Isabella Peters
Folksonomies Indexing and Retrieval in Web 2.0
Translated from German by Paul Becker
De Gruyter • Saur Contents
Introduction ...... 1 Current State of Research ...... 5 Open Questions in Folksonomy Research ...... 6 Notes an the Book's Structure ...... 8 Bibliography ...... 10
Chapter 1 Collaborative Information Services ...... 13 Web 2.0 vs Social Software vs Collaborative Information Services ...... 13 Social Bookmarking Services ...... 23 E-Commerce ...... 37 Commercial Information Services ...... 45 Music-Sharing Services ...... 49 Libraries 2.0 — Museums ...... 55 Photosharing Services ...... 69 Videosharing Services ...... 80 Social Networks ...... 88 Blogs and Blog Search Engines ...... 96 Garnes with a Purpose (GWAP) — Tagging Garnes ...... 100 Summary...... 104 Bibliography ...... 107
Chapter 2 Basic Terms in Knowledge Representation and Information Retrieval ...... 119 Introduction to Knowledge Representation ...... 119 Paradigmatic and Syntagmatic Relations ...... 124 Ontologies ...... 124 Thesauri ...... 125 Classification Systems ...... 126 Nomenclatures ...... 128 Text-Word Method ...... 128 Citation Indexing ...... 128 Knowledge Representation in the World Wide Web ...... 129 Introduction to Information Retrieval ...... 130 Relevance Distributions ...... 131 Retrieval Models ...... 133 Text Statistics ...... 134 Vector Space Model ...... 135 Probabilistic Model ...... 136 Link Topology — Kleinberg Algorithm and PageRank ...... 138 Information Linguistics — NLP ...... 139 v C nt nt
Similarity Coefficients and Cluster Analysis...... 142 Network Model ...... 144 Bibliography ...... 146
Chapter 3 Knowledge Representation in Web 2.0: Folksonomies ...... 153 Definition of the Term `Folksonomy' ...... 153 Tags — Users — Resources ...... 157 Cognitive Skills ..... 161 Broad vs Narrow Folksonomies ...... 164 Collective Intelligence ..... 166 Tag Distributions ...... 170 Users' Tagging Behavior ...... 184 Tag Categories ...... 196 Tag Recommender Systems ...... 204 Advantages and Disadvantages of Folksonomies in Knowledge Representation ...... 212 Problem-Solving and Structuring Endeavors in Folksonomies ...... 228 Tag Gardening in Knowledge Representation ...... 235 Traditional Methods of Knowledge Representation vs Folksonomies ...... 247 Outlook ...... 255 Bibliography ...... 262
Chapter 4 Information Retrieval with Folksonomies ...... 283 The Relation between Knowledge Representation and Information Retrieval ...... 285 Searching vs Browsing vs Retrieving ...... 287 Information Filters — Information Filtering — Collaborative Filtering ...... 293 Folksonomy-Based Recommender Systems in Information Retrieval ...... 299 Retrieval Effectiveness of Folksonomies ...... 310 Visualizations of Folksonomies ...... 314 Disadvantages of Folksonomies in Information Retrieval ...... 332 Query Tags as Indexing Tags ...... 336 Relevance Ranking in Folksonomies ...... 339 Power Tags ...... 363 Tag Gardening in Information Retrieval ...... 372 Outlook ...... 388 Bibliography ...... 393
Conclusion ...... 411 Bibliography ...... 418
Index of Names ...... 419 Subject Index ...... 431