Exporting involves sunk costs, so some firms export while others do not. This proposition derives from a number of models of firm behaviour and has been exposed to microeconometric analysis. Evidence from the latter suggests that exporting firms are generally more productive than non-exporters;...

China's policy of encouraging export processing has been the topic of much discussion in the academic literature and policy debate. We use a recently developed econometric approach that allows for time varying "treatments" and estimate economically and statistically significant positive causal...