This paper characterizes optimal income taxation when individuals respond along both the intensive and extensive margins. Individuals are heterogeneous across two dimensions: specifically, their skill and disutility of participation. Preferences over consumption and work effort can differ with...

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...