Knowledge that Transforms

Many believe that a key innovation by the Grameen Bank is to encourage borrowers to help each other in hard times. To analyse this, we study a mechanism design problem where borrowers share information about each other, but their limited side contracting ability prevents them from writing complete insurance contracts. We derive a lending mechanism which efficiently induces mutual insurance. It is necessary for borrowers to submit reports about each other to achieve efficiency. Such cross-reporting increases the bargaining power of unsuccessful borrowers, and is robust to collusion against the bank.

We develop generalized indirect estimation procedures that handle equality and inequality constraints on the auxiliary model parameters by extracting information from the relevant multipliers, and compare their asymptotic efficiency to maximum likelihood. We also show that, regardless of the validity of the restrictions, the asymptotic efficiency of such estimators can never decrease by explicitly considering the multipliers associated with additional equality constraints. Furthermore, we discuss the variety of effects on efficiency that can result from imposing constraints on a previously unrestricted model. As an example, we consider a stochastic volatility process estimated through a garch model with Gaussian or t distributed errors.

Many strategic interactions in the real world take place among delegates empowered to act on behalf of others. Although there may be a multitude of reasons why delegation arises in reality, one intriguing possibility is that it yields a strategic advantage to the delegating party. In the case where only one party has the option to delegate, we analyse the possibility that strategic delegation arises as an equilibrium outcome under completely unobservable incentive contracts within the class of two-person extensive form games. We show that delegation may arise solely due to strategic reasons in quite general economic environments even under unobservable contracts. Furthermore, under some reasonable restrictions on out-of-equilibrium beliefs and actions of the outside party, strategic delegation is shown to be the only equilibrium outcome.

We provide an asymptotic distribution theory for a class of generalized method of moments estimators that arise in the study of differentiated product markets when the number of observations is associated with the number of products within a given market. We allow for three sources of error: sampling error in estimating market shares, simulation error in approximating the shares predicted by the model, and the underlying model error. It is shown that the estimators are CAN provided the size of the consumer sample and the number of simulation draws grow at a large enough rate relative to the number of products. We consider the implications of the results for the Berry, Levinsohn and Pakes (1995) random coefficient logit model and the pure characteristics model analysed in Berry and Pakes (2002). The required rates differ for these two frequently used demand models. A small Monte Carlo study shows that the differences in asymptotic properties of the two models are reflected, in quite a striking way, in the models' small sample properties. Moreover the limit distributions provide a good approximation to the actual Monte Carlo distribution of the parameter estimates. The results have important implications for the computational burden of the two models.

This paper examines monopoly power in the market for groundwater (irrigation water extracted by private tubewells), a market characterized by barriers to entry and spatial fragmentation. In Pakistan's Punjab region, groundwater and tenancy contracts are often interlinked, with share-tenants gaining access to water through the use of their landlord's tubewell. An analysis of groundwater transactions shows that tenants of tubewell owners are charged lower prices than other customers. Tubewell owners and their tenants also use considerably more groundwater on their plots than other farmers. Using detailed price and quantity data, the efficiency and distributional implications of this monopoly power are explored.

We provide empirical restrictions of a model of optimal order submissions in a limit order market. A trader's optimal order submission depends on the trader's valuation for the asset and the trade-offs between order prices, execution probabilities and picking off risks. The optimal order submission strategy is a monotone function of a trader's valuation for the asset. We test the monotonicity restriction in a sample of order submissions and their realized outcomes from the Stockholm Stock Exchange. We do not reject the monotonicity restriction for buy orders or sell orders considered separately, but reject the monotonicity restriction for buy and sell orders considered jointly.

Standard models of employment fluctuations cannot reconcile the unemployment rate's remarkable persistence with the high job-finding rates found in worker flows data. A matching model emphasizing high hazard rates among newly formed firm-worker matches can resolve this shortcoming. In the model, matches are experience goods; consequently, newly employed workers face higher hazard rates.Following a job loss, workers may experience several short-lived jobs before finding stable employment. At an aggregate level, an initial burst of job loss precipitates a steady flow of recurring job loss. A simulation shows that this recurring job loss can account for the fact that the unemployment rate remains elevated for as much as 4 or 5 years following an initial jump. Copyright The Review of Economic Studies Limited, 2004.

Previous work has had difficulty generating household saving behavior that makes the distribution of wealth much more concentrated than that of labor earnings, and that makes the richest households hold onto large amounts of wealth, even during very old age. I construct a quantitative, general equilibrium, overlapping-generations model in which parents and children are linked by accidental and voluntary bequests and by earnings ability. I show that voluntary bequests can explain the emergence of large estates, while accidental bequests alone cannot, and that adding earnings persistence within families increases wealth concentration even more. I also show that the introduction of a bequest motive generates lifetime savings profiles more consistent with the data.

This paper develops and implements semiparametric methods for estimating binary response (binary choice) models with continuous endogenous regressors. It extends existing results on semiparametric estimation in single-index binary response models to the case of endogenous regressors. It develops a control function approach to account for endogeneity in triangular and fully simultaneous binary response models. The proposed estimation method is applied to estimate the income effect in a labour market participation problem using a large micro data-set from the British Family Expenditure Survey. The semiparametric estimator is found to perform well, detecting a significant attenuation bias. The proposed estimator is contrasted to the corresponding probit and linear probability specifications.