Contracts and Inequity Aversion

Inequity aversion is a special form of other regarding preferences and captures many features of reciprocal behavior, an apparently robust pattern in human nature. Using this concept we analyze the Moral Hazard problem and derive several results which differ from conventional contract theory. Our three key insights are: First, inequity aversion plays a crucial role in the design of optimal contracts. Second, there is a strong tendency towards linear sharing rules, giving a simple and plausible rationale for the prevalence of these schemes in the real world. Third, the Sufficient Statistics result no longer holds as optimal contracts may be ''too'' complete. Along with these key insights we derive a couple of further results.