Hi, I’m Ioannis Arapakis, currently a Principal Research Scientist at Telefonica Research.

I hold a Ph.D. in Information Retrieval from the School of Computing Science of the University of Glasgow. My thesis addresses the offline and online modeling of user behaviour in the context of web search, and was supervised by Prof. Joemon M. Jose, Dr. Phil Gray, and Prof. C. J. Keith van Rijsbergen. I have also a M.Sc. degree in Information Technology (with specialisation in Interactive Systems Engineering) from the Royal Institute of Technology, under the supervision of Asst. Prof. Teresa Cerratto Pargman.

During the last four years I have worked as a Research Scientist at Yahoo Labs, where I conducted research in the areas of Data Mining, IR, and HCI. Over this period, I was an active member of the (1) User Engagement, (2) Web Retrieval and (3) Ad Processing and Retrieval groups, lead several internal projects (see Section “Research”), and addressed research problems related to pattern recognition, predictive modeling, multimedia mining and search, social media analysis, and machine learning (see Section “Publications”).

My diverse set of theoretical knowledge, technical skills, and industrial expertise, allows me to analyse, understand and model rich data repositories, and contribute to scientific innovation both in industry and society. My insatiable curiosity constantly reveals me to new and exciting knowledge domains and research problems, which I am always willing to explore.

Central to my research is the investigation of innovative behaviour interpretation algorithms and methods that can account for the contextual, personal and historical information of user activity, while drawing knowledge from data mining, machine learning and neuroscience. I am also interested in methods for leveraging knowledge inferred from biowearables and laboratory tests with the help of online behaviour metrics acquired through automatic, low-cost, and scalable techniques. My research interests include:

• Machine Learning: deep learning, reinforcement learning, predictive modelling, statistical inference, time series analysis
• Information Retrieval: multimedia search, recommender systems, ad retrieval, user modelling, evaluation and applications
• Human-Computer Interaction: experimental methods, user engagement, neuro-physiological signal processing, sentiment analysis