Are initial competitive advantages self-reinforcing, so that markets exhibit an endogenous tendency to be dominated by only a few firms? Although this question is of great economic importance, no systematic empirical study has yet addressed it. Therefore, we examine experimentally whether firms...

Economists have traditionally treated preferences as exogenously given. Preferences are assumed to be influenced by neither beliefs nor the constraints people face. As a consequence, changes in behaviour are explained exclusively in terms of changes in the set of feasible alternatives. Here we...