He also holds appointments in the Institute for Advanced Computer Studies (UMIACS) and the Department of Computer Science at Maryland. He joined the faculty in 2004, after completing his Ph.D. in Electrical Engineering and Computer Science at MIT. He works at the intersection of natural language processing (NLP) and information retrieval (IR), with a recent emphasis on scalable algorithm design and large-data issues. He directs the recently-formed Cloud Computing Center, an interdisciplinary group which explores the many aspects of cloud computing as it impacts technology, people, and society. He is also a member of both the Computational Linguistics and Information Processing Lab (CLIP) and the Human-Computer Interaction Lab (HCIL). He is currently spending his sabbatical at Twitter.