Adverse Selection, Credit, and Efficiency: the Case of the Missing Market

We analyze a standard environment of adverse selection in credit markets. In our envi- ronment, entrepreneurs who are privately informed about the quality of their projects need to borrow from banks. As is generally the case in economies with adverse selection, the competitive equilibrium of our economy is shown to be ine¢ cient. Under adverse selection, the choices made by one type of agents limit what can be o¤ered to other types in an incentive-compatible manner. This gives rise to an externality, which cannot be internalized in a competitive equilibrium. We show that, in this type of environment, the ine¢ ciency associated to adverse selection is the consequence of one implicit assumption: entrepreneurs can only borrow from banks. If an additional market is added (say, a .security market.), in which entrepreneurs can obtain funds beyond those o¤ered by banks, we show that the e¢ cient allocation is an equilibrium of the economy. In such an equilibrium, all entrepreneurs borrow at a pooling rate in the security market. When they apply to bank loans, though, only entrepreneurs with good projects pledge these additional funds as collateral. This equilibrium thus simultaneously entails cross- subsidization and separation between di¤erent types of entrepreneurs.

Adverse selection, credit, and efficiency: the case of the missing market

We analyze a standard environment of adverse selection in credit markets. In our environment, entrepreneurs who are privately informed about the quality of their projects need to borrow in order to invest. Conventional wisdom says that, in this class of economies, the competitive equilibrium is typically inefficient. We show that this conventional wisdom rests on one implicit assumption: entrepreneurs can only access monitored lending. If a new set of markets is added to provide entrepreneurs with additional funds, efficiency can be attained in equilibrium. An important characteristic of these additional markets is that lending in them must be unmonitored, in the sense that it does not condition total borrowing or investment by entrepreneurs. This makes it possible to attain efficiency by pooling all entrepreneurs in the new markets while separating them in the markets for monitored loans.

Optimal Contracts, Adverse Selection, and Social Preferences: An Experiment

It has long been standard in agency theory to search for incentive-compatible mechanisms on the assumption that people care only about their own material wealth. However, this assumption is clearly refuted by numerous experiments, and we feel that it may be useful to consider nonpecuniary utility in mechanism design and contract theory. Accordingly, we devise an experiment to explore optimal contracts in an adverse-selection context. A principal proposes one of three contract menus, each of which offers a choice of two incentive-compatible contracts, to two agents whose types are unknown to the principal. The agents know the set of possible menus, and choose to either accept one of the two contracts offered in the proposed menu or to reject the menu altogether; a rejection by either agent leads to lower (and equal) reservation payoffs for all parties. While all three possible menus favor the principal, they do so to varying degrees. We observe numerous rejections of the more lopsided menus, and approach an equilibrium where one of the more equitable contract menus (which one depends on the reservation payoffs) is proposed and agents accept a contract, selecting actions according to their types. Behavior is largely consistent with all recent models of social preferences, strongly suggesting there is value in considering nonpecuniary utility in agency theory.

A Model of Collateral, Investment, and Adverse Selection

This paper characterizes the relationship between entrepreneurial wealth and aggregate investment under adverse selection. Its main finding is that such a relationship need not be monotonic. In particular, three results emerge from the analysis: (i) pooling equilibria, in which investment is independent of entrepreneurial wealth, are more likely to arise when entrepreneurial wealth is relatively low; (ii) separating equilibria, in which investment is increasing in entrepreneurial wealth, are most likely to arise when entrepreneurial wealth is relatively high and; (iii) for a given interest rate, an increase in entrepreneurial wealth may generate a discontinuous fall in investment.

Protocols psicològics d’actuació en situacions de crisi en el medi penitenciari

Una de les qüestions que ens preocupen com a psicòlegs i psicòlogues en l'àmbit penitenciari és saber fer front d’una manera vàlida i efectiva a les diverses situacions de crisi o emergència que es produeixen en aquest medi, encara que sigui puntualment, no per això deixen de ser significatives i a vegades traumàtiques, tant per a les persones preses com per al seu context. Tanmateix, som conscients que els professionals que assisteixen les persones o grups en crisi a la presó no són necessàriament psicòlegs, sinó que sovint són els funcionaris de vigilància o els mateixos membres de la direcció del centre els que han d’assumir aquestes funcions. És com a tècnics especialistes en el comportament i la personalitat humana i en la solució dels problemes relacionals que podem col·laborar i assessorar els responsables en la gestió d’aquests conflictes en procediments i estratègies del tractament més efectius a l’hora de negociar i assolir un equilibri adaptatiu entre les diverses parts que conformen els escenaris en crisi. Un dels objectius que ens plantejarem la comunitat de pràctiques en aquest curs 2009 és identificar les diverses situacions de crisi que es poden produir a la presó i elaborar un conjunt de protocols d’actuació psicològica que orientin el professional (el psicòleg inicialment però també d’altres agents del canvi dels comportaments antisocials) sobre quina és la millor manera d’intervenir-hi. No obstant això, es considera que més enllà de l'elaboració de guies o manuals d’intervenció (al cap i a la fi això es pot consultar en la literatura especialitzada sobre aquest tema), es tractava de ser el més pràctics possible i recollir en un tríptic aquella informació pertinent (allò imprescindible que s’ha de saber per actuar de manera efectiva i quins són els errors que cal evitar encara que només sigui per no complicar encara més les coses) que fos fàcil d’utilitzar per part del professional, és a dir, un recordatori esquematitzat però rigorós del pla d’acció que cal seguir per fer front a la crisi. També es pretén que sigui obert a les experiències i coneixements resolutius de qui intervé en aquestes situacions d’emergència i que permeti el feedback amb el grup de la comunitat de pràctiques, qui ho validaria, per tal d’anar incrementat progressivament la validesa i fiabilitat de l'instrument. Aquest curs presentem dos protocols/tríptics d’actuació: 1) notificació de males noticies/acompanyament en el dol; 2) intervenció en el risc de suïcidi o en conductes de autòlisi. La idea és elaborar-ne més en pròximes edicions. A més a més, com a protocol en format audiovisual, es presenta un curtmetratge on es desenvolupa una actuació psicològica per tal de desactivar una conducta violenta/ amenaçant.

Interviews and adverse selection

Interviewing in professional labor markets is a costly process for firms. Moreover, poor screening can have a persistent negative impact on firms bottom lines and candidates careers. In a simple dynamic model where firms can pay a cost to interview applicants who have private information about their own ability, potentially large inefficiencies arise from information-based unemployment, where able workers are rejected by firms because of their lack of offers in previous interviews. This effect may make the market less efficient than random matching. We show that the first best can be achieved using either a mechanism with transfers or one without transfers.

Adverse selection, credit and efficiency: The case of the missing market

We analyze a standard environment of adverse selection in credit markets. In our environment,entrepreneurs who are privately informed about the quality of their projects need toborrow from banks. Conventional wisdom says that, in this class of economies, the competitiveequilibrium is typically inefficient.We show that this conventional wisdom rests on one implicit assumption: entrepreneurscan only borrow from banks. If an additional market is added to provide entrepreneurs withadditional funds, efficiency can be attained in equilibrium. An important characteristic of thisadditional market is that it must be non-exclusive, in the sense that entrepreneurs must be ableto simultaneously borrow from many different lenders operating in it. This makes it possible toattain efficiency by pooling all entrepreneurs in the new market while separating them in themarket for bank loans.

Adverse selection, credit and efficiency: The case of the missing market

We analyze a standard environment of adverse selection in credit markets. In our environment,entrepreneurs who are privately informed about the quality of their projects needto borrow in order to invest. Conventional wisdom says that, in this class of economies, thecompetitive equilibrium is typically inefficient.We show that this conventional wisdom rests on one implicit assumption: entrepreneurscan only access monitored lending. If a new set of markets is added to provide entrepreneurswith additional funds, efficiency can be attained in equilibrium. An important characteristic ofthese additional markets is that lending in them must be unmonitored, in the sense that it doesnot condition total borrowing or investment by entrepreneurs. This makes it possible to attainefficiency by pooling all entrepreneurs in the new markets while separating them in the marketsfor monitored loans.

Hiring and firing costs, adverse selection and long-term unemployment

In this paper, we present a matching model with adverse selection that explains why flows into and out of unemployment are much lower in Europe compared to North America, while employment-to-employment flows are similar in the two continents. In the model,firms use discretion in terms of whom to fire and, thus, low quality workers are more likely to be dismissed than high quality workers. Moreover, as hiring and firing costs increase, firms find it more costly to hire a bad worker and, thus, they prefer to hire out of the pool of employed job seekers rather than out of the pool of the unemployed, who are more likely to turn out to be 'lemons'. We use microdata for Spain and the U.S. and find that the ratio of the job finding probability of the unemployed to the job finding probability of employed job seekers was smaller in Spain than in the U.S. Furthermore, using U.S. data, we find that the discrimination of the unemployed increased over the 1980's in those states that raised firing costs by introducing exceptions to the employment-at-will doctrine.

Improved estimation of the covariance matrix of stock returns with an application to portofolio selection

This paper proposes to estimate the covariance matrix of stock returnsby an optimally weighted average of two existing estimators: the samplecovariance matrix and single-index covariance matrix. This method isgenerally known as shrinkage, and it is standard in decision theory andin empirical Bayesian statistics. Our shrinkage estimator can be seenas a way to account for extra-market covariance without having to specifyan arbitrary multi-factor structure. For NYSE and AMEX stock returns from1972 to 1995, it can be used to select portfolios with significantly lowerout-of-sample variance than a set of existing estimators, includingmulti-factor models.

Dynamic adverse selection and debt

This paper argues that the strategic use of debt favours the revelationof information in dynamic adverse selection problems. Our argument is basedon the idea that debt is a credible commitment to end long term relationships.Consequently, debt encourages a privately informed party to disclose itsinformation at early stages of a relationship. We illustrate our pointwith the financing decision of a monopolist selling a good to a buyerwhose valuation is private information. A high level of (renegotiable)debt, by increasing the scope for liquidation, may induce the highvaluation buyer to buy early at a high price and thus increase themonopolist's expected payoff. By affecting the buyer's strategy, it mayreduce the probability of excessive liquidation. We investigate theconsequences of good durability and we examine the way debt mayalleviate the ratchet effect.

Long-run selection and the work ethic

That individuals contribute in social dilemma interactions even when contributing is costly is a well-established observation in the experimental literature. Since a contributor is always strictly worse off than a non-contributor the question is raised if an intrinsic motivation to contribute can survive in an evolutionary setting. Using recent results on deterministic approximation of stochastic evolutionary dynamics we give conditions for equilibria with a positive number of contributors to be selected in the long run.