TY - CONF AU - Benz, Dominik AU - Hotho, Andreas AU - Stützer, Stefan AU - Stumme, Gerd A2 - T1 - Semantics made by you and me: Self-emerging ontologies can capture the diversity of shared knowledge T2 - Proceedings of the 2nd Web Science Conference (WebSci10) PB - C1 - Raleigh, NC, USA PY - 2010/ CY - VL - IS - SP - EP - UR - http://www.kde.cs.uni-kassel.de/pub/pdf/benz2010semantics.pdf DO - KW - 2010 KW - ibm-kde-tagging KW - itegpub KW - myown KW - ol_web2.0 KW - semantics KW - web_science KW - websci KW - websci10 L1 - SN - N1 - N1 - AB - ER - TY - CHAP AU - Doush, Iyad Abu AU - Pontelli, Enrico A2 - Miesenberger, Klaus A2 - Klaus, Joachim A2 - Zagler, Wolfgang A2 - Karshmer, Arthur T1 - Integrating Semantic Web and Folksonomies to Improve E-Learning Accessibility T2 - Computers Helping People with Special Needs PB - Springer Berlin / Heidelberg C1 - PY - 2010/ VL - 6179 IS - SP - 376 EP - 383 UR - http://dx.doi.org/10.1007/978-3-642-14097-6_60 DO - KW - application KW - e-learning KW - ol_web2.0 L1 - SN - N1 - N1 - AB - ER - TY - CONF AU - Körner, Christian AU - Benz, Dominik AU - Strohmaier, Markus AU - Hotho, Andreas AU - Stumme, Gerd A2 - T1 - Stop Thinking, start Tagging - Tag Semantics emerge from Collaborative Verbosity T2 - Proceedings of the 19th International World Wide Web Conference (WWW 2010) PB - ACM C1 - Raleigh, NC, USA PY - 2010/04 CY - VL - IS - SP - EP - UR - http://www.kde.cs.uni-kassel.de/pub/pdf/koerner2010stop.pdf DO - KW - 2010 KW - collaborative_verbosity KW - emergentsemantics_factors KW - ibm-kde-tagging KW - itegpub KW - myown KW - ol_web2.0 KW - www KW - www2010 L1 - SN - N1 - N1 - AB - Recent research provides evidence for the presence of emergent semantics in collaborative tagging systems. While several methods have been proposed, little is known about the factors that influence the evolution of semantic structures in these systems. A natural hypothesis is that the quality of the emergent semantics depends on the pragmatics of tagging: Users with certain usage patterns might contribute more to the resulting semantics than others. In this work, we propose several measures which enable a pragmatic differentiation of taggers by their degree of contribution to emerging semantic structures. We distinguish between categorizers, who typically use a small set of tags as a replacement for hierarchical classification schemes, and describers, who are annotating resources with a wealth of freely associated, descriptive keywords. To study our hypothesis, we apply semantic similarity measures to 64 different partitions of a real-world and large-scale folksonomy containing different ratios of categorizers and describers. Our results not only show that ‘verbose’ taggers are most useful for the emergence of tag semantics, but also that a subset containing only 40% of the most ‘verbose’ taggers can produce results that match and even outperform the semantic precision obtained from the whole dataset. Moreover, the results suggest that there exists a causal link between the pragmatics of tagging and resulting emergent semantics. This work is relevant for designers and analysts of tagging systems interested (i) in fostering the semantic development of their platforms, (ii) in identifying users introducing “semantic noise??, and (iii) in learning ontologies. ER - TY - THES AU - Meder, Michael T1 - Multi-Domain Klassifikation basierend auf nutzergenerierten Metadaten PY - 2010/ PB - Technische Universität Berlin SP - EP - UR - DO - KW - ontology_learning KW - ol_web2.0 KW - thesis KW - berlin L1 - N1 - N1 - AB - ER - TY - CONF AU - Tatu, Marta AU - Moldovan, Dan I. A2 - Calzolari, Nicoletta A2 - Choukri, Khalid A2 - Maegaard, Bente A2 - Mariani, Joseph A2 - Odijk, Jan A2 - Piperidis, Stelios A2 - Rosner, Mike A2 - Tapias, Daniel T1 - Inducing Ontologies from Folksonomies using Natural Language Understanding. T2 - LREC PB - European Language Resources Association C1 - PY - 2010/ CY - VL - IS - SP - EP - UR - http://dblp.uni-trier.de/db/conf/lrec/lrec2010.html#TatuM10 DO - KW - ol_web2.0 L1 - SN - 2-9517408-6-7 N1 - N1 - AB - ER - TY - JOUR AU - Weichselbraun, Albert AU - Wohlgenannt, Gerhard AU - Scharl, Arno T1 - Augmenting Lightweight Domain Ontologies with Social Evidence Sources JO - Database and Expert Systems Applications, International Workshop on PY - 2010/ VL - 0 IS - SP - 193 EP - 197 UR - http://www.computer.org/portal/web/csdl/doi/10.1109/DEXA.2010.53 DO - 10.1109/DEXA.2010.53 KW - ol_web2.0 L1 - SN - N1 - Augmenting Lightweight Domain Ontologies with Social Evidence Sources N1 - AB - ER - TY - CONF AU - Barla, Michal AU - Bielikov�, M�ria A2 - Nguyen, Ngoc Thanh A2 - Kowalczyk, Ryszard A2 - Chen, Shyi-Ming T1 - On Deriving Tagsonomies: Keyword Relations Coming from Crowd. T2 - Computational Collective Intelligence. Semantic Web, Social Networks and Multiagent System PB - Springer C1 - PY - 2009/ CY - VL - 5796 IS - SP - 309 EP - 320 UR - http://dx.doi.org/10.1007/978-3-642-04441-0_27 DO - KW - ol_web2.0 KW - toread L1 - SN - 978-3-642-04440-3 N1 - N1 - AB - ER - TY - CONF AU - Benz, Dominik AU - Krause, Beate AU - Kumar, G. Praveen AU - Hotho, Andreas AU - Stumme, Gerd A2 - T1 - Characterizing Semantic Relatedness of Search Query Terms T2 - Proceedings of the 1st Workshop on Explorative Analytics of Information Networks (EIN2009) PB - C1 - Bled, Slovenia PY - 2009/10 CY - VL - IS - SP - EP - UR - http://www.kde.cs.uni-kassel.de/pub/pdf/benz2009characterizing.pdf DO - KW - 2009 KW - ecml_pkdd KW - ein KW - itegpub KW - logsonomies KW - myown KW - ol_web2.0 KW - similarity_measures KW - widely_related KW - workshop L1 - SN - N1 - N1 - AB - ER - TY - JOUR AU - Lehmann, Jens AU - Bizer, Chris AU - Kobilarov, Georgi AU - Auer, Sören AU - Becker, Christian AU - Cyganiak, Richard AU - Hellmann, Sebastian T1 - DBpedia - A Crystallization Point for the Web of Data JO - Journal of Web Semantics PY - 2009/ VL - 7 IS - 3 SP - 154 EP - 165 UR - http://jens-lehmann.org/files/2009/dbpedia_jws.pdf DO - doi:10.1016/j.websem.2009.07.002 KW - ol_web2.0 L1 - SN - N1 - publications Jens Lehmann N1 - AB - ER - TY - CONF AU - Markines, Benjamin AU - Cattuto, Ciro AU - Menczer, Filippo AU - Benz, Dominik AU - Hotho, Andreas AU - Stumme, Gerd A2 - T1 - Evaluating Similarity Measures for Emergent Semantics of Social Tagging T2 - 18th International World Wide Web Conference PB - C1 - PY - 2009/04 CY - VL - IS - SP - 641 EP - 641 UR - http://www.kde.cs.uni-kassel.de/pub/pdf/markines2009evaluating.pdf DO - KW - 2009 KW - itegpub KW - methods_concepts KW - myown KW - ol_web2.0 KW - semantic_relatedness KW - social_similarity KW - tagorapub KW - www2009 L1 - SN - N1 - N1 - AB - Social bookmarking systems and their emergent information structures, known as folksonomies, are increasingly important data sources for Semantic Web applications. A key question for harvesting semantics from these systems is how to extend and adapt traditional notions of similarity to folksonomies, and which measures are best suited for applications such as navigation support, semantic search, and ontology learning. Here we build an evaluation framework to compare various general folksonomy-based similarity measures derived from established information-theoretic, statistical, and practical measures. Our framework deals generally and symmetrically with users, tags, and resources. For evaluation purposes we focus on similarity among tags and resources, considering different ways to aggregate annotations across users. After comparing how tag similarity measures predict user-created tag relations, we provide an external grounding by user-validated semantic proxies based on WordNet and the Open Directory. We also investigate the issue of scalability. We ?nd that mutual information with distributional micro-aggregation across users yields the highest accuracy, but is not scalable; per-user projection with collaborative aggregation provides the best scalable approach via incremental computations. The results are consistent across resource and tag similarity. ER - TY - CONF AU - Angeletou, Sofia AU - Sabou, Marta AU - Motta, Enrico A2 - T1 - Semantically enriching folksonomies with FLOR T2 - Proceedings of the CISWeb Workshop, located at the 5th European Semantic Web Conference ESWC 2008 PB - C1 - PY - 2008/ CY - VL - IS - SP - EP - UR - http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.141.2569 DO - KW - ol_web2.0 KW - ontology_learning KW - semantic_enrichment L1 - SN - N1 - Scientific Commons: Semantically enriching folksonomies with FLOR (2008), 2008 [Sofia Angeletou, Marta Sabou, Enrico Motta] N1 - AB - Abstract. While the increasing popularity of folksonomies has lead to a vast quantity of tagged data, resource retrieval in folksonomies is limited by being agnostic to the meaning (i.e., semantics) of tags. Our goal is to automatically enrich folksonomy tags (and implicitly the related resources) with formal semantics by associating them to relevant concepts defined in online ontologies. We introduce FLOR, a method that performs automatic folksonomy enrichment by combining knowledge from WordNet and online available ontologies. Experimentally testing FLOR, we found that it correctly enriched 72 % of 250 Flickr photos. 1 ER - TY - CONF AU - Bade, Korinna AU - Benz, Dominik A2 - T1 - Evaluation Strategies for Learning Algorithms of Hierarchical Structures T2 - Proceedings of the 32nd Annual Conference of the German Classification Society - Advances in Data Analysis, Data Handling and Business Intelligence (GfKl 2008) PB - Springer C1 - Berlin-Heidelberg PY - 2008/ CY - VL - IS - SP - EP - UR - http://www.kde.cs.uni-kassel.de/pub/pdf/bade2008evaluation.pdf DO - KW - 2008 KW - evaluation_strategies KW - hiearchies KW - itegpub KW - myown KW - ol_web2.0 KW - widely_related L1 - SN - N1 - N1 - AB - Several learning tasks comprise hierarchies. Comparison with a "goldstandard" is often performed to evaluate the quality of a learned hierarchy. We assembled various similarity metrics that have been proposed in different disciplines and compared them in a unified interdisciplinary framework for hierarchical evaluation which is based on the distinction of three fundamental dimensions. Identifying deficiencies for measuring structural similarity, we suggest three new measures for this purpose, either extending existing ones or based on new ideas. Experiments with an artificial dataset were performed to compare the different measures. As shown by our results, the measures vary greatly in their properties. ER - TY - CONF AU - Benz, Dominik AU - Grobelnik, Marko AU - Hotho, Andreas AU - Jäschke, Robert AU - Mladenic, Dunja AU - Servedio, Vito D. P. AU - Sizov, Sergej AU - Szomszor, Martin A2 - Alani, Harith A2 - Staab, Steffen A2 - Stumme, Gerd T1 - Analyzing Tag Semantics Across Collaborative Tagging Systems T2 - Proceedings of the Dagstuhl Seminar on Social Web Communities PB - C1 - PY - 2008/ CY - VL - IS - 08391 SP - EP - UR - http://www.kde.cs.uni-kassel.de/pub/pdf/benz2008analyzing.pdf DO - KW - 2008 KW - dagstuhl KW - iin2009 KW - itegpub KW - myown KW - ol_web2.0 KW - tag_semantics KW - tagorapub KW - widely_related L1 - SN - N1 - N1 - AB - The objective of our group was to exploit state-of-the-art Information Retrieval methods for finding associations and dependencies between tags, capturing and representing differences in tagging behavior and vocabulary of various folksonomies, with the overall aim to better understand the semantics of tags and the tagging process. Therefore we analyze the semantic content of tags in the Flickr and Delicious folksonomies. We find that: tag context similarity leads to meaningful results in Flickr, despite its narrow folksonomy character; the comparison of tags across Flickr and Delicious shows little semantic overlap, being tags in Flickr associated more to visual aspects rather than technological as it seems to be in Delicious; there are regions in the tag-tag space, provided with the cosine similarity metric, that are characterized by high density; the order of tags inside a post has a semantic relevance. ER - TY - CONF AU - Cattuto, Ciro AU - Benz, Dominik AU - Hotho, Andreas AU - Stumme, Gerd A2 - T1 - Semantic Analysis of Tag Similarity Measures in Collaborative Tagging Systems T2 - Proceedings of the 3rd Workshop on Ontology Learning and Population (OLP3) PB - C1 - Patras, Greece PY - 2008/07 CY - VL - IS - SP - 39 EP - 43 UR - http://www.kde.cs.uni-kassel.de/pub/pdf/cattuto2008semantic.pdf DO - KW - 2008 KW - itegpub KW - methods_concepthierarchy KW - methods_concepts KW - myown KW - ol_web2.0 KW - olp3 KW - semantic_relatedness KW - tag_relatedness KW - tagorapub L1 - SN - 978-960-89282-6-8 N1 - N1 - AB - Social bookmarking systems allow users to organise collections of resources on the Web in a collaborative fashion. The increasing popularity of these systems as well as first insights into their emergent semantics have made them relevant to disciplines like knowledge extraction and ontology learning. The problem of devising methods to measure the semantic relatedness between tags and characterizing it semantically is still largely open. Here we analyze three measures of tag relatedness: tag co-occurrence, cosine similarity of co-occurrence distributions, and FolkRank, an adaptation of the PageRank algorithm to folksonomies. Each measure is computed on tags from a large-scale dataset crawled from the social bookmarking system del.icio.us. To provide a semantic grounding of our findings, a connection to WordNet (a semantic lexicon for the English language) is established by mapping tags into synonym sets of WordNet, and applying there well-known metrics of semantic similarity. Our results clearly expose different characteristics of the selected measures of relatedness, making them applicable to different subtasks of knowledge extraction such as synonym detection or discovery of concept hierarchies. ER - TY - CONF AU - Cattuto, Ciro AU - Benz, Dominik AU - Hotho, Andreas AU - Stumme, Gerd A2 - Sheth, Amit P. A2 - Staab, Steffen A2 - Dean, Mike A2 - Paolucci, Massimo A2 - Maynard, Diana A2 - Finin, Timothy W. A2 - Thirunarayan, Krishnaprasad T1 - Semantic Grounding of Tag Relatedness in Social Bookmarking Systems T2 - The Semantic Web -- ISWC 2008, Proc.Intl. Semantic Web Conference 2008 PB - Springer C1 - Heidelberg PY - 2008/ CY - VL - 5318 IS - SP - 615 EP - 631 UR - http://www.kde.cs.uni-kassel.de/pub/pdf/cattuto2008semantica.pdf DO - http://dx.doi.org/10.1007/978-3-540-88564-1_39 KW - 2008 KW - grounding KW - iswc2008 KW - itegpub KW - methods_concepthierarchy KW - methods_concepts KW - myown KW - ol_web2.0 KW - relatedness KW - semantic KW - semantic_relatedness KW - similarity KW - sw KW - tag KW - tagging KW - tagorapub L1 - SN - N1 - N1 - AB - Collaborative tagging systems have nowadays become important data sources for populating semantic web applications. For taskslike synonym detection and discovery of concept hierarchies, many researchers introduced measures of tag similarity. Eventhough most of these measures appear very natural, their design often seems to be rather ad hoc, and the underlying assumptionson the notion of similarity are not made explicit. A more systematic characterization and validation of tag similarity interms of formal representations of knowledge is still lacking. Here we address this issue and analyze several measures oftag similarity: Each measure is computed on data from the social bookmarking system del.icio.us and a semantic grounding isprovided by mapping pairs of similar tags in the folksonomy to pairs of synsets in Wordnet, where we use validated measuresof semantic distance to characterize the semantic relation between the mapped tags. This exposes important features of theinvestigated similarity measures and indicates which ones are better suited in the context of a given semantic application. ER - TY - JOUR AU - Levy, M. AU - Sandler, M. T1 - Learning latent semantic models for music from social tags JO - Journal of New Music Research PY - 2008/ VL - 37 IS - 2 SP - 137 EP - 150 UR - DO - KW - semantics KW - ol_web2.0 KW - music KW - tagging L1 - SN - N1 - N1 - AB - ER - TY - CONF AU - Benz, Dominik AU - Hotho, Andreas A2 - Hinneburg, Alexander T1 - Position Paper: Ontology Learning from Folksonomies T2 - Workshop Proceedings of Lernen - Wissensentdeckung - Adaptivität (LWA 2007) PB - Martin-Luther-Universität Halle-Wittenberg C1 - PY - 2007/10 CY - VL - IS - SP - 109 EP - 112 UR - http://www.kde.cs.uni-kassel.de/pub/pdf/benz2007position.pdf DO - KW - 2007 KW - diploma_thesis KW - ibm-kde-tagging KW - itegpub KW - methods_concepthierarchy KW - myown KW - ol_web2.0 KW - ontology_learning KW - rel1 KW - rel2 KW - tagorapub L1 - SN - 978-3-86010-907-6 N1 - N1 - AB - The emergence of collaborative tagging systems with their underlying flat and uncontrolled resource organization paradigm has led to a large number of research activities focussing on a formal description and analysis of the resulting “folksonomies??. An interesting outcome is that the characteristic qualities of these systems seem to be inverse to more traditional knowledge structuring approaches like taxonomies or ontologies: The latter provide rich and precise semantics, but suffer - amongst others - from a knowledge acquisition bottleneck. An important step towards exploiting the possible synergies by bridging the gap between both paradigms is the automatic extraction of relations between tags in a folksonomy. This position paper presents preliminary results of ongoing work to induce hierarchical relationships among tags by analyzing the aggregated data of collaborative tagging systems as a basis for an ontology learning procedure. ER - TY - CHAP AU - man Yeung, Ching AU - Gibbins, Nicholas AU - Shadbolt, Nigel A2 - Aberer, Karl A2 - Choi, Key-Sun A2 - Noy, Natasha A2 - Allemang, Dean A2 - Lee, Kyung-Il A2 - Nixon, Lyndon A2 - Golbeck, Jennifer A2 - Mika, Peter A2 - Maynard, Diana A2 - Mizoguchi, Riichiro A2 - Schreiber, Guus A2 - Cudré-Mauroux, Philippe T1 - Mutual Contextualization in Tripartite Graphs of Folksonomies T2 - The Semantic Web PB - Springer C1 - Berlin / Heidelberg PY - 2007/ VL - 4825 IS - SP - 966 EP - 970 UR - http://dx.doi.org/10.1007/978-3-540-76298-0_79 DO - 10.1007/978-3-540-76298-0_79 KW - context KW - folksonomies KW - ol_web2.0 KW - tagging L1 - SN - N1 - SpringerLink - Abstract N1 - AB - The use of tags to describe Web resources in a collaborative manner has experienced rising popularity among Web users in recent years. The product of such activity is given the name folksonomy, which can be considered as a scheme of organizing information in the users’ own way. This research work attempts to analyze tripartite graphs – graphs involving users, tags and resources – of folksonomies and discuss how these elements acquire their semantics through their associations with other elements, a process we call mutual contextualization. By studying such process, we try to identify solutions to problems such as tag disambiguation, retrieving documents of similar topics and discovering communities of users. This paper describes the basis of the research work, mentions work done so far and outlines future plans. ER - TY - CONF AU - Hotho, Andreas AU - Jäschke, Robert AU - Schmitz, Christoph AU - Stumme, Gerd A2 - Hochberger, Christian A2 - Liskowsky, Rüdiger T1 - Emergent Semantics in BibSonomy T2 - Informatik 2006 -- Informatik für Menschen. Band 2 PB - Gesellschaft für Informatik C1 - Bonn PY - 2006/october CY - VL - P-94 IS - SP - EP - UR - http://www.kde.cs.uni-kassel.de/stumme/papers/2006/hotho2006emergent.pdf DO - KW - 2006 KW - UniK KW - bibsonomy KW - emergence KW - emergent KW - emergentsemantics_evidence KW - folksonomy KW - hotho KW - itegpub KW - jaeschke KW - l3s KW - myown KW - nepomuk KW - ol_web2.0 KW - schmitz KW - semantics KW - stumme KW - tagorapub L1 - SN - N1 - N1 - AB - Social bookmark tools are rapidly emerging on the Web. In suchsystems users are setting up lightweight conceptual structurescalled folksonomies. The reason for their immediate success is thefact that no specific skills are needed for participating. In thispaper we specify a formal model for folksonomies, briefly describeour own system BibSonomy, which allows for sharing both bookmarks andpublication references, and discuss first steps towards emergent semantics. ER - TY - BOOK AU - Manning, C. AU - Schütze, H. A2 - T1 - Foundations of statistical natural language processing PB - MIT Press C1 - Cambridge, MA PY - 1999/ VL - IS - SP - EP - UR - DO - KW - nlp KW - ol_web2.0 L1 - SN - N1 - N1 - AB - ER -