David is a Research Staff Member at the Information Retrieval group at IBM Haifa Research Lab. David's research is focused on search in the enterprise, query performance prediction, social search, and text mining. For several years David taught the Introduction to IR course at the CS department at Haifa university. At IBM, David is a key contributor to IBM enterprise search offerings. David is a co-founder of the Juru search engine which provides integrated search capabilities to several IBM products, and was used as a search platform for several studies in the TREC conferences. David has published more than 80 papers in IR and Web journals and conferences, and serves on the editorial board of the IR journal and as a senior PC member or an Area Chair of many conferences (SIGIR, WWW, WSDM. CIKM). He organized a number of workshops and taught several tutorials at SIGIR, and WWW. David is co-author of the book "Estimating the Query Difficulty for Information Retrieval", published by Morgan & Claypool in 2010, and the co-author of the paper "Learning to estimate query difficulty" who won the Best Paper Award at SIGIR 2005. David earned his PhD in Computer Science from the Technion, Israel Institute of Technology in 1997.