Altruists and envious people who meet in contests are symbionts. They do better than a population of narrowly rational individuals. If there are only altruists and envious individuals, a particular mixture of altruists and envious individuals is evolutionarily stable.

We consider dynamic competition among platforms in a market with network externalities. A platform that dominated the market in the previous period becomes "focal" in the current period, in that agents play the equilibrium in which they adopt the focal platform whenever such equilibrium exists....

firms compete in all-pay auctions with complete information, silent shareholdings introduce asymmetric externalities into the all-pay auction framework. If the strongest firm owns a large share in the second strongest firm, this may make the strongest firm abstain from bidding. As a consequence,...

Competition in some markets is a contest. This paper studies the merger incentives in such markets. Merger can be profitable. The profitability depends on the post-merger contest st ructure, the discriminatory power of the contest and on the number of contestants

We propose an analysis of platform competition based on the academic literature with a view towards competition policy. First, we discuss to which extent competition can emerge in digital markets and show which forms it can take. In particular, we underline the role of dynamics, but also of...

We study the implications of credit constraints for the sustainability of product market collusion in a bank-financed oligopoly in which firms face an imperfect credit market. We consider two situations, without and with credit rationing, i.e., with a binding credit limit. When there is credit...