We study both endogenous and exogenous peer effects in worker productivity using an explicit network approach. We apply this method to data from an in-house call center of a multinational mobile network operator that include detailed information on individual performance. We find that a 10%...

We study both endogenous and exogenous peer effects in worker productivity using an explicit network approach. We find that a 10% increase in average co-worker current productivity increases worker productivity by 5.3%. A 10% increase in average co-worker permanent productivity decreases worker...

We study how friendship shapes students' political opinions in a natural experiment. We use the indicator whether two students were exogenously assigned to a short-term \integration group", unrelated to scholar activities and dissolved before the school year, as instrumental variable for their...