Insurers can exploit the heterogeneity within risk-adjustment classes to select the good risks because they have more information than the regulator on the expected expenditures of individual insurees. To counteract this cream skimming, mixed systems combining capitation and cost-based payments...

The literatures on differential commodity taxes and on quantity controls to supplement income taxation have developed separately. This paper combines these two strands in the standard framework of optimal nonlinear income taxation. The authors use a model with two types of households where the...