In developing countries, labour supply and activity choices are distorted by the existence of labour market imperfections restricting entry to the activity sectors or rationing the worked hours. The presence of decreasing returns to labour in the informal sector is another specific...

Most of the data available to economists is observational rather than the outcome of natural or quasi experiments. This complicates analysis because it is common for observationally distinct individuals to exhibit similar responses to a given environment and for observationally identical...