@inbook {hadzilacos2008developing, title = {On Developing and Communicating User Models for Distance Learning Based on Assignment and Exam Data}, booktitle = {Intelligent Interactive Systems in Knowledge-Based Environments}, year = {2008}, pages = {137{\textendash}155}, publisher = {Springer}, organization = {Springer}, author = {Hadzilacos, Thanasis and Kalles, Dimitris and Christos J. Pierrakeas} } @inbook {hadzilacos2006small, title = {On small data sets revealing big differences}, booktitle = {Advances in Artificial Intelligence}, year = {2006}, pages = {512{\textendash}515}, publisher = {Springer}, organization = {Springer}, author = {Hadzilacos, Thanasis and Kalles, Dimitris and Christos J. Pierrakeas and Xenos, Michalis} }