Research interests: I am mainly interested in machine learning theory and pattern recognition. I have also some interest in function representation and approximation, numerical optimization and statistics. I have worked on different learning approaches, particularly on regularization methods, such as support vector machines and other kernel-based methods. Other topics of recent interest include multi-task and transfer learning, online learning and learning over graphs. I have also worked on machine learning applications arising in computer vision, natural language processing, bioinformatics and marketing research.