Representation Learning And Exploration In Reinforcement Learning

Monday, February 22, 2021 - 11:30am to 12:30pm

Event Calendar Category

CSAIL

Speaker Name

Akshay Krishnamurthy

Affiliation

Microsoft Research

Join Zoom meeting

https://mit.zoom.us/j/94665448181

Abstract

We will discuss new provably efficient algorithms for reinforcement in rich observation environments with arbitrarily large state spaces. These algorithms operate by learning succinct representations of the environment, which they use in an exploration module to acquire new information. The first algorithm, called Homer, operates in a block MDP model and uses a contrastive learning objective to learn the representation. The second algorithm, called FLAMBE, operates in a much richer class of low-rank MDPs and is model-based. Finally, Moffle is a model-free representation learning approach for low-rank MDPS. All algorithms accommodate nonlinear function approximation and enjoy the provable sample and computational efficiency guarantees.

 

Biography

Akshay Krishnamurthy is a principal researcher at Microsoft Research, New York City. Previously, he spent two years as an assistant professor in the College of Information and Computer Sciences at the University of Massachusetts, Amherst, and a year as a postdoctoral researcher at Microsoft Research, NYC. He completed his PhD in the Computer Science Department at Carnegie Mellon University, advised by Aarti Singh. His research interests are broadly in machine learning and statistics. More specifically, he is most excited about interactive learning, or learning settings that involve feedback-driven data collection. Recently his work has focused on decision-making problems with limited feedback, including contextual bandits and reinforcement learning.