2007): “Imperfect competition, integer constraints and industry dynamics,”International

Abstract: Amir and Lambson (2003) developed an in\u85nite-horizon, stochastic model of entry and exit by integer numbers of \u85rms facing sunk costs and uncertain market conditions. Here, as examples of the models usefulness, special cases are applied to the following three issues: (1) the relationship between sunk costs and industry concentration, (2) entry when current pro\u85ts are negative, and (3) the relationship between entry and the length of the product cycle