We study Pareto efficient mechanisms in matching markets when the number of agents is large and individual preferences are randomly drawn from a class of distributions, allowing for both common and idiosyncratic shocks. We provide a broad set of circumstances under which, as the market grows...

We study Pareto efficient mechanisms in matching markets when the number of agents is large and individual preferences are randomly drawn from a class of distributions, allowing for both common and idiosyncratic shocks. We show that, as the market grows large, all Pareto efficient mechanisms --...

We investigate efficient and minimally unstable Pareto improvements over the deferred acceptance (DA) mechanism — a popular school choice mechanism which is stable but not efficient. We show that there is no Pareto improvement over the DA mechanism which is minimally unstable among efficient...

We investigate efficient and minimally unstable Pareto improvements over the deferred acceptance (DA) mechanism-a popular school choice mechanism that is stable but not efficient. We show that there is no Pareto improvement over the DA mechanism that is minimally unstable among efficient...

We introduce a new notion of ex-post efficiency for random assignment problems, namely ex-post rank efficiency that gives a maximal number of agents their favored objects. An ex-post rank efficient random assignment is a lottery over rank efficient deterministic assignments, in the sense of...

We introduce ex-ante Pareto efficiency, which is a slightly weaker notion of efficiency than ex-post Pareto efficiency. We strengthen the impossibility between ex-post Pareto efficiency, strategyproofness, and envy-freeness in the random assignment problem and show that it prevails if ex-post...