Featured event

SILO Seminar Series: Justin Khim & Aniruddha Bhargava

Event Details

When: November 30, 2016, 12:30 PM

Location: 3rd Floor Orchard View Room , Discovery Building

Contact: 608-316-4401, hstampfli@wisc.edu

Anirudda Bhargava

Anirudda Bhargava
Ph.D. Candidate
UW–Madison

Video: https://vimeo.com/195638161

Bandits meet Matrix Completion

The classical bandit problem assumes a fixed distribution of rewards over a set of arms. There’s been work done before to model multiple populations. Most of them rely on some form of clustering or classification using side information about the users. What if we don’t have side information?

In this work, we propose a new method that reformulates the multi-population bandit modeling as that of completing a symmetric positive semi-definite matrix. The results are in itself new in the area of active matrix completion of SPSD matrices. I will also present some simulation results on data modeled from human feedback.

Justin Khim Ph.D. Candidate UW–Madison

Justin Khim
Ph.D. Candidate
UW–Madison

Adversarial influence maximization

We consider the problem of influence maximization in fixed networks. The goal is to select a subset of nodes of a specified size to infect so that the number of infected nodes at the conclusion of the epidemic is as large as possible. We introduce an adversarial setting in which an adversary is allowed to specify the edges through which contagion may spread, and the player chooses sets of nodes to infect in successive rounds. We establish upper and lower bounds on the minimax pseudo-regret in both undirected and directed networks.


The weekly SILO seminar series is made possible through the generous support of the 3M Company and its Advanced Technology Group
SILO is a lecture series with speakers from the UW faculty, graduate students or invited researchers that discuss mathematical related topics. The seminars are organized by WID’s Optimization research group.
SILO’s purpose is to provide a forum that helps connect and recruit mathematically-minded graduate students. SILO is a lunch-and-listen format, where speakers present interesting math topics while the audience eats lunch.