Dominik Benz
Hinweis: Dominik Benz ist seit dem 31.10.2012 nicht mehr im Fachgebiet beschäftigt. [PGP key]

About me

I studied Computer Science with minor Psychology at the University of Freiburg. In May 2007, I joined the Knowledge and Data Engineering team in Kassel. I’m a senior developer of BibSonomy, and my scientific interests lie in the field of bridging the gap between the Social and the Semantic Web. In my dissertation, I analyzed methods to capture emergent semantics from social annotation systems.

Among others, my research in collaboration with several great colleagues has provided insight in the following areas:


Most courses I have been teaching or assisisting were held in German.

Lectures, Seminars

Supervised Theses

  • Automatische Webdokumentenklassifikation zur Unterstützung einer facettierten Suchmaschine an der Universität Kassel (Marek Bachmann)
  • Effiziente Analyse von Faktoren entstehender Semantik in Folksonomien (Tobias Gunkel)
  • Lernen von Ontologien aus kollaborativen Tagging-Systemen (Stefan Stützer)


Here you find a summary of my scientific activities related to conferences, workshops and journals.


My research is focussed around supporting users during knowledge interaction tasks like retrieval, structuring and collaboration. I am especially interested in Data Mining methods to discover latent Semantic information, e.g. in Social annotation data (e.g. from Tagging Systems). I see Ontology Learning approaches as a viable tools to bridge the gap between the Social and the Semantic Web.

Grants, Awards

Invited Talks

  • Literature Databases: Techniques and Tutorial (02/2005) Lab-Seminar, Department of Biology III, Freiburg (Prof. Ad Aertsen)
  • Self-emerging Semantics from Social Metadata: Factors, Methods and Evaluations of “Taxonomies made by you and me” (02/2011), Competence Center Information Retrieval & Machine Learning, DAI-Labors, TU Berlin (Dr. Ernesto William de Luca)
  • Web 2.0 ? Hype or Revolution for Researchers? (11/2011), International Congress on Communicating Life Science and Technology, Stra?urg (COMM4BIOTECH)

PhD summary

Title: Capturing Emergent Semantics from Social Annotation Systems

The ongoing growth of the World Wide Web, catalyzed by the increasing possibility of ubiquitous access via a variety of devices, continues to strengthen its role as our prevalent information and commmunication medium. The vision of supporting both humans and machines in knowledge-based activities led to the development of different systems which allow to structure Web resources by metadata annotations. Interestingly, two major approaches which gained a considerable amount of attention are addressing the problem from nearly opposite directions: On the one hand, the idea of the Semantic Web suggests to formalize the knowledge within a particular domain by means of a “top-down” approach of defining ontologies. On the other hand, Social Annotation systems as part of the so-called Web 2.0 movement implement a “bottom-up” style of categorization using arbitrary keywords.

Experience as well as research in the characteristics of both systems has shown that their strengths and weaknesses seem to be inverse: While Social Annotation suffers from problems like, e.g. ambiguity or lack or precision, ontologies were especially designed to eliminate those. On the contrary, the latter suffer from a knowledge acquisition bottleneck, which is successfully overcome by the large user populations of Social Annotation systems. Instead of being regarded as competing paradigms, the obvious potential synergies from a combination of both motivated approaches to “bridge the gap” between them. Those were fostered by the evidence of emergent semantics, i.e. the self-organized evolution of implicit conceptual structures, within Social Annotation data. While several techniques to exploit the emergent patterns were proposed, a systematic analysis — especially regarding paradigms from the field of ontology learning — is still largely missing. This also includes a deeper understanding of the circumstances which affect the evolution processes.

This work aims to address this gap by providing an in-depth study of methods and influencing factors to capture emergent semantics from Social Annotation Systems. We focus hereby on the acquisition of lexical semantics from the underlying networks of keywords, users and resources. Structured along different ontology learning tasks, we use a methodology of semantic grounding to characterize and evaluate the semantic relations captured by different methods. In all cases, our studies are based on datasets from several Social Annotation Systems.

Finally, we discuss a set of applications which operationalize our results for enhancing both Social Annotation and semantic systems. In summary, the contributions of this work highlight viable methods and crucial aspects for designing enhanced knowledge-based services of a Social Semantic Web.


During my PhD, I have been involved in the following research, industry and software projects:

Research Projects

Industry projects

  • Semantic Analysis of Keywords used in an internal Knowledge Base (K+S IT-Services GmbH, since 2011)

Software Projects


I participate in several Social Platforms – here you can find my latest activities.

BibSonomy bookmarks

BibSonomy publications

SlideShare presentations



Around my professional activities, I’m engaged at a number of projects and events I find more than worth to be supported:

  • Java User Group Nordhessen
    There’s no better source for Java expertise and networking around Kassel.
  • Eclipse Demo Camps
    Always stay up-to-date around my favourite IDE.
  • Freiwillig in Kassel
    Voluntary work in Kassel – great projects, especially during a “volunteer day”.
  • Wintersause
    Best student get-together in Kassel, in January – don’t miss the next event with live bands, DJs and more!
  • Tag der Technik
    “Day of Technical Jobs” – pupils can visit different parts of the University at this day and get an impression of what’s going on there.
  • Sommercampus Freiburg
    Sometimes people are complaining that not enough techical skills are being teached at Universities. The “Sommercampus” is a great initiative in Freiburg, where technical courses are offered by students and University staff to counterbalance this issue.
  • ESG Kassel
    I’ve offered a guitar course at the ESG – great team!



    • Evaluation of Folksonomy Induction Algorithms. Strohmaier, Markus; Helic, Denis; Benz, Dominik; Körner, Christian; Kern, Roman (2012).
      BibTeX EndNote URL


    • One Tag to Bind Them All : Measuring Term Abstractness in Social Metadata. Benz, Dominik; Körner, Christian; Hotho, Andreas; Stumme, Gerd; Strohmaier, Markus G. Antoniou, Grobelnik, M., Simperl, E., Parsia, B., Plexousakis, D., Pan, J., Leenheer, P. D. (eds.) (2011).
      BibTeX EndNote URL
    • Community Assessment using Evidence Networks. Mitzlaff, Folke; Atzmueller, Martin; Benz, Dominik; Hotho, Andreas; Stumme, Gerd in LNAI (2011). (Vol. 6904)
      BibTeX EndNote URL
    • Enhancing Social Interactions at Conferences. Atzmueller, Martin; Benz, Dominik; Doerfel, Stephan; Hotho, Andreas; Jäschke, Robert; Macek, Bjoern Elmar; Mitzlaff, Folke; Scholz, Christoph; Stumme, Gerd (2011). 53(3) 101--107.
      BibTeX EndNote URL
    • Towards Mining Semantic Maturity in Social Bookmarking Systems. Atzmüller, Martin; Benz, Dominik; Hotho, Andreas; Stumme, Gerd A. Passant, Fernández, S., Breslin, J., Bojārs, U. (eds.) (2011).
      BibTeX EndNote URL


    • Academic Publication Management with PUMA - collect, organize and share publications. Benz, Dominik; Hotho, Andreas; Jäschke, Robert; Stumme, Gerd; Halle, Axel; Lima, Angela Gerlach Sanches; Steenweg, Helge; Stefani, Sven in Lecture Notes in Computer Science, M. Lalmas, Jose, J., Rauber, A., Sebastiani, F., Frommholz, I. (eds.) (2010). (Vol. 6273) 417--420.
      BibTeX EndNote URL
    • Proceedings of the LWA 2010 - Lernen, Wissen, Adaptivität Atzmueller, Martin; Benz, Dominik; Hotho, Andreas; Stumme, Gerd in Technical report (KIS), 2010-10 (2010). Department of Electrical Engineering/Computer Science, Kassel University.
      BibTeX EndNote URL
    • Community Assessment using Evidence Networks. Mitzlaff, Folke; Atzmüller, Martin; Benz, Dominik; Hotho, Andreas; Stumme, Gerd (2010).
      BibTeX EndNote URL
    • Stop Thinking, start Tagging - Tag Semantics emerge from Collaborative Verbosity. Körner, Christian; Benz, Dominik; Strohmaier, Markus; Hotho, Andreas; Stumme, Gerd (2010).
      BibTeX EndNote URL
    • Query Logs as Folksonomies. Benz, Dominik; Hotho, Andreas; Jäschke, Robert; Krause, Beate; Stumme, Gerd (2010). 10(1) 15--24.
      BibTeX EndNote URL
    • Semantics made by you and me: Self-emerging ontologies can capture the diversity of shared knowledge. Benz, Dominik; Hotho, Andreas; Stützer, Stefan; Stumme, Gerd (2010).
      BibTeX EndNote URL
    • The social bookmark and publication management system bibsonomy. Benz, Dominik; Hotho, Andreas; Jäschke, Robert; Krause, Beate; Mitzlaff, Folke; Schmitz, Christoph; Stumme, Gerd (2010). 19(6) 849-875.
      BibTeX EndNote URL
    • Social Bookmarking Systems: Verbosity Improves Semantics. Körner, Christian; Benz, Dominik; Hotho, Andreas; Strohmaier, Markus; Stumme, Gerd (2010).
      BibTeX EndNote URL
    • Visit me, click me, be my friend: An analysis of evidence networks of user relationships in Bibsonomy. Mitzlaff, Folke; Benz, Dominik; Stumme, Gerd; Hotho, Andreas (2010).
      BibTeX EndNote URL


    • Evaluating Similarity Measures for Emergent Semantics of Social Tagging. Markines, Benjamin; Cattuto, Ciro; Menczer, Filippo; Benz, Dominik; Hotho, Andreas; Stumme, Gerd (2009). 641--641.
      BibTeX EndNote URL
    • Managing publications and bookmarks with BibSonomy. Benz, Dominik; Eisterlehner, Folke; Hotho, Andreas; Jäschke, Robert; Krause, Beate; Stumme, Gerd C. Cattuto, Ruffo, G., Menczer, F. (eds.) (2009). 323--324.
      BibTeX EndNote URL
    • Social Bookmarking am Beispiel BibSonomy. Hotho, Andreas; Jäschke, Robert; Benz, Dominik; Grahl, Miranda; Krause, Beate; Schmitz, Christoph; Stumme, Gerd A. Blumauer, Pellegrini, T. (eds.) (2009). 363--391.
      BibTeX EndNote URL
    • Characterizing Semantic Relatedness of Search Query Terms. Benz, Dominik; Krause, Beate; Kumar, G. Praveen; Hotho, Andreas; Stumme, Gerd (2009).
      BibTeX EndNote URL


    • Semantic Grounding of Tag Relatedness in Social Bookmarking Systems. Cattuto, Ciro; Benz, Dominik; Hotho, Andreas; Stumme, Gerd in LNAI, A. P. Sheth, Staab, S., Dean, M., Paolucci, M., Maynard, D., Finin, T. W., Thirunarayan, K. (eds.) (2008). (Vol. 5318) 615--631.
      BibTeX EndNote URL
    • Semantic Analysis of Tag Similarity Measures in Collaborative Tagging Systems. Cattuto, Ciro; Benz, Dominik; Hotho, Andreas; Stumme, Gerd (2008). 39--43.
      BibTeX EndNote URL
    • Evaluation Strategies for Learning Algorithms of Hierarchical Structures. Bade, Korinna; Benz, Dominik in Studies in Classification, Data Analysis, and Knowledge Organization (2008).
      BibTeX EndNote URL
    • Analyzing Tag Semantics Across Collaborative Tagging Systems. Benz, Dominik; Grobelnik, Marko; Hotho, Andreas; Jäschke, Robert; Mladenic, Dunja; Servedio, Vito D. P.; Sizov, Sergej; Szomszor, Martin H. Alani, Staab, S., Stumme, G. (eds.) (2008).
      BibTeX EndNote URL
    • ECML PKDD Discovery Challenge 2008 (RSDC'08) Hotho, Andreas; Benz, Dominik; Jäschke, Robert; Krause, Beate (2008). Workshop at 18th Europ. Conf. on Machine Learning (ECML'08) / 11th Europ. Conf. on Principles and Practice of Knowledge Discovery in Databases (PKDD'08).
      BibTeX EndNote URL


    • Supporting Collaborative Hierarchical Classification: Bookmarks as an Example. Benz, Dominik; Tso, Karen H. L.; Schmidt-Thieme, Lars (2007). 51(16) 4574--4585.
      BibTeX EndNote URL
    • Position Paper: Ontology Learning from Folksonomies. Benz, Dominik; Hotho, Andreas A. Hinneburg (ed.) (2007). 109--112.
      BibTeX EndNote URL
    • Interactive Thesaurus Assessment for Automatic Document Annotation. Eckert, Kai; Stuckenschmidt, Heiner; Pfeffer, Magnus (2007).
      BibTeX EndNote URL


    • Automatic Bookmark Classification - A Collaborative Approach. Benz, Dominik; Tso, Karen H. L.; Schmidt-Thieme, Lars (2006).
      BibTeX EndNote URL