Meryem Essaidi will present her General Exam on Tuesday, May 21, 2019 at 9:30am in CS 402. The members of her committee are: Matt Weinberg (adviser), Mark Braverman, Gillat Kol Everyone is invited to attend her talk, and those faculty wishing to remain for the oral exam following are welcome to do so. Her abstract and reading list follow below. Abstract: The Mechanism Design for Social Good group is a multi-institutional research group that uses different tools to solve crucial problems (e.g. US healthcare) that nowhere have near enough foundational tools, and that impact the historically under-served communities. These problems are unable to just "use Machine Learning" because every trial in trial-and-error costs billions/trillions of dollars. In this segment of work, we are trying to do foundational theory targeted at these applications aiming to improve the societal welfare of marginalized communities, starting with healthcare. We study a problem inspired by regulated health insurance markets, such as those created by the government in the Affordable Care Act Exchanges or by employers when they contract with private insurers provide plans for their employees. The market regulator (e.g. the government or employer in these examples) can choose to do nothing, running a Free Market, or can exercise her regulatory power, such as limiting the entry of the health insurance providers to create competition and decrease prices. In this paper, we investigate whether limiting entry increases or decreases the utility of the consumers who purchase from the providers, specifically in settings where the outside option of “purchasing nothing” is prohibitively undesirable (i.e. because of the Individual Mandate). We focus primarily on the case where providers are symmetric, and study the existence of unique symmetric equilibria. We precisely define the condition under which limiting entry improves consumer utility. Using Myersonian theory, we also suggest a new distributional condition that ensures the existence of a unique symmetric equilibrium and further we show that under this assumption, the Limit-Entry condition is implied, thus limiting entry always improves consumer utility. However, we also show examples in which there exist unique symmetric equilibria where consumer utility in the free market setting exceeds that in the limited entry setting. Our techniques are based primarily on tools from revenue maximization. We also include small extensions to settings where providers have identical costs for providing plans, and to two providers with an asymmetric distribution. Reading list: - Textbook: Twenty Lectures on Algorithmic Game Theory (by Roughgarden) - Optimal Auction Design (by Myerson) - Algorithms, Games, and the Internet (by Papadimitriou) - Stable Matchings, Optimal Assignments, and Linear Programming (by Roth, Rothblum, and Vate) - Optimal and Robust Mechanism Design with Interdependent Values (by Roughgarden and Cohen) - College Admissions and the Stability of Marriage (by Gale and Shapley) - Auctions Versus Negotiations (by Bulow and Klemperer) - Simple versus Optimal Mechanisms (by Hartline and Roughgarden) - Playing Large Games Using Simple Strategies (by Lipton, Markakis, and Mehta) - A Simple Mechanism for a Budget-Constrained Buyer (by Cheng, Gravin, Munagala, and Wang) - The Economics of Matching: Stability and Incentives (by Roth)