroeconomic fluctuations in most emerging market economies. The volatility and persistence of these shocks have posed great challenges for monetary policy. This study employs a New Keynesian Dynamic Stochastic General Equilibrium (DSGE) model to evaluate the optimal monetary policy responses to commodity terms of trade shocks in commodity dependent emerging market economies. The model is calibrated to the South African economy. The study shows that CPI inflation targeting performs relatively better than exchange rate targeting and non-traded inflation targeting both in terms of reducing macroeconomic volatility and reducing the losses of a non-benevolent central bank. However, macroeconomic stabilisation comes at a cost of increased exchange rate volatility. The results suggest that the appropriate response to commodity induced exogenous shocks is to target CPI inflation.     

Flexible exchange rates as shock absorbers

In this paper we analyze empirically the effect of terms of trade shocks on economic performance under alternative exchange rate regimes. We are particularly interested in investigating whether terms of trade disturbances have a smaller effect on growth in countries with a flexible exchange rate arrangement. We also analyze whether negative and positive terms of trade shocks have asymmetric effects on growth, and whether the magnitude of these asymmetries depends on the exchange rate regime. We find evidence suggesting that terms of trade shocks get amplified in countries that have more rigid exchange rate regimes. We also find evidence of an asymmetric response to terms of trade shocks: the output response is larger for negative than for positive shocks. Finally, we find evidence supporting the view that, after controlling for other factors, countries with more flexible exchange rate regimes grow faster than countries with fixed exchange rates.     

HOW IMPORTANT ARE TERMS‐OF‐TRADE SHOCKS?

According to conventional wisdom, terms‐of‐trade shocks represent a major source of business cycles in emerging and poor countries. This view is largely based on the analysis of calibrated business‐cycle models. We argue that the view that emerges from empirical structural vector autoregression (SVAR) models is strikingly different. We estimate country‐specific SVARs using data from 38 countries and find that terms‐of‐trade shocks explain less than 10% of movements in aggregate activity. We then estimate key structural parameters of a three‐sector business‐cycle model country by country and find a disconnect between the importance assigned to terms‐of‐trade shocks by theoretical and SVAR models.     

International Risk Sharing and the Transmission of Productivity Shocks

This paper shows that standard international business cycle models can be reconciled with the empirical evidence on the lack of consumption risk sharing. First, we show analytically that with incomplete asset markets productivity disturbances can have large uninsurable effects on wealth, depending on the value of the trade elasticity and shock persistence. Second, we investigate these findings quantitatively in a model calibrated to the U.S. economy. With the low trade elasticity estimated via a method of moments procedure, the consumption risk of productivity shocks is magnified by high terms of trade and real exchange rate (RER) volatility. Strong wealth effects in response to shocks raise the demand for domestic goods above supply, crowding out external demand and appreciating the terms of trade and the RER. Building upon the literature on incomplete markets, we then show that similar results are obtained when productivity shocks are nearly permanent, provided the trade elasticity is set equal to the high values consistent with micro-estimates. Under both approaches the model accounts for the low and negative correlation between the RER and relative (domestic to foreign) consumption in the data—the "Backus–Smith puzzle".     

Do news shocks increase capital utilization?

Using the workweek of capital as a measure of capital utilization, we empirically test whether news shocks actually increase capital utilization. To this end, by estimating a panel VAR on two-digit manufacturing data identifying news shocks as innovations to stock returns orthogonal to the variations in current-period TFP growth, we find the positive response of capital utilization to news shocks. Moreover, to explain the positive response of capital utilization to news shocks in terms of plant-level investment behavior, we propose a heterogeneous plant model that combines the fixed cost of capital adjustment and an endogenous capital utilization choice. With the presence of fixed costs, except for the plants that have recently adjusted capital stock, news shock shortens the effective time horizon of currently installed capital stock and increases capital utilization. When the model economy is calibrated to match the salient features of the plant-level investment rate distribution, the economy generates a news-driven positive response of capital utilization.     

INTERNATIONAL TRADE AND REGIONAL DEVELOPMENT

The paper considers a two-region model of trade based on the authors'earlier (HS) model, in which two nontraded goods, one urban and one rural, were introduced into the Harris-Todaro model. The HS framework captures the duality of the labour market, and it is argued that the HS model is suited to the purpose of regional analysis where the urban and rural agents may be in conflict as their welfare (income) may not respond in an identical manner to exogenous shocks and policy changes. The paper examines the implications of a change in capital and the terms of trade on outputs and regional incomes. It is established that in response to a terms-of-trade shock the prices of urban and rural nontraded goods could move in opposite directions, so structural change could also be in opposite directions. The same could also be true of welfare in the two regions.     

Imperfect Competition, Capital Shortages and Unemployment Persistence

We construct a model integrating the traditions of imperfect competition macroeconomics and real business cycles. For this we study a dynamic economy with optimizing households, firms and trade unions subject to stochastic shocks. We can derive closed form solutions for the behaviour of all agents. It is found that the combination of capital shortages and imperfect competition in labor markets can give rise to unemployment, and that this unemployment is quite persistent, even when the underlying shocks are not.     

Inflation in Open Economies with Complete Markets

This paper uses an overlapping generations model to analyze monetary policy in a two-country model with asymmetric shocks. Agents insure against risk through the exchange of a complete set of real securities. Each central bank is able to commit to the contingent monetary policy rule that maximizes domestic welfare. In an attempt to improve their country’s terms of trade of securities, central banks choose to commit to costly inflation in favorable states of nature. In equilibrium the effects on the terms of trade wash out, leaving both countries worse off. Countries facing asymmetric shocks may therefore gain from monetary cooperation.     

Output stabilization in fixed and floating regimes: Does trade of new products matter?

This paper studies the dynamics of output and export margins in the aftermath of global shocks in fixed and floating exchange rate regimes. Using a panel vector autoregressive model with exogenous factors, it traces the mean responses of output, terms of trade, extensive and intensive margins to real and nominal shocks in 22 developed economies over the period 1988–2011. We find remarkable differences in the transmission of shocks across exchange rate regimes. Adjustment takes place mainly at the extensive margin in fixed regimes, and implies a crowding out of intensive margins that is not present among floaters. Large movements at the extensive margin are associated with a weaker performance in terms of output stabilization. Our findings are robust to alternative sample selections and identification of the shocks. The evidence in the paper stresses a novel advantage of flexible exchange rates based on their ability to smooth the fluctuations in trade of new products.     

What Determines Real Exchange Rates? The Nordic Countries

The model derived in this paper yields testable implications concerning the long‐run co‐movements of real exchange rates, relative labor productivity, the trade balance and terms of trade. Countries with relatively higher output growth, trade deficits or improved terms of trade are found to have more appreciated real exchange rates, with the main channel of transmission working through the relative price of nontraded goods. Exogenous terms‐of‐trade shocks are found to be the most important determinant of long‐run movements in the real exchange rate for Denmark and Norway, while demand shocks account for most of the long‐run variance in the real exchange rate for Finland and Sweden.     

International risk sharing and commodity prices

Abstract Cole and Obstfeld (1991) exposited a classic result where equilibrium movements in the terms of trade could make ex ante risk‐sharing arrangements unnecessary: a unity elasticity of substitution across goods and production specialization. This paper extends their model to N countries and M commodities (N > M). Here the terms of trade provides insurance against commodity‐specific shocks, not country‐specific shocks. Using commodity‐level production data at the national level and world commodity prices, we document significant terms of trade variability and positive responses of nation‐specific production to terms of trade improvements. The endogenous terms of trade insurance mechanism highlighted in CO is virtually non‐existent.     

通胀目标制与汇率目标制不能共存吗

基于汇率传递的风险溢价渠道，本文将我国利率调控通胀、外汇储备对冲干预汇率纳入新凯恩斯政策模型，构建双目标双工具政策分析框架，比较泰勒规则与双目标双工具规则下通胀目标与汇率目标共存的经济机制与效应。本文模拟显示：（1）双目标双工具政策框架下通胀目标与汇率目标能够共存，此时通过影响汇率风险溢价来盯住汇率不影响通胀；而单工具政策下两目标无法共存，此时降低国内资产的收益率盯住汇率会刺激居民的消费行为引起通胀。（2）国际资本冲击下，双目标双工具政策在固定汇率的同时能保证经济稳定；而当贸易条件恶化时，选择完全浮动汇率制度最优。央行政策损失分析进一步验证了以上结论。（3）随着金融市场化改革深入，外汇储备稳定汇率的有效性将下降，冲销成本会大幅提升。资本账户开放下，双目标双工具政策仍是央行抵御外部资本冲击的首选政策；但是汇率市场化后，通胀目标制与双目标双工具政策效果基本无差异。本文结论的启示是：面对国际资本，需必要的汇率管制；但是面对贸易冲击，可适度提升汇率弹性来减少冲击对产出和通胀的影响。     

Real exchange rates,asset prices and terms of trade: A theoretical analysis

This paper develops a continuous-time two-country dynamic equilibrium model, in which the real exchange rates, asset prices, and terms of trade are jointly determined in the presence of nontradable goods. The model determines the relation between the financial markets and real goods markets in the world economy and their responses to various shocks under the home bias assumption. A positive domestic supply shock induces a positive return on the domestic asset markets and a deterioration of terms of trade that improves the foreign output and boosts the foreign asset markets. Demand shocks act in the opposite way. This model also analyses the impact of change in the relative price of nontradable to tradable goods on the terms of trade and asset markets. A higher productivity growth in tradable goods than in nontradable goods leads to a higher relative price of nontradable to tradable goods, which appreciates the real exchange rate, deteriorates the terms of trade, and depresses the domestic and foreign asset markets. A lower relative price of nontradable goods depreciates the real exchange rate, improves the terms of trade, and lifts both the domestic and foreign asset markets.     

A welfare analysis of social security in a dynastic framework*

In this article, we study the welfare effects of unfunded social security in a general equilibrium model populated with overlapping generations of altruistic individuals that differ in lifetime expectancy and earnings ability. Contrary to previous research, our results indicate that steady‐state welfare increases with social security for most households, although by very different amounts. This result is mainly due to two factors. First, the presence of two‐sided altruism significantly mitigates the crowding out effect of unfunded social security. Second, ability shocks and uncertain lifetimes generate significant heterogeneity among households to yield different induced preferences for social security.