OCLC Online Computer Library Center © 2004 OCLC Online Computer Library Center, Inc. Using Literary Warrant to Define a Version of the DDC for Automated Classification Services Diane Vizine-Goetz Research Scientist, OCLC Research Julianne Beall Assistant Editor, DDC ISKO Conference London, July 2004

2 Exploratory Study Defining a version of the DDC –To facilitate automatic assignment of DDC numbers to electronic documents –Based on literary warrant for topics in electronic resources

3 DDC for Automated Classification Machine classification service –A database of concepts used to classify a document –Software that generates a prioritized list of concepts that characterize the content of the document (Scorpion)

4 Checking Literary Warrant Primary source for checking literary warrant: BUBL –Ca. 12,000 Internet resources Canadian Information By Subject –Ca. 10,000 Internet resources KidsClick! –Ca. 6,400 Internet resources

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6 BUBL Site Statistics Dewey Class Number of sites Site Status ok US Sites UK Sites Total

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9 Defining a Version of the DDC Starting point: classification numbers in Abridged Edition 14 True abridgment: the truncated number for a topic is always the same as the full number for the topic, except shorter, e.g.: – Forecasting and forecasts of specific phenomena Cut back to Climatology and weather

10 Database Record Class number Caption Superordinate hierarchy Notes that describe what is found in a class Relative Index entries Mapped terminology

11 Keywords from Added to 551.6; Deleted Class-here note: methods of forecasting specific phenomena specific areas Relative Index entries, e.g., –Acid rainweather forecasting –Hurricanesweather forecasting –Rainweather forecasting Subject Headings for Children LCSH –StormsForecasting

12 Enriching Terminology for Numbers Built from Table 1 Example: built number Astronomy and allied sciences Relative Index terms that approximate the whole of 520: –Astronomy –Celestial bodies –Outer space –Spaceastronomy

13 Built Number Relative Index terms from T106, e.g.: –Associations –Organizations Combined entries for 520.6, e.g.: –Astronomyassociations –Astronomyorganisations –Astronomyorganizations –Celestial bodiesassociations –Celestial bodiesorganisations –Celestial bodiesorganizations

14 Subdivisions Added or Enriched

15 Added UK Spellings for Index Entries Number theory Factorisation number theory Factorizationnumber theory Number theory Prime numbers Mathematical optimization Mathematical optimisation Mathematical optimization Optimisationmathematical Optimization mathematics

16 A14.v1 base file + UK spelling A14.v2 base file + UK spelling + SS added/enriched A14.v3 base file + UK spelling + SS added/enriched + truncation Results: Scorpion & BUBL

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22 Next Steps Analyze where the truncation and the enriched terminology were useful and where not; revise the v3 database accordingly Extend approach to additional classes and projects (ePrints UK)

23 Links Research : Projects : ePrints-UK – mswitch/epuk.htmhttp:// mswitch/epuk.htm Dewey –