Taxonomies and Faceted Navigation Getting the Best of Both Tom Reamy Chief Knowledge Architect KAPS Group Knowledge Architecture Professional Services http://www.kapsgroup.com

Agenda Introduction: Essentials of Facets and Taxonomies Implementing Facets and Taxonomies Combining Taxonomies and Facets Conclusion

KAPS Group: General Knowledge Architecture Professional Services Virtual Company: Network of consultants – 12-15 Partners – Convera, Inxight, FAST, etc. Consulting, Strategy, Knowledge architecture audit Taxonomies: Enterprise, Marketing, Insurance, etc. Services: Taxonomy development, consulting, customization Technology Consulting – Search, CMS, Portals, etc. Metadata standards and implementation Knowledge Management: Collaboration, Expertise, e-learning Applied Theory – Faceted taxonomies, complexity theory, natural categories

Faceted Navigation: The Next Revolution Faceted navigation will change enterprise search! Faceted navigation will change the way business works! Faceted navigation means the end of taxonomies! Faceted navigation means no more metadata! Faceted navigation will eventually replace search! Faceted navigation will remove rust, polish your silver, feed the hungry, clothe the poor, and bring world peace! To All the Above – NAH!

Essentials of Facets Facets are not categories Entities or concepts belong to a category Entities have facets Facets are metadata - properties or attributes Entities or concepts fit into one or more categories All entities have all facets – defined by set of values Facets are orthogonal – mutually exclusive – dimensions An event is not a person is not a document is not a place. Facets – variety – of units, of structure Numerical range (price), Location – big to small Alphabetical, Hierarchical - taxonomic

History of Facets S. R. Ranganathan – 1960’s (Taxonomies – Aristotle) Issue of Compound Subjects The Universe consists of PMEST Personality, Matter, Energy, Space, Time Classification Research Group- 1950’s, 1970’s Facet analysis as basis for all bibliographic classifications Based on Ranganathan, simplified Principles: Division – a facet must represent only one characteristic Mutual Exclusivity More flexible, less doctrinaire Classification Theory to Web Implementation An Idea waiting for a technology - Multiple Filters / dimensions

Essentials of Taxonomies Internal Organization A hierarchy does not a taxonomy make. Taxonomy, browse structure, file structure Thesaurus, catalog, controlled vocabulary Two basic meanings – Formal and Browse Formal Taxonomy – parent – child relationship Is-A-Kind-Of ---- Animal – Mammal – Zebra Partonomy – Is-A-Part-Of ---- US-California-Oakland Browse Classification – cluster of related concepts Food and Dining – Catering - Restaurants

Essentials of Taxonomies Taxonomies are multiple purpose Indexing, browsing, communication, applications Taxonomies deal with complex, not compound Conceptual relationships – category membership Contextual relationships – Computers & Software Taxonomies deal with semantics Facets are mostly about things and their properties Taxonomies applied to documents Multiple meanings and purposes Essential attributes of documents are not single value

Taxonomies and Facets – Summary Is This a Facet? Important! A facet is not the same as top level categories in a taxonomy. Simple View: Taxonomies = complex concepts that are applied to documents Facets = one dimension of things More Complicated Documents are things – can have facet attributes – example – ContentType (format to purpose) Facets can have hierarchical structure Hybrid facets can have a taxonomic structure

Implementing Facets and Taxonomies Essentials of Faceted Navigation Not a Yahoo-style Browse Computer Stores under Computers and Internet One value per facet per entity Faceted Navigation Facets are filters, multidimensional Browse within a facet, filter by multiple facets Facets are applied at search time – post-coordination, not pre-coordination [Advanced Search] Faceted Navigation is an active interface – dynamic combination of search and browse

A Sideways Look at Faceted Navigation Miles wants a Pinot Noir And he doesn’t want any ____________ Merlot!

Implementing Facets and Taxonomies Faceted Navigation: Advantages More intuitive – easy to guess what is behind each door Simplicity of internal organization 20 questions – we know and use Dynamic selection of categories Allow multiple perspectives Ability to Handle Compound Subjects Trick Users into “using” Advanced Search wine where color = red, price = x-y, etc. Click on color red, click on price x-y, etc.

Implementing Facets and Taxonomies Faceted Navigation: Advantages Systematic Advantages: Need fewer Elements 4 facets of 10 nodes = 10,000 node taxonomy Content Management Advantages: Easier to “categorize” – not as conceptual Fewer = simple, can use auto-classification better Flexible – can add new facets, elements in facet

Implementing Facets and Taxonomies Faceted Navigation: Disadvantages Lack of Standards for Faceted Classifications Every project is unique customization Difficulty of expressing complex relationships Simplicity of internal organization Loss of Browse Context Difficult to grasp scope and relationships Essential Limit of Faceted Navigation Limited Domain Applicability – type and size Entities not concepts, documents, web sites Trade off between simplicity (power and ease of understanding) and complexity (real world)

Implementing Facets and Taxonomies When to Use Faceted Navigation Type of Collections Small to medium sized sets of things Homogenous set of entities Arbitrary Categorization of Domain Taxonomy of Office Supplies – yes Taxonomy of Life, Life Insurance – no. Nature of the domain and tasks Multi-dimensional area – no single hierarchy Nature of Important distinctions Can Create a Complete Set of Facets 3 or more mutually exclusive dimensions

Implementing Facets and Taxonomies Taxonomy: Advantages Rich Context Related concepts – Generalization and specification Browse – variety of types of relationships Standard taxonomies available Build on work of others Communication with others Multi-purpose Search – indexing, keywords Semantic signature of document Browse – conceptual context Applications - Alerts based on meaning in a document

Implementing Facets and Taxonomies Taxonomy: Advantages Knowledge Representation Higher level relationships User focus – their concept levels, nomenclature Faceted Taxonomies Advantages – smaller, scalability, conceptual clarity More complex, conceptual entities and relationships When to use: Size of element set Complexity of domain – concepts, documents, web pages

Implementing Facets and Taxonomies Taxonomy: Disadvantages Large, difficult to develop Pre-coordinated - can’t anticipate all of user’s needs Formal taxonomies do not represent user’s perspective Taxonomies are more difficult to use – often not clear where to go More difficult to use with auto-categorization Expensive

Implementing Facets and Taxonomies When to Use Taxonomies Complex Relationships If target is understand a rich set of related resources – yes If target is to buy an object - no Semantic If meaning in documents is primary – yes If targets are things or data documents - no Primary content is rich collection of documents Documents not about two or three things – multiple concepts, aboutness and minor topics Full text index mapped to taxonomy – support multiple perspectives into content, different purposes

Combining Facets and Taxonomies Development Issues – Facets Reflect current usage – expert community and user community Flexibility – allows for additions of new subject, facets, entities at any point in the system Match the structure to domain and task Users can understand different structures General: chronological, alphabetical, spatial, simple to complex, size or quantity, hierarchical, canonical Precision of unit values – very important!

Combining Facets and Taxonomies Development Issues – Facets Facetization of Taxonomy Same structure in multiple places in a taxonomy Hidden elements – get at with user focus Content type – Presentation, Well Report Level of Structure related to size of domain Alphabetical – list, range Number of Facets vs. Internal structure People – list or sub-structure – organizations, functions, etc. Labeling Systematic coherence vs. user labels, tasks

Combining Facets and Taxonomies Design Issues Bad Single set of facets, select and browse It’s just another category “Faceted” Search It’s just advanced search Better Combination of single facet browse and search Good Multiple facet browse and search Balance – purity of facets (easy to understand) with reflecting user’s world view and tasks

Combining Facets and Taxonomies Design Issues Dominant Dimension Semantic focus Single Facet – Hotel = location Equal facets or Main and Secondary facets Number of facets, user population Mixed paths or dedicated facet interface Wine.com – specials, time sensitive facets Facets within taxonomy – browse by wine type, then apply price, region facets

Facets and Taxonomies – Sample Implementations Rich Information Access Combining Subject Matter and Topical Facets Organization, Assets, Activities + Topics Browse Topics and filter by Assets & Activities Quality control for drilling new well in region X Geography facet and terrorism taxonomy Bomb making in Sudan Adding Attributes – Global and Local Content Types – presentations, well reports, policy Price – only shows up if intersection contains items with price metadata

Facets and Taxonomies – Sample Implementations Complex Work Space Combine faceted taxonomies, attribute facets, file structure People, Things, Events + Content Type File structure – where local group stores sets of related documents Links to wider universe Targeted links – by category, facet dimensions Find related people or policy documents Advantage of global context and local fast access

Facets and Taxonomies – Sample Implementations Ontologies and Alerts Ontology is a model of the relationships of a particular domain. Vice President – Related to Other people, HR policies, business activities Security rights, other implied behaviors Alerts – Software – entity extraction, facet extraction Old – if terms x,y,z appear Better – complex search – Near, Not, InSentence Better – Contains any of type x entity or facet (products), plus complex conceptual content, plus certain values within a facet (buying activity), then send alert

Faceted Taxonomy – Example KAPS Group Enterprise Taxonomy Basic Six Dimensions People individuals and communities Event Location Time Entities/ Things Information Resource – types Custom Facets / Taxonomies Products / Services Applications / Technologies Combine with subject matter taxonomies (MESH, etc.) Ontologies General Business relationships Industry specific Biotech Research Pipelines

Conclusion Taxonomies and facets are both part of intellectual infrastructure – supports multiple approaches, applications Dynamic classification is better than pre-coordinated structures Combine formal power with ability to support multiple user perspectives Formal taxonomies are best for dynamic classification Find the right blend of pure facets, hybrid facets, taxonomies, faceted taxonomies, ontologies, etc. Design for your situation – eCommerce or Enterprise Compound and Complex work, Complicated doesn’t

Questions? Tom Reamy tomr@kapsgroup.com KAPS Group Knowledge Architecture Professional Services http://www.kapsgroup.com