Module 8a: Faceted Classification

1. Module 8a: Faceted Classification IMT530: Organization of Information Resources Winter 2008 Michael Crandall

2. Overview • Enumerated vs. analytico-synthetic techniques • History of faceted classification – Ranganathan & CRG • Facets • Examples • Facet analysis • Spiteri’s simplified model • Process • Use of facets in information systems IMT530 Organization of Information Resources

3. Enumerated Classification vs. Faceted Classification • Enumerated classification • One-dimensional • Dewey Decimal Classification System • Library of Congress Classification System • Rigid hierarchical approach • Gives a single schedule that enumerates fully the classes and their ready-made class numbers IMT530 Organization of Information Resources

4. Enumerated Classification vs. Faceted Classification • Analytico-Synthetic (Faceted Classification) • Multi-dimensional • Clearly defined, mutually exclusive, and collectively exhaustive aspects, properties, or characteristics of a class or specific subject IMT530 Organization of Information Resources

5. Faceted Classification • FA (Facet Analysis) - (analytical technique) • Listing of characteristics of the entities in a universe (exhaustive, mutually exclusive) • FC (Facet Classification) - (synthetic structure) • Structure – division of entities in a universe (by one characteristic at a time) • Synthesis – combination of relevant facets: • Schedule of terms for description • Assignment of notation IMT530 Organization of Information Resources

6. Origin of Faceted Classification • A Hindu mathematician • Worked as a librarian • Started from the limits of traditional enumerative classification systems • Attempted to describe the entire universe of ideas • 1930s • Colon Classification – Analytico-synthetic classification system (1933) Ranganathan (1892 - 1972) IMT530 Organization of Information Resources

7. Analyze each document Group isolates (simple-concept subjects) into the facets Order the isolates within the facets Establish a citation order for facets (Ranganathan’s is P-M-E-S-T) Establish a schedule order for the facets Apply the notational system Compile schedules & generate an index Basic Ranganathan IMT530 Organization of Information Resources

8. Ranganathan’s 5 Facets • Personality : Who • Matter: What • Energy: How • Space: Where • Time: When IMT530 Organization of Information Resources

9. Ranganathan’s Rule • 46 Canons : Must follow • 13 Postulates : Strongly recommended • 22 Principles : Strongly recommended IMT530 Organization of Information Resources

10. Examples • Ranganathan's Colon Classification • research in the cure of tuberculosis of lungs by x-ray conducted in India in 1950 • L,45;421:6;253:f.44'N5 • Medicine,Lungs;Tuberculosis:Treatment;X-ray:Research.India'1950 IMT530 Organization of Information Resources

11. Classification Research Group (CRG) • UK (1952) • Produced classification systems for narrower, specialized areas • Designed several subject-specific faceted classification systems IMT530 Organization of Information Resources

12. Ranganathan & the CRG • Agree about the essential qualities of a facet • Mutually exclusive; each facet represents a characteristic not found in any other facet • Relationships between facets are non-hierarchical IMT530 Organization of Information Resources

13. Facets • The broad categories into which the subject area is divided. A facet consists “... of a group of terms that represents one, and only one, characteristic of division of a subject field....no two facets may contain terms that could represent the same concepts.” Spiteri, L. (1998) A Simplified Model for Facet Analysis. Canadian Journal of Information and Library Science v23, 1-30 (April-July 1998). http://iainstitute.org/pg/a_simplified_model_for_facet_analysis.php • “Clearly defined, mutually exclusive, and collectively exhaustiveaspects, properties or characteristics of a class or specific subject"Maple, A. (1995) Faceted Access: A Review of the Literature http://www.musiclibraryassoc.org/BCC/BCC-Historical/BCC95/95WGFAM2.html IMT530 Organization of Information Resources

14. Examples of Facets • Petersen (1994) – the Art & Architecture Thesaurus • Associated Concepts/ Physical Attributes/ Styles and Periods/ Agents / Activities/ Materials/ Objects • Business • Products/ Applications/ Organizations/ People/ Domain objects/ Events/ Publications IMT530 Organization of Information Resources

15. Epicurious.com • Recipe collection on the web • Cuisine • Special considerations • Meal/Course • Dish • Main Ingredients • Preparation methods • Season/Occasion IMT530 Organization of Information Resources

16. Examples • Faceted Classification • Epicurious http://www.epicurious.com/recipes/find/advanced/ • Wine.com http://www.wine.com/wineshop/ • Flamenco http://flamenco.berkeley.edu/demos.html • Images of England http://www.imagesofengland.org.uk • lawforwa.org http://www.lawforwa.org/search/advsearch.html • FAT-HUM Project http://www.ucl.ac.uk/fatks/php/browse.php • Tools • FacetMap’s Wine demonstration http://facetmap.com/download/starterKit.jsp • Siderean software http://www.siderean.com/ • Endeca software http://endeca.com/ IMT530 Organization of Information Resources

17. Characteristics of a Faceted Classification System • Based on the important, essential or persistent characteristics of content objects • More than hierarchies • Easy to extend by adding a new facet • Flexibility • Easier to construct • Easy to formulate composite subjects • Easy to accommodate new concepts • Provides multiple access points to content IMT530 Organization of Information Resources

18. Facet Analysis • “Facet analysis is a mental process involving analysis of a subject into its facets based on a set of postulates, canons and principles. It provides a framework to accommodate various types of terms, along with rules for their combination.”—K. Kumar • Facet analysis is the sorting of terms in a given field of knowledge into “homogenous, mutually exclusive facets, each derived from the parent universe by a single characteristic of division ... every distinctive logical category should be isolated, every new characteristic of division should be clearly indicated.”—B. C. Vickery IMT530 Organization of Information Resources

19. Planes of Work • The Idea Plane – the process of analyzing a subject field into its component parts • The Verbal Plane – the process of choosing appropriate terminology • The Notational Plane – the process of expressing these component parts by means of a notational device IMT530 Organization of Information Resources

20. Idea Plane: Principles for the Choice of Facets • Differentiation • Divide by a clearly defined characteristic of division • E.g., Humans by Gender • Relevance • Reflect the purpose and scope of the classification system • E.g., Children by Grade, but not for Dogs • Ascertainability • Definite and ascertainable facts • E.g., Date of birth for Humans, Breed for Dogs • Permanence • Permanent qualities of the entity • E.g., Color wouldn’t work for chameleons IMT530 Organization of Information Resources

21. Idea Plane: Principles for the Choice of Facets • Homogeneity • Facets must not overlap • E.g., geography and product names • Mutual Exclusivity • Facets represent only one characteristic • Fundamental Categories • Categories should be derived from the domain • Disagrees with Ranganathan’s universal PMEST IMT530 Organization of Information Resources

22. Idea Plane: Principles for the Citation Order of Facets and Foci • Relevant Succession • Chronological Order • Alphabetical Order • Spatial/Geometric Order • Simple to Complex Order (or Complex to Simple) • Canonical Order • Increasing Quantity (or Decreasing Quantity) • Consistent Succession IMT530 Organization of Information Resources

23. Principles for the Verbal Plane • Context • Meaning is determined by position in the system Grain dishes Rice dishes White rice dishes With raisins Brown rice dishes • Currency • Should use terminology appropriate for the language in use at time of indexing IMT530 Organization of Information Resources

24. Guidelines for Faceted Classification • Study the domain • (Context) Examine the domain • (Content) Study information objects • (Users) Who? Information Needs? • Entity listing • Facet creation • Facet arrangement • Citation order • Classification • Revision, testing, and maintenance IMT530 Organization of Information Resources

25. Use of the Facet Approach • Traditional Use • Classification • Thesaurus • Indexing • Information Systems • Information Architecture & User-Centered Design • Navigation and browse • Information Retrieval • Individual facets can be accessed and retrieved either alone or in any desired combination IMT530 Organization of Information Resources

26. Faceted Approach in IS • Simple in structure • Flexible in application • Amenable to software applications • Amenable to computer assisted indexing and validation • Interoperable with the majority of modern indexing vocabularies • Easier and more economical to maintain than enumerated vocabularies IMT530 Organization of Information Resources

27. Faceted Navigation IMT530 Organization of Information Resources

28. Facet-based Advanced Search IMT530 Organization of Information Resources

29. Combined IMT530 Organization of Information Resources

30. Usability Testing of Faceted Approaches • Flamenco developed by Marty Hearst and others to test facets for images • Built an interface to support both direct search and browsing • Supports search usability guidelines • Nine facets • Opening – Middle Game – Endgame • http://bailando.sims.berkeley.edu/flamenco.html IMT530 Organization of Information Resources

31. Usability Studies – Flamenco (Hearst et al., 2003) • Usability Study for Search • 32 art history students • Search by Faceted Metadata vs Baseline • More Successful • More usage time • 90% - Preferred the metadata approach overall • 97% - Helped users learn more about the collection • 75% - More flexible • 72% - Easier to use IMT530 Organization of Information Resources

32. Problems of Faceted Approach • Mismatched labeling • Inconsistent category metadata • Difficulty in deciding on the correct or appropriate facet • Challenges in defining a useful and usable collection of facets IMT530 Organization of Information Resources

33. Recap • Enumerated classification (Hierarchical) • One-dimensional • Dewey Decimal Classification System • Library of Congress Classification System • Rigid Hierarchy • Gives a single schedule that enumerates fully the classes and their ready-made class numbers. • Analytico-Synthetic (Faceted Classification) • Multi-dimensional • Clearly defined, mutually exclusive and collectively exhaustive aspects, properties, or characteristics of a class or specific subject IMT530 Organization of Information Resources

34. Recap • Hierarchical and faceted approaches are not mutually exclusive • You can use hierarchies under facets to help with entry vocabulary and cross references • You may not always be able to apply mutual exclusion and exhaustivity to facets, but you should use these principles to help clarify • Spiteri’s Idea Plane is where you do this work • Try to apply terms from all facets to each object (webpage) you’re tagging to see what happens • If it doesn’t make sense, you probably need to rethink your facets IMT530 Organization of Information Resources

35. IMT530 Organization of Information Resources