In many situations the indivaduals who can generate some output must enter a contest for appropriating this output. This paper analyses the investment incentives of such agents and the role of incumbency advantages in the contest. Depending on the advantages, an increase in the productivity of...

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.