With reference to the EU enlargement, a framework is derived which allows the study of the effect of unemployment benefits on the migration decision. While benefits simply increase the expected gain for risk neutral individuals, they work as an insurance device for risk averse migrants; the...

This paper investigates four topics. (1) It examines the different roles played by the propensity score (probability of selection) in matching, instrumental variable and control functions methods. (2) It contrasts the roles of exclusion restrictions in matching and selection models. (3) It...

This paper summarizes our recent research on evaluating the distributional consequences of social programs. This research advances the economic policy evaluation literature beyond estimating assorted mean impacts to estimate distributions of outcomes generated by different policies and determine...

The paper provides a new proof of the positivity of the optimal marginal income tax, in a more general model, under weaker assumptions. The analysis focusses on the (weakly) relaxed problem in which upward incentive constraints are replaced by a monotonicity condition on consumption. Without...

For the standard specification of the utilitarian optimal income tax problem with hidden characteristics, the paper shows that randomized tax schemes are undesirable if preferences exhibit a property of weakly decreasing risk aversion according to the multidimensional risk aversion concept of...

We study the environmental and economic effects of public abatement in the presence of multiple stable steady-state ecological equilibria. Under shallow-lake dynamics (SLD), the isocline for the stock of pollution features two stable branches, a good and a bad one. Assuming that the ecology is...

This paper develops a model of skill formation that explains a variety of findings established in the child development and child intervention literatures. At its core is a technology that is stage-specific and that features self productivity, dynamic complementarity and skill multipliers....

This paper extends the widely used ordered choice model by introducing stochastic thresholds and interval-specific outcomes. The model can be interpreted as a generalization of the GAFT (MPH) framework for discrete duration data that jointly models durations and outcomes associated with...