This paper reviews the record of randomized field trials in welfare reform and assesses the implications of that record for the use of randomization.

This paper explores the identifiability of ratios of derivatives of the index function in a model of a duration process in which the impact of covariates on the hazard function passes through a single index.

We provide easy to verify suffcient conditions for the consistency and asymptotic normality

Four alternative but related approaches to empirical evaluation of policy interventions are studied.

This paper studies the estimation of conditional quantiles of counts.

new methodology that estimates attitudes semiparametrically and estimates actions nonparametrically, as a function of the resulting attitudinal measures, is used to examine the behavioral effects of cultural and economic preferences in the Presidential elections of 1984 and 1992.

This paper studies the identification of partial differences of nonseparable structural functions.

ExpEnd is a Gauss programme for non-linear generalised method of moments (GMM) estimation of exponential models with endogenous regressors for cross section and panel data.

This paper describes an estimator of the additive components of a nonparametric additive model with a known link function.

We consider the identification of the average treatment effect in models with continuous endogenous variables whose impact is heterogeneous.