His Ph.D., from the University of Massachusetts Amherst, focused on high-performance text retrieval systems that are easily adaptable to fit specific retrieval applications. He has published papers and presented a tutorial at the top information retrieval conference, SIGIR. He is the creator of the Galago search engine, and the primary developer of the Indri search engine (www.lemurproject.org/indri). He has ten years of professional software development experience, including desktop, server, and web applications.