Implementing performance pay requires that workers' output be measured. When measurement costs differ among firms, those with a measurement cost advantage choose to implement performance pay. They attract the best workers, and both the level and variability of compensation are higher at these...

This paper reviews some of the most popular policy evaluation methods in empirical microeconomics: social experiments, natural experiments, matching, instrumental variables, discontinuity design, and control functions. It discusses identification of traditionally used average parameters and more...

"This paper examines the properties of instrumental variables (IV) applied to models with essential heterogeneity, that is, models where responses to interventions are heterogeneous and agents adopt treatments (participate in programs) with at least partial knowledge of their idiosyncratic...