This book constitutes the thoroughly refereed post-workshop proceedings of the 5th International Workshop on Empathic Computing, IWEC 2014, co-loacted with PRICAI 2014, held in Gold Coast, QLD, Australia, in December 2014, as well as the 6th International Workshop on Empathic Computing, IWEC 2015, and the 15th Workshop on Computational Models of Natural Argument, CMNA XV, both co-located with PRIMA 2015, held in Bertinoro, Italy, in October 2015.

The 12 papers presented were carefully reviewed and selected from 32 initial submissions. The workshops are going alongside with the PRIMA 2015 Conference and are intended to facilitate active exchange, interaction and comparison of approaches, methods and various ideas in specific areas related to intelligent agent systems and multiagent systems.

Cognitive Approach to Relevant Argument Generation.- Argumentation Mining in Parliamentary Discourse.- Modelling Argumentative Behaviour in Parliamentary Debates: Data Collection, Analysis and Test Case.- Automatically Detecting Fallacies in System Safety Arguments.- Modeling User Music Preference through Usage Scoring and User Listening Behavior for Generating Preferred Playlists.- Neural Prediction of the User's Mood from Visual Input.- A Conversational Agent to Shift Students' Affect State.- Comparing Affect Recognition in Peaks and Onset of Laughter.- Modeling Work Stress Using Heart Rate and Stress Coping Profiles.- Wizard-of-Oz Support Using a Portable Dialogue Corpus.- Identifying Significant Task-Based Predictors of Emotion in Learning.- Design of Populations in Symbiotic Evolution to Generate Chord Progression in Consideration of the Entire Music Structure.- Item-Based Learning for Music Emotion Prediction Using EEG Data.