This paper presents methods for evaluating the effects of reallocating an indivisible input across production units, taking into account resource constraints by keeping the marginal distribution of the input fixed. When the production technology is nonseparable, such reallocations, although...

In this paper we nonparametrically analyze the effects of reallocating individuals across social groups in the presence of social spillovers. Individuals are either 'high' or 'low' types. Own outcomes may vary with the fraction of high types in one's social group. We characterize the average...

We propose a generalization of the linear quantile regression model to accommodate possibilities afforded by panel data. Specifically, we extend the correlated random coefficients representation of linear quantile regression (e.g., Koenker, 2005; Section 2.6). We show that panel data allows the...

I formalize a widely-used empirical model of network formation. The model allows for assortative matching on observables (homophily) as well as unobserved agent level heterogeneity in link surplus (degree heterogeneity). The joint distribution of observed and unobserved agent-level...

Social and economic networks are ubiquitous, serving as contexts for job search, technology diffusion, the accumulation of human capital and even the formulation of norms and values. The systematic empirical study of network formation - the process by which agents form, maintain and dissolve...

We add health and longevity to a standard model of life cycle saving and show that, under plausible assumptions, increases in longevity lead to higher savings rates at every age, even when retirement is endogenous. In a stable population these higher savings rates are offset by increased old age...

We propose a new inverse probability weighting (IPW) estimator for moment condition models with missing data. Our estimator is easy to implement and compares favorably with existing IPW estimators, including augmented inverse probability weighting (AIPW) estimators, in terms of efficiency,...

In this paper we study identification and estimation of a correlated random coefficients (CRC) panel data model. The outcome of interest varies linearly with a vector of endogenous regressors. The coefficients on these regressors are heterogenous across units and may covary with them. We...

This paper shows that the semiparametric efficiency bound for a parameter identified by an unconditional moment restriction with data missing at random (MAR) coincides with that of a particular augmented moment condition problem. The augmented system consists of the inverse probability weighted...

We propose a locally efficient estimator for a class of semiparametric data combination problems. A leading estimand in this class is the Average Treatment Effect on the Treated (ATT). Data combination problems are related to, but distinct from, the class of missing data problems analyzed by...