We develop a methodology to sign output distortions in the random participation framework. We apply our method to monopoly nonlinear pricing problem, to the regulatory monopoly problem and mainly to the optimal income tax problem. In the latter framework, individuals are heterogeneous across two...

This paper characterizes the optimal redistributive tax schedule in a matching unemployment framework where (voluntary) nonparticipation and (involuntary) unemployment are endogenous. The optimal employment tax rate is given by an inverse employment elasticity rule. This rule depends on the...

We derive a general optimal income tax formula when individuals respond along both the intensive and extensive margins and when income effects can prevail. Individuals are heterogeneous across two dimensions: their skill and their disutility of participation. Prefer-ences over consumption and...

This paper examines optimal redistribution in a model with high- and low-skilled individuals with heterogeneous tastes for labor. We compare the extent to which optimal policies based on different normative criteria obey the principles of compensation (for differential skills) and responsibility...

This paper studies the optimal income redistribution and optimal monitoring when disability benefits are intended for disabled people but when some able agents with high distaste for work mimic them (type II errors). Labor supply responses are at the extensive margin and endogenous take-up costs...

This article explores the use of workfare as part of an optimal tax mix when labor supply responses are along the extensive margin. Particular attention is paid to the interaction between workfare and an earned income tax credit, two policies that are designed to provide additional incentives...

We solve a large class of multidimensional adverse selection problems with one observed action, to derive the nonlinear optimal income tax schedule when individuals differ along multiple unobserved characteristics. Based on a perturbation of the optimal allocation, our method allows individuals...

This paper studies equilibrium unemployment in a two-region economy with matching frictions, where workers and jobs are free to move and wages are bargained over. Job-seekers choose between searching locally or searching in both regions. Search-matching externalities are amplified by the latter...

This paper develops a partial equilibrium job search model to study the behavioral and welfare implications of an Unemployment Insurance (UI) scheme in which job search requirements are imposed on UI recipients with hyperbolic preferences. We show that, if the search requirements are well...

The current unemployment insurance and employment protection legislation were set up in an environment in which relationships between workers and firms were typically long-lasting and stable. The increasing globalisation of the economy and the rapid technological and organisational changes...