© 2004 OCLC Online Computer Library Center, Inc.

OCLC Online Computer Library CenterUsing Literary Warrant to

Define a Version of the DDC for Automated

Classification Services Diane Vizine-Goetz

Research Scientist, OCLC ResearchJulianne Beall

Assistant Editor, DDCISKO Conference

London, 13-16 July 2004

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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

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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)

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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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http://bubl.ac.uk/link/ddc.html

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BUBL Site Statistics

DeweyClass

Numberof sites

Site Status ok

USSites

UKSites

500 135 103 59 27

510 167 36 65 43

520 186 133 84 25

530 139 111 68 20

540 118 82 38 33

550 247 196 127 30

Total 992 761 441 178

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http://www.nlc-bnc.ca/caninfo/esub.htm

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http://sunsite.berkeley.edu/KidsClick!/dewey.html

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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.:– 551.64 Forecasting and forecasts of

specific phenomena •Cut back to 551.6 Climatology and

weather

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Database Record

Class number

Caption

Superordinate hierarchy

Notes that describe what is found in a class

Relative Index entries

Mapped terminology

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Keywords from 551.64 Added to 551.6; 551.64

DeletedClass-here note: methods of forecasting specific phenomena specific areas

Relative Index entries, e.g.,– Acid rain—weather forecasting– Hurricanes—weather forecasting– Rain—weather forecasting

Subject Headings for Children LCSH– Storms—Forecasting

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Enriching Terminology for Numbers Built from Table 1

Example: built number 520.6

520 Astronomy and allied sciences

Relative Index terms that approximate the whole of 520: – Astronomy– Celestial bodies– Outer space– Space—astronomy

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Built Number 520.6

Relative Index terms from T1—06, e.g.:– Associations– Organizations

Combined entries for 520.6, e.g.:– Astronomy—associations– Astronomy—organisations– Astronomy—organizations– Celestial bodies—associations– Celestial bodies—organisations– Celestial bodies—organizations

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505 Science Serial publications 1_05 506 Science Organizations 1_06 507.2 Science Research; statistical methods 1_072 507.4 Science Museums, collections, exhibits 1_074 509 Science Historical, geographic, persons treatment 1_09 509.2 Science Persons 1_092 510.28 Mathematics Auxiliary techniques and procedures; apparatus, equipment 1_0285 510.5 Mathematics Serial publications 1_05 510.6 Mathematics Organizations 1_06 510.71 Mathematics Education 1_071 510.9 Mathematics Historical, geographic, persons treatment 1_09 520.6 Astronomy Organizations 1_06 526.06 Cartography Organizations 1_06 530.05 Physics Serial publications 1_05 530.06 Physics Organizations 1_06 530.071 Physics Education 1_071 540.5 Chemistry Serial publications 1_05 540.6 Chemistry Organizations 1_06 540.71 Chemistry Education 1_071 550.5 Earth sciences Serial publications 1_05 550.6 Earth sciences Organizations 1_06 550.71 Earth sciences Education 1_071 551.4606 Hydrosphere and submarine geology Oceanography Organizations 1_06 551.4607 Hydrosphere and submarine geology Oceanography Education and research 1_071; 1_072

Subdivisions Added or Enriched

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Added UK Spellings for Index Entries

512.7

Number theory

Factorisation—number theory

Factorization—number theory

Number theory

Prime numbers

519.6

Mathematical optimization

Mathematical optimisation

Mathematical optimization

Optimisation—mathematical

Optimization—mathematics

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Match Type A14 base A14.v1 A14.v2 A14.v3 Exact 139 139 129 183 Partial 155 155 186 167 Exact or Partial 294 294 315 350 Non-match 455 455 434 399 Total 749 749 749 749

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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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)

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Links

Research : Projects : ePrints-UK– http://www.oclc.org/research/projects/

mswitch/epuk.htm

Dewey– http://www.oclc.org/dewey/