I am Head of Data Science at Lumi, Semion Ltd (www.lumi.do), a startup company by the founders of last.fm, that provides personalised recommendations of Web content to users based on interests discovered from their browsing history or Twitter streams. Before that, I worked as a research consultant at Microsoft Bing and at Microsoft Research. My background is in computer science with over 9 years of research experience in information retrieval (IR). My work focuses on user-oriented aspects of IR and personal information management (PIM), with influences from HCI. My research interests include recommender systems and their offline/online evaluation, crowdsourcing, IR evaluation, social IR, information seeking behaviour, activity based PIM, book search and personal digital libraries. My current focus is on crowdsourcing and search engine evaluation. I am one of the founders and organisers of the INEX Book Track since 2007 and the TREC Crowdsourcing track since 2011. I am currently working on a book “Crowdsourcing for Search Engine Evaluation” with Omar Alonso and Stefano Mizzaro. I hold a PhD in IR from Queen Mary University of London. My PhD work covered the evaluation of focused information retrieval approaches. I published over 90 papers and organized several workshops and an IR conference.