**Work****ing Papers**

**Work**

**ing Papers**

**Mechanism Design without Rational Expectations**

**Mechanism Design without Rational Expectations**

**Draft available upon request**

The Bayesian implementation literature has identified in Bayesian Incentive Compatibility (BIC) a key condition that a social choice rule has to satisfy to be fully implementable by a social planner. I propose a generalized model of implementation that does not assume rational expectations, and I characterize the class of solution concepts such that BIC is necessary for full implementation of functions. I find we can not expect significantly more permissive results by dropping the rational expectations assumption and moving to non-equilibrium models. Using the same conditions, I prove that some classical results (including Myerson and Satterthwaite’s impossibility of efficient bilateral trade) hold for a wide range of non-equilibrium solution concepts.

**Paper presentations:*** Boston College Graduate Reading Group, 12th Conference on Economic Design, 16th SSCW Meeting, University of Bologna (Internal Seminar, 2022), SING17, 33rd Stony Brook International Conference, 1st NSEF Worskhop.*

**Work in Progress**

**Work in Progress**

**Mechanism Design under Outcome Constraints**

**Mechanism Design under Outcome Constraints**

In the traditional implementation framework, it is assumed the planner has almost complete freedom in choosing the mechanism she will use to implement the social choice rule. I generalise the model by requiring the implementing mechanism to also satisfy some exogenously imposed constraints on the outcomes in each agent’s opportunity set. I discuss applications of this framework to mechanism design in network environments and to one-sided matching with priorities.

**Recommendations without Rational Expectations**

**Recommendations without Rational Expectations**