This chapter discusses a wide range of strategies that can be employed by incumbent firms either to protect or to extend their market shares against competitive attacks by actual and potential entrants. The hallmark of these strategies is that, invariably, they reduce the expected level of...

This paper seeks to explain why monopolies keep their nominal prices constant for longer periods than do tight oligopolies. We provide two possible explanations. The first is based on the presence of a small fixed cost of changing prices. The second, on small costs of discovering the optimal...

This paper seeks to explain why monopolies keep their nominal prices constant for longer periods than do tight oligopolies. We provide two possible explanations. The first is based on the presence of a small fixed cost of changing prices. The second, on small costs of discovering the optimal...