Iterative Versus Standard Deferred Acceptance : Experimental Evidence

We test experimentally the Gale-Shapley Deferred Acceptance (DA) mechanism versus two versions of the Iterative Deferred Acceptance Mechanism (IDAM), in which students make applications one at a time. A significantly higher proportion of stable outcomes is reached under IDAM than under DA. The difference can be explained by a higher proportion of subjects following an equilibrium truthful strategy under iterative mechanisms than the dominant strategy of truthful reporting under DA. We associate the benefits of iterative mechanisms with the feedback on the outcome of the previous application they provide to students between steps.