The Self-Sufficiency Project (SSP) was a Canadian research and demonstration project that attempted to "make work pay" for long-term income assistance (IA) recipients by supplementing their earnings. The long-term goal of SSP was to get lone parents permanently off IA and into the paid labour...

Many studies have estimated the effect of taxes on taxable income. To account for nonlinear taxes these studies either use instrumental variables approaches that are not fully consistent, or impose strong functional form assumptions. None allow for general heterogeneity in preferences. In this...