Below is a selection of conferences in which I am or was involved in the organizing committee.

• General Chair for Hypertext 2016
• Program Chair for Hypertext 2014
• Poster and Demo Chair for Intelligent User Interfaces 2015
• Poster and Demo Chair for UMAP 2013
• Workshop and Tutorial Chair for UMAP 2012
• Publicity Chair for CHI 2012
• Publicity Chair for UMAP 2010 and UMAP 2011
• Co-organizer of several workshops at UMAP, ESWC and IUI
• Local Chair for Adaptive Hypermedia 2008
• Chair of the German workshop on Adaptivity and User modelling in Interactive Systems ABIS 2006, ABIS 2010 and ABIS 2012

Journal Reviewing

I am regularly invited to perform reviews for various scientific journals, among which:

• ACM Transactions on Interactive Intelligent Systems
• Journal of Web Semantics
• Multimedia Tools and Applications
• ACM Computing Surveys
• IEEE Transactions on Learning Technologies
• ACM Transactions on the Web

Program Committee Memberships (2015)

I have reviewed papers for a wide variety of conferences and workshops. A selection of conferences for which I served as a program committee member in 2015 is listed below.

• Hypertext 2015 - 26th ACM Conference on Hypertext and Social Media
• I-KNOW 2015 - 15th International Conference on Knowledge Technologies and Data-driven Business
• ICSLE 2015 - International Conference on Smart Learning Environments
• ICWL 2015 - The 14th International Conference on Web-based Learning
• IESD 2015 - 4th Intl. Workshop on INTELLIGENT EXPLORATION OF SEMANTIC DATA (IESD 2015)
• LAK 2015 - 5th International Conference on Learning Analytics & Knowledge
• LC 2015 - International Workshop on Learning in the Cloud
• mis4TEL'15 - 5th International Conference on Methodologies and Intelligent Systems for Tehnology Enhanced Learning
• MSM2015 - 6th International Workshop on Modeling Social Media
• SEMANTiCS 2015 - 11th International Conference on Semantic Systems
• SPS2015 - International Workshop on Social Personalisation & Search
• UMAP 2015 - 23rd Conference on User Modelling, Adaptation and Personalization
• VISLA15 - Visual approaches to learning analytics
• Mensch und Computer 2015