Decreasing absolute prudence: Characterization and applications to second-best risk sharing

In this paper, we provide two basic properties of utility functions u which exhibit decreasing absolute prudence i.e. (− u/u″)′ ≤ 0. These properties are used to examine the allocation of risks in an economy when some agents bear non-transferable risks. We show that it is fair Pareto-efficient to let those with a non-transferable risk bear relatively less of the transferable risk in the economy if and only if absolute prudence is decreasing. In another model, there is a complete set of contingent markets, but some agents have no direct access to them. We examine the fair efficient allocation of risk in a pool gathering a trader and a non-trader. Decreasing absolute prudence provides an upper bound to the share of the pool's risk that should be borne by the trader.     

Aggregate risk sharing and equivalent financial mechanisms in an endowment economy of incomplete participation

Summary. A pure endowment overlapping generations economy can be inefficient because of insufficient risk sharing. The introduction of an outside asset by a government or the existence of a clearing house can remedy the inefficiency by allowing some intergenerational risk sharing. While the typical outside asset is fiat money, many alternative financial mechanisms, such as social security, risk-free government bonds, mispriced deposit insurance, and income insurance can serve the same function as fiat money. Hence there are many equivalent financial mechanisms that provide intergenerational insurance. In the presence of uncertainty, there are several concepts of Pareto optimality that can be appropriately applied in an overlapping generations setting. I examine the risk-sharing arrangements associated with two different concepts of optimality, including how these arrangements are financed. The results are related to, and in some instances an extension of, the equivalence results obtained by Chamley and Polemarcharkis (1984), Weiss (1977), and Wallace (1981).Received: 4 March 2003, Revised: 30 January 2004JEL Classification Numbers: E40, E44, D51.P. Labadie: I would like to thank the participants of the Economic Theory Symposium Recent Developments in Money and Finance at Purdue University, May 2-4, 2003 and an anonymous referee for comments on this version. I am grateful to Bruce Smith for comments on an earlier version.     

Why don't we observe improvements in consumption smoothing as countries get more financially integrated: Bridging theory and empirics

This study provides suggestive theoretical and empirical evidence that the productivity shock correlation between a country and the rest of the world may help explain why we do not observe more consumption smoothing as countries have become more financially liberalized.     

The design of a consumption tax under capital risk

This paper focuses on the design of a consumption tax in a world of capital risk. The certainty literature discusses two standard options, namely the cash flow method and the pre-payment method (i.e., the wage tax), and finds the two approaches to be equivalent. Models that consider capital risk (via asset choice) reach different conclusions. This discrepancy arises in part due to a different choice of the social discount rate. In light of the failure of the discount-rate argument to resolve the issue at hand, we explore the market certainty equivalence of risky government revenue. We let revenue risks stay in the private sector, and examine the market value of the feasible transfer (e.g., in the form of a public good) back to households. We reach three broad conclusions. First, we find that if the state returns to each household its own tax-revenue risks, equivalence will be re-established as in certainty models. Next, we show that if the state engages in intergenerational risk sharing (e.g., through a system of stochastic tax transfers), the wage tax cannot be construed to be a valid pre-payment alternative to the cash flow or a modified wage-tax-ation system. Efficient risk allocation across generations under a cash flow tax (or, one that includes future capital gains as well as wages in the tax base) leads to a Pareto improvement over the simple wage tax. Finally, a major policy implication follows; in order to be practicable, a consumption tax would have to be implemented via registered savings accounts much in the fashion of the Canadian registered retirement savings plans program rather than through the pre-payment route.     

Segmented risk sharing in a continuous-time setting

Summary. The economy we study is comprised of a continuum of individuals. Each has a stochastic endowment that evolves continuously and independently of all other individuals' endowment processes. Individuals are risk averse and would therefore like to insure their endowment processes. The mutual independence of their endowment processes makes it feasible for them to obtain this insurance by pooling their endowments. We investigate whether such a scheme would survive as an equilibrium in a noncooperative setting. Received: October 16, 2000; revised version: August 8, 2001     

Linking global economic dynamics to a South African-specific credit risk correlation model

In order to address practical questions in credit portfolio management it is necessary to link the cyclical or systematic components of firm credit risk with the firm's own idiosyncratic credit risk as well as the systematic credit risk component of every other exposure in the portfolio. This paper builds on the methodology proposed by Pesaran, Schuermann, and Weiner [Pesaran, M.H., Schuermann, T., and Weiner, S.M., (2004), Modeling regional interdependencies using a global error correcting macroeconometric model, Journal of Business and Economic Statistics, 22, 2, 129–169.] and supplemented by Pesaran, Schuermann, Treutler and Weiner [Pesaran, M.H., Schuermann, T., Treutler, B., and Weiner, S.M., (2006), Macroeconomic dynamics and credit risk: a global perspective, Journal of Money, Credit, and Banking, Volume 38, Number 5, August 2006, 1211–1261.] which has made a significant advance in credit risk modelling in that it avoids the use of proprietary balance sheet and distance-to-default data, focusing on credit ratings which are more freely available.In this paper a country-specific macroeconometric risk-driver engine which is compatible with and could feed into the GVAR model and framework of PSW (2004) is constructed, using vector error-correcting (VECM) techniques. This allows conditional loss estimation of a South African-specific credit portfolio but also opens the door for credit portfolio modelling on a global scale, as such a model can easily be linked to the GVAR model. The set of domestic factors is extended beyond those used in PSW (2004) in such a way that the risk-driver model is applicable for both retail and corporate credit risk. As such, the model can be applied to a total bank balance sheet, incorporating the correlation and diversification between both retail and corporate credit exposures.Assuming statistical over-identification restrictions, the results indicate that it is possible to construct a South African component for the GVAR model that can easily be integrated into the global component. From a practical application perspective the framework and model is particularly appealing since it can be used as a theoretically consistent correlation model within a South African-specific credit portfolio management tool.     

Securitization,collateral constraints and consumption risk sharing in the euro area

Scarcity of housing collateral is associated with lower credit volumes and hence decreases consumption risk sharing among seven euro area countries in the time period from 1987Q1 to 2007Q4. At the same time, securitization improves risk sharing but does not seem to outweigh the collateral scarcity effect.     

The Empirical Analysis on the Influence of Foreign Exchange Reserves on China＇ s Price Level --Based on the Cointegration Test and the Error Correction Model analysis

协整和格兰杰因果检验结果表明,我国外汇储备与物价水平存在协整关系,且外汇储备是物价水平的格兰杰原因,表明外汇储备增加将对通货膨胀形成压力。但从误差修正模型的检验结果看,我国外汇储备对物价水平的影响在短期内较为有限,其主要原因是我国央行短期内进行大量的外汇冲销操作。因此,我国需要采取有效的措施来缓解通胀压力,如加大央行公开市场业务操作、改革外汇管理体制、适当放宽汇率浮动幅度以及合理使用我国现有外汇储备等。     

Aggregate fluctuations, financial constraints and risk sharing

Summary. Private information and costly state verification often result in credit rationing in models with smooth investment, affecting both loan size and total investment. The optimal contract is derived in a dynamic stochastic growth model with capital for two types of models: one with symmetric information and the other with asymmetric information and costly state verification. When all information is observed costlessly, the equilibrium optimal contract provides complete insurance to risk-averse savers against aggregate fluctuations. When information is asymmetric and there is costly state verification, the equilibrium optimal contract provides only partial insurance against aggregate shocks. The extent of insurance is measured by the marginal rate of transformation of consumption between borrowers and lenders which is closely linked to the user cost of capital. The deadweight monitoring costs create a wedge between a borrower's cost of capital and a lender's stochastic discount factor, with two results: (i) fluctuations in the user cost of capital provides a mechanism by which aggregate shocks can be␣propagated; (ii) the distribution of capital's share of output among borrowers, lenders, and monitoring costs varies even if capital's share is constant. Capital market frictions not only amplify aggregate fluctuations but also generate cross-sectional fluctuations that may not be observable in aggregate data. Received: November 17, 1997; revised version: April 20, 1998     

人民币实际汇率波动对中美贸易收支的影响——基于1990—2009年时间序列分析

基于协整理论、误差修正模型和格兰杰因果检验并根据中国和美国1990-2009年的季度数据,分析人民币实际汇率变动对中美贸易收支的影响.结果表明:影响中美贸易收支的主要因素包括美国的实际GDP、中国的实际GDP和人民币实际汇率,且三者的影响力次第减弱,中美贸易也存在明显的J曲线效应.因此,改善中美贸易失衡应扩大中国内需、调整业口结构和改革人民币汇率制度.     

Aggregation of heterogenous beliefs,asset pricing,and risk sharing in complete financial markets

Given a competitive equilibrium in complete asset markets, we propose a method that aggregates heterogeneous individual beliefs into a single “market probability,” which, if commonly shared by investors, generates the same marginal valuation of assets by the market as well as by each individual investor. As a result of the aggregation process, the market portfolio may have to be scalarly adjusted, upward or downward, a reflection of an aggregation bias due to the diversity of beliefs. From a dual viewpoint, the standard construction of an expected utility-maximizing aggregate investor designed to represent the economy in equilibrium, is shown to be also valid in the case of heterogeneous beliefs, modulo the above scalar adjustment of the market portfolio, thereby generating an Adjusted version of the Consumption based Capital Asset Pricing Model (ACCAPM). We analyze how the allocation of aggregate and individual risks relates to deviations of individual beliefs from the aggregate market probability. Finally, we identify the channels through which the distribution of beliefs and other microeconomic characteristics (incomes, attitudes toward risk) across investors impact the pricing of risky assets an may contribute to explaining the equity premium puzzle.     

Monetary policy in Germany: A cointegration analysis on the relevance of interest rate rules

The paper attempts to identify an empirical relationship that characterizes the way the Bundesbank adjusted its short-term rate with respect to various objectives. By building on a careful exploration of the properties of the variables involved, it is established that interest rate rules —often remarkably similar to the Taylor rule— remain valid and relevant in a Vector Error Correction framework, and thereby proposing a distinctive interpretation of German monetary policy during the period 1975–1998.     

区域外部性、对外开放与中国经济增长条件收敛

区域经济增长差异是经济发展过程中所出现的必然现象。空间自相关和回归分析方法的运用使我们可以就空间外溢对区域经济增长以及地理分布进行有效的分析。本文在新古典增长模型的基础上,提出了经济增长β收敛的空间计量经济分析模型框架,采用1978-2005年的截面数据,分析了空间外部性和对外开放对β收敛的影响。研究发现我国自改革开放以来区域经济增长不存在显著的绝对收敛。考虑空间外部性和对外开放因素后,可以观察到明显的经济增长条件收敛现象。     

我国地区经济差距与投资差距的实证分析

本文通过泰尔指数将地区经济差距和投资差距量化,并对两者之间的变动趋势进行了分析研究.结果表明,地区投资分布的不均衡程度大于地区经济的不均衡,而且我国地区经济差距与投资差距在20世纪80年代到90年代中后期具有极为相似的变动趋势,到90年代后期则出现背离.其主要原因在于,技术、人力资本等带来的投资效率提高对我国地区经济增长的作用越来越大,地区经济差距是投资数量与效率的地区差距综合作用的结果.     

Sovereign risk and deposit dynamics: evidence from Europe

The unprecedented expansion of sovereign balance sheets since the beginning of the global crisis has given a new meaning to the term sovereign risk. Developments in Europe since early 2010 revealed new challenges for the functioning of private banks in an environment of heightened sovereign risk and may have contributed to deleveraging. The article uses an innovative way of measuring the perception of sovereign risk and its impact. Using an extension of a common market discipline framework, it shows that exposure to sovereign risk may have limited the ability of banks in Europe to collect deposits. Potential identification issues between deposits and bank efficiency are controlled by using data envelopment analysis (DEA). The results are robust to inclusion of conventional measures of bank performance and the sector-wide holdings of foreign sovereign debt.     

转型期中国农户消费--收入的长期均衡与短期动态关系

文章在通过对中国农户消费--收入关系进行协整检验的基础上,建立两个变量的误差修正模型,进行Granger因果关系检验,对中国农户消费--收入的关系进行实证分析,希望能为分析中国农户消费的行为特点和刺激农户消费的政策选择提供实证依据.     

Heterogeneity,saving-investment dynamics and capital mobility in Latin America

The purpose of this paper is to analyze the dynamics of national saving-investment relationship in order to determine the degree of capital mobility in 12 Latin American countries. The analytically relevant correlation is the short-term one, defined as that between changes in saving and investment. Of special interest is the speed at which variables return to the long run equilibrium relationship, which is interpreted as being negatively related to the degree of capital mobility. The long run correlation, in turn, captures the coefficient implied by the solvency constraint. We find that heterogeneity and cross-section dependence completely change the estimation of the long run coefficient. Besides we obtain a more precise short run coefficient estimate compared to the existent estimates in the literature. There is evidence of an intermediate degree of capital mobility, and the coefficients are extremely stable over time.      

中国的区域关联与经济增长的空间溢出效应

本文使用探索性空间数据分析工具研究了1988-2009年间中国各省区人均GDP的空间分布格局与特征,结果显示:一方面,存在着全域范围的正的空间自相关性,并且这种相关性随着时间的推移在增大;另一方面,局域相关也显示出中国局域性的空间集聚特征越来越明显。以一个表征市场潜能对地区经济发展影响的新经济地理学模型为基础,本文通过计量分析进一步考察了中国区域经济发展的空间溢出效应。经验分析表明,空间溢出效应是中国地区经济发展不可忽视的重要影响因素,市场潜能每增长1%,地区人均GDP增长率将提高0.47%,超过了地区固定资产投资增长的弹性值。当然,实证分析也发现这种空间溢出效应会随着地区间距离间隔的增加而减少。     

中国区域要素替代弹性变迁及其增长效应——基于异质劳动视角的随机前沿生产函数分析

文章采用1996-2014年省际面板数据构建区域随机前沿生产函数模型,从劳动异质性视角拓展要素替代弹性分析;并首次联合运用协整方程和误差修正模型,从长期均衡和短期波动过程分析来揭示要素替代约束对经济增长的影响.结果发现:尽管三大区域各自的要素替代弹性变化显著不同,但要素替代弹性的增长效应却彼此具有一致性.其中,东部地区的资本-劳动替代弹性明显地存在着0.805的增长门槛,只有西部地区的资本-劳动替代弹性越过了门槛值,与区域增长具有尚不显著的正相关性而支持德拉格兰德维尔假说;三大区域的资本-技能互补性提高对经济增长的推动作用都不明显;劳动-技能替代弹性则表现为显著的正向增长效应,显示出各区域存在着人力资本红利.值得注意的是,与均衡增长路径上"资本-劳动替代弹性提高能够推动经济增长"的德拉格兰德维尔假说不同,在考虑劳动异质性和技术非效率的前提下,中国地区增长更支持"劳动-技能替代弹性提高能够推动经济增长"的结论.文章为甄别新常态下的区域增长潜力转变、剖析要素匹配合理性及产业结构调整可行性奠定基础.     

中国农村消费行为及其制约因素分析

农民收入水平低、消费不力一直是制约我国经济增长的大问题。研究表明:收入与消费倾向负相关,且持久收入弹性小于暂时收入弹性,利率与消费倾向显著正相关,这暗示:由于对未来的支出存在悲观预期,农民更注重将持久性收入列入储蓄计划,而将利息收入、外出务工收入等额外的暂时性收入用于改善生活。农业投入不足是农村消费市场疲软的最根本原因。价格对农民消费行为的影响具有滞后性。因此,启动内需,关键在于改善农村消费环境,拓宽就业渠道,减轻农民负担。