Time: 1:30pm Tuesday, 15th March.
Location: SIT 459
Speaker: Nicholas Mattei, Data61/UNSW
Title: A Novel Strategyproof Peer Selection Mechanism
There are many important settings where a group of agents want to select some subset of themselves, crowdsourcing the selection. For example, scientists might want to select some subset to fund, or a community might want to select a committee to oversee local projects. We make three contributions to such peer selection problems. First, we propose a new mechanism with good normative properties. It is, most importantly, strategyproof as agents have no incentive to misreport their sincere preferences. Second, we provide the first evaluation of this and other peer selection mechanisms proposed recently in the literature. The experiments use parameters derived from real world domains. Our new mechanism performs better both on average, and in the worst case, than other existing mechanisms. Third, our peer selection mechanism uses a randomized rounding step which is of value in its own right to solve the well known apportionment problem. In parliamentary and other settings where we wish to achieve proportional representation, we may have to round a group’s size up or down to the nearest exact integer. Our randomized rounding step offers a solution to such apportionment problems with both good normative and computational properties.
Nicholas Mattei is senior researcher working with Prof. Toby Walsh in the Decision Sciences group at Data61 (formerly known as the Optimisation Group at NICTA). He is also an adjunct lecturer in the School of Computer Science and Engineering (CSE) and member of the Algorithms Group at the University of New South Wales. His research focuses on computational aspects of social choice, preference aggregation, and assignment; using computation to enable and augment human decision making. Along with Prof. Toby Walsh, he is the founder and maintainer of PrefLib: A Library for Preferences. He previously worked as a programmer and embedded electronics designer for nano-satellites at NASA Ames Research Center. He received his Ph.D from the University of Kentucky under the supervision of Prof. Judy Goldsmith in 2012.