We critically review the emerging literature in Organizational and Personnel Economics concerning the role of managers and management practices. Our focus is on the middle managers who populate the hierarchies between top executives and front-line employees. We are especially concerned with...

We survey the literature on social networks by putting together the economics, sociological and physics/applied mathematics approaches, showing their similarities and differences. We expose, in particular, the two main ways of modeling network formation. While the physics/applied mathematics...