INF 384 C, Spring 2009 Subject Languages Category structures to represent topics

INF 384 C, Spring 2009 Outline Why? What are the goals of subject languages? What? What do subject languages look like? How? On what basis are subject languages created?

INF 384 C, Spring 2009 Goals of subject languages Ranganathan: To provide a helpful sequence of documents, so that: Readers discover topics that may be useful. Books can display their potential to readers. Svenonius: To improve collocation in retrieval; to navigate the bibliographic universe; to represent knowledge (as opposed to information).

INF 384 C, Spring 2009 Components of subject languages Subject languages contain concepts represented as terms. The concept of “pH of water components of soil, and the effects of this pH on the soil’s use in supporting plant life,” may be represented as the term “soil acidity.”

INF 384 C, Spring 2009 Structure of subject languages Alphabetical representation and classified representation. Synthetic structure and enumerative structure. Parallel hierarchies and facets.

INF 384 C, Spring 2009 Examples of alphabetic representation Architecture Art Biology Chemistry Engineering Fine arts Life sciences Architecture BT Fine arts NT Landscape architecture Biology BT Life sciences NT Evolutionary biology, molecular biology

INF 384 C, Spring 2009 Example of classified representation Arts and sciences Fine arts Visual art Architecture Landscape architecture Music Sciences Life sciences Biology New York Times information architecture

INF 384 C, Spring 2009 Examples of synthetic structure In Ranganathan’s Colon Classification, subjects are constructed by arranging concepts from the facets Personality, Matter, Energy, Space, and Time (PMEST). In the Dewey Decimal Classification, geographic information is appended to a class name by means of standard tables. Topical example from Dewey blog: Bank deposit insurance—United States The number is built with plus 0 (extra 0 for standard subdivisions as instructed in the add table under 368.1–368.8 Specific kinds of insurance) plus T1—09 Geographic treatment plus T2—73 United States.

INF 384 C, Spring 2009 Example of enumerative structure Warburg Institute classification: Image hierarchy main classes Primitive Art, Oriental Art, Classical Archaeology, Classical Topography, Classical Iconography, Numismatics, Greek Art, Roman Art, History of Art, Sources of the History of Art, Art Interpretation, Aesthetics, Topography, Iconography, Survival Of Ancient Art, Early Christian & Byzantine Art, Illuminated Manuscripts, Italian Art, Spanish Art, French Art, Flemish & Dutch Art, British Art, German Art, Scandinavian Art, Applied Arts, Art Collecting, 19th & 20th Century Art

INF 384 C, Spring 2009 Examples of parallel hierarchies 04 POLITICS 0406 political framework 0411 political party 0416 electoral procedure and voting 0421 parliament 0426 parliamentary proceedings 0431 politics and public safety 0436 executive power and public service 08 INTERNATIONAL RELATIONS 0806 international affairs 0811 cooperation policy 0816 international balance 0821 defence 10 EUROPEAN COMMUNITIES 1006 Community institutions and European civil service 1011 European Union law 1016 European construction 1021 Community finance From the Eurovoc thesaurus, used to describe EU government documents:

INF 384 C, Spring 2009 Examples of facets In the Bliss Bibliographic Classification (BBC v.2), the Human Biology and Medicine field is organized into the following facets: Types of persons Parts and systems of the person Processes in the person Actions on the person Agents of actions A document whose subject is nursing for children with cancer would be described as: (Type of person) Paediatrics - (Processes) - Pathological - Cancer - (Actions on) Nursing Example from Bliss Classification Association:

INF 384 C, Spring 2009 Internal structure of subject languages Hierarchical relationships. Equivalence relationships. Associative relationships.

INF 384 C, Spring 2009 Scope of hierarchical relationships Universal hierarchies (mammal -> dog). Always true! Perspective hierarchies (pet -> dog, or work animal -> dog, or food -> dog). Only true under a certain point of view or certain conditions. Can a subject language ever attain universality?

INF 384 C, Spring 2009 Types of hierarchical relationships Genus-species Follow the all-some rule—X is a type of Y if all X’s are Y’s but only some Y’s are X’s: all dogs are mammals but not all mammals are dogs. All the sibling concepts should follow the same principle of division and be mutually exclusive, or multiple principles of division should be elucidated through the structure. Whole-part Often treated as associative relationships in subject languages. A few exceptions: Systems and organs of the body Geographical locations Disciplines and subdisciplines Hierarchical social structures Instance Not types but instances: they involve proper names (Seas: Baltic Sea, Mediterranean Sea). Not part of your subject language!

INF 384 C, Spring 2009 Examples of genus-species relationships Single principle of division Programming languages Declarative languages Functional languages Imperative languages Object-oriented languages Procedural languages Multiple principles of division People (by family role) mothers fathers children (by occupation) opera singers information professionals mushroom hunters

INF 384 C, Spring 2009 A negative example Unclear principles of division Paintings Portraits Renaissance paintings Oil paintings Cave paintings Impressionist paintings Landscapes Murals These concepts do indeed describe types of paintings, but they represent multiple perspectives on painting. Mixing principles of division like this makes the structure difficult to understand and browse. (If we did need to place an item in one location, it would be impossible, as well.)

INF 384 C, Spring 2009 Examples of subject languages Warburg Institute classification. Alcohol and Other Drugs thesaurus.

INF 384 C, Spring 2009 Defining the scope of subject languages What marks the extent of a subject? Should a classification of “information organization” as a subject include information retrieval? Should it include philosophy of language? Should it include critical theory? How does one make such decisions?

INF 384 C, Spring 2009 Rationale for including concepts in subject languages Literary warrant. Use warrant. Structural warrant. Cultural warrant. Others?

INF 384 C, Spring 2009 Example of structural warrant atmospheric railway cable haulage railway counterbalanced railway water balance railway rope haulage railway gravity railway animal powered railway horse railway locomotive railway electric railway From the MDA Railway Object Name thesaurus

INF 384 C, Spring 2009 Basic design process for subject languages Define the subject. How? Do research. Define the context. Think. Determine the concepts to include. How? Do research. Consider the context. Think. Structure the concepts with hierarchical and associative relationships. Add, delete, broaden, or narrow concepts to balance the structure. Arrange the concepts at each hierarchical branch.

INF 384 C, Spring 2009 Your current mission Research the subject. Determine a purpose and audience for your classification. Use the purpose and audience to define and scope the subject. Collect concepts for potential inclusion.