This dissertation studies moral hazard problems and an information acquisition problem in dynamic economic environments. In chapter 1, I study a continuous-time principal-agent model in which a risk-neutral agent protected by limited liability exerts costly efforts to manage a project for her principal. Unobserved risk-taking by the agent is value-reducing in the sense that it increases the chance of large losses, even though it raises short-term profits. In the optimal contract, severe punishment that follows a large loss prevents the agent from taking hidden risks. However, after some histories, punishment can no longer be used because of limited liability. The principal allows the agent to take hidden risk when the firm is close to liquidation. In addition, I explore the roles of standard securities in implementing the optimal contract. The implementation shows that driven by the agency conflicts, incomplete hedging against Poisson risk provides incentives for the agent to take the safe project. Moreover, I study the optimality of "high-water mark" contract widely used in the hedge fund industry and find that "distance-to-threshold" is important in understanding the risk-shifting problem in a dynamic context. In chapter 2, I study a continuous-time moral hazard model in which the principal hires a team of agents to run the business. The firm consists of multiple divisions and agents exert costly efforts to improve the divisional cash flows. The firm size evolves stochastically based on the aggregate cash flows.The model delivers a negative relationship between firm sizes and pay-for-divisional incentives, and I characterize conditions under which joint/relative performance evaluation will be used. I also explore the implications of team production on the firm's optimal capital structure and financial policy. In chapter 3, I study a multi-armed bandits problem with ambiguity. Decision-maker views the probabilities underlying each arm as imprecise and his preference is represented by recursive multiple-priors. I show that the classical "Gittins Index" generalizes to a "Multiple-Priors Gittins Index". In the setting with one safe arm and one ambiguous arm, the decision-maker plays the ambiguous arm if its "Multiple-Priors Gittins Index" is higher than the return delivered by the safe arm. In the multi-armed environment, I obtain the "Multiple-Priors Index Theorem" which states that the optimal strategy for the decision-maker is to play the ambiguous arm with the highest Multiple-Priors Index.

This dissertation analyzes the contracting problem between a firm and the research employees in its R&D department. The dissertation consists of two chapters. The first chapter addresses a simplified problem in which the R&D unit has only one agent. The second chapter studies a scenario in which the R&D unit consists of a team. In the first chapter, I look at problem in which a principal hires an agent to do a multi-stage R&D project. The transition from one stage to the next is modeled by a Poisson-type process, whose arrival rate depends on the agents choice of effort. I assume that effort choice is binary and unobservable by the principal. To overcome the repeated moral-hazard problem, the principal offers the agent a long-term contract which specifies a flow of payments based on his observation of the outcome of the project. The optimal contract combines rewards and punishments: the payment to the agent decrease over time in case of failure and jumps up to a higher level after each success. I also show that the optimal contract can be implemented by using a risky security that has some of the features of the stocks of these firms, thereby providing a theoretical justification for the wide-spread use of stock-based compensation in firms that rely on R&D. In the second chapter, I look at a scenario in which the R&D unit consists of a team, which I assume, for simplicity, comprises two risk-averse agents. Now, the Poisson arrival rate is jointly determined by the actions of both agents with the action of each remaining unobservable by both the principal and the other agent. I assume that when success in a phase occurs the principal can identify the agent who was responsible for it. In this model, incentive compatibility means that each agent is willing to exert effort conditional on his coworker putting in effort, and thus exerting effort continuously is a Nash-equilibrium strategy played by the agents. In this multiagent problem, each agents payment depends not only on his own performance, but is affected by the other agents performance as well. Similar to the single-agent case, an agent is rewarded when he succeeds, and his payment decreases over time when both agents fail. Regarding how an agents payment relates to his coworkers performance, I find that the optimal incentive regime is a function of the way in which agents efforts interact with one another: relative-performance evaluation is used when their efforts are substitutes whereas joint-performance evaluation is used when their efforts are complements. This result sheds new light on the notion of optimal incentive regimes, an issue that has been widely discussed in multi-agent incentive problems.

This thesis is divided into two parts. Part I deals with demand management. For goods with no substitutes, under supply constraints, fairness considerations introduce negative externalities and lead to a market failure. One example of such a good with no substitutes is water. In case of a market failure, it is necessary to design coordination mechanisms called contracts which provide the right incentives for coordination. As “repetition can yield coordination”, the aim in this part is to design price based dynamic demand management contracts which, under supply constraints, mitigate the market failure. In these contracts, we consider complete information settings; and use the status quo proposition as a fairness criterion for designing them. The contracts are designed as almost noncooperative dynamic games, within the agency theory framework, where the agent (the consumer) is induced to consume at a specified consumption level based on the incentive mechanism offered by the principal (the producer). These contracts use the solution concept of sub-game perfect Nash equilibrium (SPNE) to compute the price (mal-incentive) that acts as a credible threat for deviation from the specified consumption level. In these contracts, unlike the dynamic contracts with asymmetric information, the penalty for deviation is proportional to the amount of deviation. First, we consider a two-period demand management contract for a single consumer satisfying the status quo proposition. Under the assumption that the gain to the consumer and the loss to the producer by deviation is small, the contract is shown to be economically efficient. It is shown that, in the finite horizon, a fair demand management contract cannot be efficient. The demand management contract is homeomorphic to finite horizon alternating bargaining model. In the finite horizon alternating bargaining model, there is a unique SPNE, in which the player who offers last is always at an advantageous position. In the two-period contract, the assumption considered attenuates the last mover advantage and leads to the efficiency. We have shown that one possible way to achieve efficiency, without the assumption, is to make the agents uncertain about the period of interaction. This possibility can be included in an infinite horizon contract. Hence, next, we design an infinite horizon contract for a single consumer. It is proved that this contract is economically efficient and provides revenue sufficiency. The sensitivity analysis of the contract shows that the discounting rate measures the aversion to conservation characteristics of the consumer. The analysis of the contract shows that a sufficiently time-patient consumer is not penalized for the deviation, as the consumer himself is aware of conservation requirements. This result is similar to the results for the present-biased preferences in behavioral economics. Lastly, the infinite horizon contract is extended to two consumers case which internalizes the externality a consumer causes to another. In the two consumer case, consumers are strategically noninteracting; and it is shown that the producer acts as a budget balancer. These contracts are also shown to be economically efficient. The demand management contracts achieve both the procedural and end-state fairness. Also, the infinite horizon contracts are homeomorphic to infinite horizon alternating bargaining model. The efficiency of infinite horizon contracts is due to their homeomorphism with the alternating bargaining process as they exhaust all possible mutual gains from exchange. In the two-period model, the bargaining process is constrained and hence all possible mutual gains are not eliminated, leading to the inefficiency. In part II of the thesis, we discuss the notions of exchangeability in the Shapley value. The Shapley value is a probabilistic value for the transferable utility (TU) cooperative games, in which each player subjectively assigns probabilities to the events which define their positions in the game. In this part, the objective have been to explore the aspect of subjective probability which leads to the uniqueness of the Shapley value. This aspect of subjective probability is known as exchangeability. We derive the Shapley value using de Finetti’s theorem. We also show that, in the Shapley value, each player’s prospects of joining a t-player game as the last member of the game is a moment sequence of the uniquely determined uniform distribution. We stress on finite exchangeability; and deduce that, with finite exchangeability, the Shapley value is the only value in which the probability assignment is a unique mixture of independent and identical distributions. It is concluded that, in both the finite and infinite exchangeable cases, the uniqueness of probability assignment in the Shapley value is due to exchangeability and the mixing with the uniform distribution.

Cette thèse analyse l'effet de la législation de protection de l'emploi sur le taux de chômage, les salaires et la productivité des entreprises. En particulier, je m'intéresse dans cette thèse à l’effet de la réglementation des licenciements et des contrats de travail temporaires. Cette question de recherche est motivée par le fait que dans de nombreux pays de l’OCDE, la législation combine des coûts de licenciements élevés et des restrictions faibles sur les contrats temporaires, ce qui entraîne, d’après un certain nombre d’économistes, une segmentation du marché du travail. Le premier chapitre défend l’idée qu’il est important de comprendre les mécanismes qui expliquent le choix des entreprises de signer des contrats temporaires ou permanents afin d'évaluer l’effet de la protection de l’emploi. Ce chapitre analyse un problème de contrat dynamique entre un travailleur averse au risque et un employeur neutre vis-à-vis du risque. Dans ce chapitre, je soutiens notamment que le choix du type d'emploi est déterminé par un arbitrage entre les gains associés au partage du risque qu’offre un emploi permanent et les gains associés à la flexibilité qu’offre un emploi temporaire. Le deuxième chapitre construit un modèle du marché du travail caractérisé par des frictions de recherche et d’appariement, dans lequel le contrat dynamique du chapitre 1 est intégré. Je propose ainsi un modèle dans lequel l’allocation des agents au sein des différents types d’emplois est déterminée de façon endogène par des considérations reliées au partage du risque. Le modèle, calibré pour reproduire les caractéristiques du marché du travail en France durant les années 2000, suggère que les contrats temporaires ont tendance à augmenter la productivité des entreprises mais également le taux de chômage. Le dernier chapitre propose un modèle de cycle de vie visant à évaluer les effets des coûts de licenciement sur l’emploi et les salaires en fonction du niveau d’éducation et d’expérience. Le modèle est calibré sur les données d’enquête sur la main d’œuvre en France durant les années 2000. Une série d'expériences contrefactuelles indiquent que les coûts de licenciement ont un effet négatif sur l’emploi, concentré principalement sur les jeunes travailleurs avec un niveau d’éducation faible. En revanche, cet effet semble être négligeable pour les travailleurs avec un niveau d'expérience et d'éducation élevé. / This thesis analyzes the effect of employment protection on labor market outcomes. The thesis focuses on the impact of firing restrictions and the regulation of temporary contracts. In many OECD countries, the employment protection legislation combines high firing restrictions and relatively lax regulation of temporary jobs which is, according to several economists, a source of labor market segmentation. The first chapter argues that analyzing the effect of employment protection requires to understand how economic agents choose between permanent and temporary contracts. This chapter examines a dynamic employment contract between a risk-averse worker and a risk-neutral firm. I argue in this chapter that the choice between a permanent and a temporary contract is driven by a trade-off between efficient risk-sharing and flexibility. The second chapter builds a model of the labor market with search frictions, in which the contracting problem of chapter 1 is embedded. Thus, this chapter proposes a model in which the allocation of agents into permanent and temporary jobs is endogenous to risk-sharing considerations. The model is calibrated to the features of the French labor market during the 2000s and indicates that temporary contracts tend to increase productivity but unemployment as well. The third chapter proposes a life-cycle model to evaluate the effect of firing costs across different experience and education groups. The model is calibrated using a French labor force survey dataset. Policy experiments suggest that firing costs have a negative effect on employment, which is concentrated on low experience and education workers.