IEOR seminars occur on Mondays throughout the fall semester in room 3108 of Etcheverry Hall. Seminars feature leading-edge research from experts in industrial engineering and operations research who come from local, national, and international institutions. Seminars are open to students, faculty, and the public.

Title: The strong maximum circulation problem: a new way of aggregating preferences.
Abstract: We present a new optimization-based method for aggregating preferences in settings where each decision maker, or voter, expresses preferences over pairs of alternatives. The challenge is to come up with a ranking that agrees as much as possible with the votes cast in cases when some of the votes conflict. Only a collection of votes that contains no cycles is non-conflicting and can induce a partial order over alternatives. Our approach is motivated by the observation that a collection of votes that form a cycle can be treated as ties. The method is then to remove unions of cycles of votes, or circulations, from the vote graph and determine aggregate preferences from the remainder. Further our method guarantees a unique outcome in terms of the induced partial order. In contrast, the well-known, optimization-based, Kemeny method has non-unique output and can return multiple, conflicting optimal rankings for the same input. In addition, Kemeny’s method requires solving an NP-hard problem, whereas our algorithm is efficient, based on network flow techniques, and runs in strongly polynomial time, independent of the number of votes.

Joint with Nathan Atkinson, Scott Ganz, and Dorit Hochbaum

Bio: James Orlin is the E. Pennell Brooks Professor of Operations Research at the MIT Sloan School. He is best known for his research on obtaining faster
algorithms for problems in network and combinatorial optimization and for
his text with Ravi Ahuja and Tom Magnanti entitled Network Flows: Theory,
Algorithms, and Applications.

He has won various awards for his co-authored publications: the 1993
Lanchester Prize for the best publication in O.R , the 2007 INFORMS
Computing Society Prize for research in the interface of O.R. and computer
science, the 2008 IEEE Leonard G. Abraham Prize for research in
communication theory, the 2011 IEEE Bennett Prize for research in
communication theory, the 2016 ACM SIGecom Test of Time Award, for a
paper published between 10 and 25 years ago that has had “significant
impact on research or applications that exemplify the interplay of economics
and computation,” and the 2020 Khachyian prize for lifetime achievements
in the area of optimization.

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Location: 3108 of Etcheverry Hall

November 13 @ 3:30 pm – 4:45 pm