Taxonomies and Faceted Navigation

Getting the Best of Both

Tom ReamyChief Knowledge Architect

KAPS Group

Knowledge Architecture Professional Services

http://www.kapsgroup.com

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Agenda

Introduction: Essentials of Facets and Taxonomies

Implementing Facets and Taxonomies

Combining Taxonomies and Facets

Conclusion

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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

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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!

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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

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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

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Essentials of TaxonomiesInternal 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

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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

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Taxonomies and Facets – SummaryIs 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

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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

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A Sideways Look at Faceted NavigationMiles wants a Pinot NoirAnd he doesn’t want any ____________ Merlot!

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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.

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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

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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)

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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

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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

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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

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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

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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

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Combining Facets and TaxonomiesDevelopment 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!

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Combining Facets and TaxonomiesDevelopment 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

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Combining Facets and TaxonomiesDesign 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

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Combining Facets and TaxonomiesDesign 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

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Facets and Taxonomies – Sample ImplementationsRich 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

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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

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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

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Faceted Taxonomy – ExampleKAPS 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

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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 Reamytomr@kapsgroup.com

KAPS Group

Knowledge Architecture Professional Services

http://www.kapsgroup.com