The principal-agent problem with smooth ambiguity

We study a principal-agent model in which the (effort-dependent) realisation of output levels is ambiguous, and the agent is ambiguity averse (while the principal is ambiguity neutral). We show that introducing ambiguity aversion will lower profits if the action that the principal wants to implement is the most ambiguous one, while they may increase otherwise. Regarding the design of the optimal contract, we show that under ambiguity aversion the optimal incentive scheme may not be monotone even if a natural generalization of the monotone likelihood ratio property is satisfied, and illustrate how this fact could affect the design of contracts in an applied economic context. We also find that the individual rationality constraint need not bind in the presence of ambiguity aversion unless preferences satisfy constant absolute ambiguity aversion.