Emulation in Teams and Families

We present a model where the probability distribution over the space of an agent's achievements depends not only on her ability and eort, but also on the goals set for her (aka the intensity of her training program). The agent chooses her eort according to her utility net of perceived cost of eort.The principal incurs costs in setting goals, i. e. coaching the agent, and subtracts these costs from the maximand. The agent's perceived unit cost of eort is inversely proportional to an 'emulation function'that depends on the training undertaken by rival agents. In a situation where two principals separately attempt to motivate two rival agents we …nd a unique Nash equilibrium if each agent's ability exceeds the di¢ culty of training, both from the point of view of the agent's di¢ culty and the principal's. If not there may be no Nash equilibrium, or a stable-unstable pair. In the second half of the paper we turn our attention, not to teams, but ot families where parents have a more caring attitude than coaches. We show that in many circumstances the emulation process reverses our naive intuition. There are now two distinct ways of prodding children or athletes to success: direct coaching and emulation through sibling rivalry. It is not a pretty world! Acknowledgements: We thank participants to the McGill Eco- nomics seminar series and in particular Hassan Benchekroun for in- sightful comments, and Nathalie Bannier for precious technical assis- stance.