Causal inference is of central interests in many empirical applications yet often challenging because of the presence of endogenous regressors. The classical approach to the problem requires using instrumental variables that must satisfy the stringent condition of exclusion restriction. At the...

Conventional wisdom holds that illegal copies cannibalize legitimate sales, even though previous research has found mixed effects, with illegal copies acting as both a substitute and complement. Yet, a relatively unexamined aspect to date is the quality of illegal copies. Building on product...

Conventional wisdom holds that illegal copies cannibalize legitimate sales, even though previous research has found mixed effects, with illegal copies acting as both a substitute and complement. Yet, a relatively unexamined aspect to date is the quality of illegal copies. Building on product...