Risk aversion, moral hazard, and the principal's loss

Summary. In their seminal paper on the principal-agent model with moral hazard, Grossman and Hart (1983) show that if the agent's utility function is , then the loss to the principal from being unable to observe the agent's action is increasing in the agent's degree of absolute risk aversion. Their proof is restricted to the case where the number of observable outcomes is equal to two, and it uses an argument that is specific to that case. In this note, we provide an alternative proof that generalizes their result to any (finite) number of outcomes. Received: March 21, 2001; revised version: June 21, 2001     

Conflicting tasks and moral hazard: Theory and experimental evidence

We study a multi-task principal-agent problem in which tasks can be in direct conflict with each other. In theory, it is difficult to induce a single agent to exert efforts in two conflicting tasks, because effort in one task decreases the success probability of the other task. We have conducted an experiment in which we find strong support for the relevance of this incentive problem. In the presence of conflict, subjects choose two efforts significantly less often when both tasks are assigned to a single agent than when there are two agents each in charge of one task.     

Occupational self-selection in a labor market with moral hazard

This paper studies the determinants and implications of self-selection when firms imperfectly observe worker effort. The effects of the resulting moral hazard problem on the self-selection mechanism are analyzed in a model in which workers simultaneously choose an employment sector and an effort level. The implications of the model reveal that in the presence of moral hazard, workers’ effort decisions become an additional mechanism determining the pattern of selection into sectors. Workers’ sector-specific endowments impact sectoral allocation through their effect on workers’ comparative advantage as well as their effect on workers’ shirking propensity. The model is then used in an empirical application that analyzes workers’ self-selection into white collar and blue collar occupations. The estimation results, based on data from the National Longitudinal Survey of Youth, suggest that workers’ occupational self-selection leads to higher wages and lower dismissal rates in both occupations, compared to an economy in which workers are randomly assigned to each occupation. The difference in dismissal rates between the two occupations is driven by the higher expected productivity in the white collar sector. The positive effects of occupational sorting diminish as the labor market becomes increasingly characterized by moral hazard. Results also suggest that human capital investments in skills that are most relevant to blue collar jobs may generate higher wages and lower dismissal rates in both white collar and blue collar occupations.     

General equilibrium with endogenous securities and moral hazard

Summary. This paper studies a class of general equilibrium economies in which the individuals endowments depend on privately observed effort choices and the financial markets are endogenous. The environment is modeled as a two-stage game. Individuals first make strategic financial-innovation decisions. They then act in a Radner-type economy with the previously designed securities. Consumption goods, portfolios, and effort levels are chosen competitively (i.e., taking prices as given). An equilibrium concept is adapted for these moral hazard economies and its existence is proven. It is shown through an example how incentive motives might lead to the endogenous emergence of financial incompleteness.Received: 18 March 2002, Revised: 16 February 2004, JEL Classification Numbers: D52, D82, G10, G22.This paper is based on an essay from my Ph.D. dissertation at the University of Chicago. I am thankful for comments from Fernando Alvarez, Rodrigo Cerda, Pierre-André Chiappori, Rubens P. Cysne, Carlos E. da Costa, Milton Harris, Lars Stole, Juan P. Torres-Martínez, Paulo K. Monteiro, Philip Reny, Iván Werning, an anonymous referee, and seminar participants at the 6th SAET Conference and the 22th SBE Meeting. Financial support from CNPq is gratefully acknowledged.     

Screening risk-averse agents under moral hazard: single-crossing and the CARA case

Principal-agent models of moral hazard have been developed under the assumption that the principal knows the agent's risk-aversion. This paper extends the moral hazard model to the case when the agent's risk-aversion is his private information, so that the model also exhibits adverse selection. We characterize the optimal menu of contracts; while its detailed properties depend on the setting, we show that some of them must hold for all environments. In particular, the power of incentives always decreases with risk-aversion. We also characterize the relationship between the outside option and the optimal contracts. We then apply our results to testing for asymmetric information in insurance markets.The authors thank P.A. Chiappori, D. de Mezza, R. Myerson, C. Prendergast, the late S. Rosen, D. Webb and an anonymous referee for helpful discussions or comments, as well as seminar participants in Berkeley, Chicago, Montré al, Northwestern, Rome, Stanford and Wisconsin. Bruno Jullien gratefully acknowledges financial support from the Fédération Francaise des Sociétés d'Assurance; Bernard Salanié thanks the University of Chicago for its hospitality.     

Job matching when employment contracts suffer from moral hazard

We consider a job matching model where the relationships between firms and wealth-constrained workers suffer from moral hazard. Specifically, effort on the job is non-contractible so that parties that are matched negotiate a bonus contract. Higher unemployment benefits affect the workers' outside option. The latter is improved for low-skilled workers. Hence they receive a larger share of the surplus, which strengthens their effort incentives and increases productivity. Effects are reversed for high-skilled workers. Moreover, raising benefit payments affects the proportion of successful matches, which induces some firms to exit the economy and causes unemployment to increase.     

Double moral hazard and renegotiation

We examine renegotiation in a double moral hazard model with an ex ante budget balancing constraint when both the principal and the agent are allowed to make a renegotiation offer even though the principal proposes an initial contract. Under a belief restriction, any perfect-Bayesian equilibrium leads to an allocation that is superior to the second-best allocation of the standard double moral hazard model without renegotiation. The result of this paper gives some reasons for the existence of intermediary organizations such as holding companies, law houses, consulting firms, investment banks or venture capital. The result can also provide the rationalization for a fund set up by a group of firms of the industry in which their product is legally required to be recyclable.     

公司治理道德风险的起源及其机制设计——基于契约不完全的视角

公司治理契约的不完全性诱发了委托代理关系中的当事人道德风险行为,制约着企业经营效率,成为公司治理研究的逻辑起点。文章从契约不完全性视角探讨了公司治理道德风险的本质和起源,并从公司治理当事人委托代理交互关系中指出了委托人-代理人框架、委托人-监督人-代理人框架、知情委托人框架三类道德风险分析框架。结合公司治理道德风险的本源,从微观视角提出了偏好治理机制、声誉治理机制、信息共享机制、横向监督机制以及第三方执行机制五种由弱到强、由内到外的道德风险多层次治理机制,结合国内外研究现状分析了五种治理机制的作用机理。最后,对五种治理机制在公司治理道德风险中的规制效能进行了总结并从外部竞争对内部机制的影响上提出了未来的研究方向。     

Repeated moral hazard with persistence

Summary. This paper considers the optimal contract when the current (hidden) action of an agent has a persistent effect on the future outcome. The optimal contract in a two-effort choice, two-period setting is characterized analytically and numerically. In particular, we show that persistence tends to make compensation less responsive to the first-period outcome. At the extreme, there are cases where the agent is perfectly insured against the first-period outcome: the agent obtains the same utility regardless of the first-period outcome. The model is extended to three periods. We also present a computational method to characterize an N-period model with two-period persistence.Received: 9 December 2003, Revised: 13 February 2004, JEL Classification Numbers: D82, J31, J65. Correspondence to: Ayegül ahinWe are grateful to an anonymous referee, Jack Barron, Mark Bils, Hugo Hopenhayn, Per Krusell, Lance Lochner, Steve Williamson, and seminar participants at Concordia University, Purdue University, the applied theory meetings at University of Rochester, the Conference of the Society for the Advancement of Economic Theory 2003, the Rochester Wegmans Conference 2002, and the Society for Economic Dynamics Meetings 2003 for their comments and suggestions. We also wish to thank Vera Brencic, Nancy Marmon, and Roxanne Stanoprud for excellent research assistance.     

A state-contingent production approach to principal-agent problems with an application to point-source pollution control

Two basic representations of principal-agent relationships, the ‘state-space' and ‘parameterized distribution' formulations, have emerged. Although the state-space formulation appears more natural, analytical studies using this formulation have had limited success. This paper develops a state-space formulation of the moral-hazard problem using a general representation of production under uncertainty. A closed-form solution for the agency-cost problem is derived. Comparative-static results are deduced. Next we solve the principal's problem of selecting the optimal output given the agency-cost function. The analysis is applied to the problem of point-source pollution control.     

Environmental accidents under moral hazard and limited firm liability

We study optimal government policy when firms' operations involve a risk of a large environmental accident, firms do not have sufficient assets to cover such costs, and the risk is affected by firms' efforts which are unobservable to outsiders. When firms' profits and government revenues have equal weights in the social welfare function, a first best can be implemented and requires that the firm be subsidized heavily when operating with no accident, and all its assets confiscated in the event of an accident. With a lower weight on firm profits the solution is always second best, with lower subsidies to the firm, and a firm effort lower than at the first-best solution. When firm investments affect both the required accident-preventing effort for given risk and the work effort required for a given output, the first best never involves specific investment subsidies, while a second-best solution generally always does.The paper is part of the research project Environmental policy under asymmetric information', at the SNF Centre for research in economics and business administration, Department of Economics, University of Oslo. I thank, without implicating, Mikael Hoel, Jean-Charles Rochet, Jean Tirole, and two anonymous referees for helpful comments on a preliminary version.     

二级供应链中代理人的甄别与激励研究

文章分析了由一个制造商与一个分销商所组成的二级供应链中,既存在契约签订之前的逆向选择问题又存在契约签订之后的道德风险问题这一情况下,制造商对分销商的类型甄别及努力激励的机制设计问题。主要得到以下结论：①制造商可以通过努力收益分享的方式激励销售商投入最优的努力水平,进而规避道德风险行为。②制造商通过设计一组激励相容机制可以达到甄别分销商类型的目的,但必须支付给高销售能力分销商一定的租金。③高销售能力分销商的销量水平不存在扭曲,而低销售能力分销商的销量水平向下扭曲,其原因在于制造商降低给低销售能力分销商规定的销量就能够降低支付给高销售能力分销商的信息租金。文章从供应链中逆向选择与道德风险共存的角度对供应链委托代理关系进行研究,得出结论为供应链中的委托代理双方提供了一定的决策依据。     

Moral hazard and general equilibrium in large economies

Summary. The paper analyzes a two period general equilibrium model with individual risk, aggregate uncertainty and moral hazard. There is a large number of households, each facing two individual states of nature in the second period. These states differ solely in the household's vector of initial endowments, which is strictly larger in the first state (good state) than in the second state (bad state). In the first period each household chooses a non-observable action. Higher levels of action give higher probability of the good state of nature to occur, but lower levels of utility. Households' utilities are assumed to be separable in action and the aggregate uncertainty is independent of the individual risk. Insurance is supplied by a collection of firms who behave strategically and maximize expected profits taking into account that each household's optimal choice of action is a function of the offered contract. The paper provides sufficient conditions for the existence of equilibrium and shows that the appropriate versions of both welfare theorems hold. Received: December 7, 1998; revised version: October 25, 1999     

金融虚拟化的道德风险及其市场影响:次贷危机的深层反思

由美国次贷危机引发的全球性金融危机和全球性经济衰退仍在蔓延之中,至今仍深未见底。从表面上看是美国房地产泡沫的破灭引发了次贷危机的爆发,但从本质上分析,次级抵押贷款证券化、衍生化和虚拟化过程中各参与主体的道德风险行为才是引发危机的真正根源。正是不断虚拟化所引发的市场信息不对称的加剧为各环节的金融中介提供了道德风险行为的空间;而金融中介道德风险行为的加剧和叠加则增加了金融市场的脆弱性,提高了金融市场的系统风险,最终导致危机的全面爆发。     

Task scheduling and moral hazard

We study a two-period moral hazard problem with risk-neutral and wealth-constrained agents and three identical tasks. We show that the allocation of tasks over time is important if there is a capacity constraint on the number of tasks that can be performed in one period. We characterize the optimal schedule of tasks over time and the optimal assignment of tasks to agents conditional on the outcomes of previous tasks. In particular, we show that delaying tasks is optimal if and only if the effect of an agent’s effort on the probability of success is relatively low. We have benefitted from helpful discussions with A. Roider, L. Samuelson, and U. Schweizer. The paper has been substantially improved due to the detailed and very valuable comments of an Associate Editor. Financial support by Deutsche Forschungsgemeinschaft, SFB/TR15, is gratefully acknowledged.     

Knightian uncertainty and moral hazard

This paper presents a principal-agent model in which the agent has imprecise beliefs. We model this situation formally by assuming the agent?s preferences are incomplete as in Bewley (1986) [2]. In this setting, incentives must be robust to Knightian uncertainty. We study the implications of robustness for the form of the resulting optimal contracts. We give conditions under which there is a unique optimal contract, and show that it must have a simple flat payment plus bonus structure. That is, output levels are divided into two sets, and the optimal contract pays the same wage for all output levels in each set. We derive this result for the case in which the agent?s utility function is linear and then show it also holds if this utility function has some limited curvature.     

Repeated moral hazard with effort persistence

I study a problem of repeated moral hazard where the effect of effort is persistent over time: each period's outcome distribution is a function of a geometrically distributed lag of past efforts. I show that when the utility of the agent is linear in effort, a simple rearrangement of terms in his lifetime utility translates this problem into a related standard repeated moral hazard. The solutions for consumption in the two problems are observationally equivalent, implying that the main properties of the optimal contract remain unchanged with persistence. For illustration, I present the computed solution of an example.     

Dynamic risk-sharing with two-sided moral hazard

A group of risk-averse agents repeatedly produce a perishable consumption good; individual outputs are observable but efforts are not. The contracting problem admits a recursive formulation, and the optimal value function is the fixed point of a contraction mapping. When the agents can be punished to the full extent in a single period, every continuation contract of an optimal contract is itself optimal; the marginal utility ratio between one agent and another is a submartingale. The results imply that it is in general important to restrict an agent whose moral hazard constraint is binding from saving through another agent within the risk-sharing group. Limited commitment and long-run implications of optimal contracting are also examined.