FaceTag: Integrating Bottom-up and Top-down Classification in a Social Tagging System

Slide 1: FaceTag Integrating Bottom-up and Top-down Classification in a Social Tagging System Emanuele Quintarelli, Andrea Resmini, Luca Rosati EuroIA 2006, Berlin

Slide 2: The Evolution of Collaborative Tagging

Slide 3: An Emerging Approach to Distributed Classification Collaborative tagging systems are  used to organize, browse and share personal collections of resources through the introduction of simple metadata Folksonomies are user-generated  classifications, emerging through bottom-up consensus The basic idea is simply to make people  share items annotated with keywords FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 4: Collaborative Tagging Examples An incomplete list of online tagging systems may include simply, Connotea, magnolia, Taggly, digg, flickr, YouTube, Technorati, 43things. These are in fact web-based collaborative systems for: building a shared database of items  a flat metadata vocabulary  metadata driven queries  monitoring change in areas of interest  discovering emergences or trends  FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 5: Properties of Folksonomies Advantages Trade-off between simplicity and precision  Match the user’s real needs and language  Inclusive (nothing is left out)  Help discovery of information and serendipity  May be a forced move (the environment makes the difference)  Better than nothing (when traditional classification is not viable)  Disadvantages Language issues  User Experience issues  FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 6: Language Issues As a result of intrinsic language variability, tagging systems are also implicitly plagued by: Polysemy (window: is that a hole or a glass pane)  Homonymy (apple, jaguar)  Plurals (blog / blogs, folksonomy / folksonomies)  Synonymy (tags, tagging, folksonomy)  Ego-oriented tags (toread, funny, interesting etc..)  Basic level variations (dog / beagle)  These problems can dramatically reduce the effectiveness of the application and the benefits brought on by tagging systems FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 7: User Experience Issues Tag clouds are visual interfaces for information retrieval that provide a global contextual view of tags assigned to resources in the system Flat tag clouds are not sufficient to provide a semantic and multidimensional browsing experience. They have low findability quotient and low scalability  have high semantic density where few well-known  topics dominate the scene often follow an alphabetical criterion which limits the  ability to explore the tag cloud cannot visually support semantic relationships  often miss to provide complex logical operations  FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 8: Navigating Large Domains Information seekers in large domains of objects express the desire of having to  deal with meaningful groupings of related items, in order to quickly understand relationships and decide how to proceed [Hearst 2006]. How to generate and navigate such groups from a flat set of objects is anyway  a totally different matter. Taxonomies, clustering and faceted classification have been proposed in  the past as useful techniques for such purposes FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 9: Taxonomies Taxonomies are coherent and complete systems of meaningful labels which systematically organize a domain Taxonomies are organically crafted before starting to catalogue by professionals who deduce future user needs and content types They are authoritative centralized views and allow for greatear precision, avoiding ambiguity: the hierarchy provides context Major drawbacks do not have the ability to match the vocabulary  and the ways of thinking of different users expensive to build and maintain by professional  indexers FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 10: Clusters Clustering is the act of grouping  items according to some measure of similarity It reduces the semantic density and  improve the visual consistency of tag clouds But it generate messy groups,  conflates many different dimensions and does not allow refinement and follow-up queries Users prefer clear hierarchies  with categories at uniform levels of granularity over the unpredictable and unlabeled groupings typical of clustering techniques FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 11: Facets Facet name Facets are orthogonal descriptors  (categories) within a metadata system Each facet has a name and  addresses a different conceptual dimension or feature type relevant to the collection Each object is classified  combining labels from different facets Facets can be Flat or hierarchical  Assigned single or multiple  23 resources values FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 12: Facets Hierarchical faceted metadata can be used to add structure and context to tags  navigate along several dimensions  simultaneously seamlessly integrate browsing and  searching refine and broaden filtering criteria  FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 13: Benefits of Facets Easier to understand the meaning of tags  Large tag clouds more browsable  Reduction of the mental work (favouring recognition over recall)  Better support for exploration, discovery and iterative query refinement  Usability studies show how this approach is preferred over single hierarchies and clusters FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 14: What do we need then? A middle ground between the pure  democracy of bottom-up tagging and the empirical determinism of top- down controlled vocabularies A new metadata ecology which  merges and leverages emerging and traditional tools to improve findability and user experience This new metadata ecology has to be  a fusion, not only a simple process of coexistence FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 15: What FaceTag contributes What FaceTag tries to limit the impact of polysemy, homonymy and basic level  variation introducing a multidimensional and semantically richer paradigm FaceTag aims to improve the usability, findability, browsability,  serendipity and scalability of the system How FaceTag mixes three contributions to social tagging systems:  tag hierarchies  facets of tags  tagging and searching operate seamlessly  Users provide the faceted hierarchical structure through an intuitive user  experience FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 16: Faceted Analysis

Slide 17: How to choose facets Freehand Standard based each facet is decided on the each facet is found out   spot using Ranganathan's or CRG's guidelines the subject is freely  the subject is then deconstructed in several  deconstructed following a aspects general scheme each facet is find out at the  the general scheme works moment  as a prototype of every the subject is freely  particular faceted scheme deconstructed in several aspects FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 18: Benefits of standard compliance The standard-based approach brings along a number of benefits: it's a standard  experience demonstrates it suits several context  reduction of risks coming from a subjective perspective  FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 19: How we chose facets from the CRG general scheme CRG standard categories FaceTag facets Thing [Documents, resources] Type Resources Type (e.g. case study, report...) Part -- Property Language Material [Format] Process -- Operation Activities (e.g. competitive analysis, classification) Product [Deliverables] Byproduct -- Patient Target (e.g. Industry, Health...) Agent People, companies Space [Country] Time Document Date FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 20: FaceTag facets FaceTag facets Examples Resources Types case study  blog>enterprise web  Language predefined values (based on ISO  Standard ISO 639-2) Activities/Subjects discovery>competitive analysis  classification>facets  navigation design>breadcrumbs  Usage industry  public administration  software>companies>google  People dion hinchcliffe  morville  Date document date  FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 21: Benefits The blend of facets and tags bring benefits Vertical or paradigmatic axis on two axes Vertical when a user associates a keyword to a  facet the system suggests similar tags pertaining to the same facet. Horizontal the system allows the user to see all the  other tags belonging to the same facet. Horizontal or syntagmatic axis FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 22: Open Issues

Slide 23: What's “faceted” Metadata Facets Author Topic Title Activity Year Geo. Area Other Other Formal properties Semantic properties FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 24: Open issues Faceted Classification is a librarian theory postulating not only a multidimensional approach to an item  but also a semantic value of each dimension / facet  a specific citation order of such dimensions / facets  In some cases our ‘facets’ are not proper facets, but metadata nevertheless we need such metadata  so we may decide for a hybrid approach (facets & metadata)  Labeling of facets / metadata is yet another issue we have to better evaluate  FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 25: Technology Preview: FaceTag

Slide 26: Main page Resources with pertaining tags Search box with hinting Facets and pertaining tags FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 27: Using facets for searching: engaging 1 tag The user chooses 'intranet design' and facets and tags adjust. Breadcrumbing for the engaged tag appears (top). FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 28: Using facets for searching: intersecting 2 tags The user adds 'article' from another facet.Facets and tags adjust again. Breadcrumbing reflects the changes. Tags can be disengaged individually FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org

Slide 29: Using facets for searching: final result set The user adds 'shiv singh' from yet another facet and finds a final result set. Facets and tags adjust and show that there is no further possibility to zoom in. Breadcrumbing lists all engaged tags ready to be disengaged. 3 2 1 FaceTag - E. Quintarelli, A. Resmini, L. Rosati - www.facetag.org