Designing a Recommender System for Touristic Activities in a Big Data as a Service Platform.- A Scalable, Transparent Meta-Learning Paradigm for Big Data Applications.- Towards Addressing the Limitations of Educational Policy based on International Large-scale Assessment Data with Castoriadean Magmas.- What do Prospective Students Want? An Observational Study of Preferences About Subject of Study in Higher Education.- Speech Pause Patterns in Collaborative Dialogs.