OCLC Online Computer Library Center

Use of Circulation Statistics and Interlibrary Loan Data in Collection Management

Lynn Silipigni Connaway, Ph.D.

Office of Research, Consulting Research Scientist

Heather Wicht

Electronic Resources Librarian

University of Colorado at Boulder Libraries

Jennifer Knievel

Humanities Reference and Instruction Librarian

University of Colorado at Boulder Libraries

Study RationaleStudy Rationale

Statistics for decision making– Remote storage – Reduction of materials budget– Collection management

• Selection– Refinement of approval plan profiles

• Deselection

– WorldCat data mining• Gap/overlap holdings analysis• Unique/last copy• Audience level

CU Boulder Libraries CU Boulder Libraries

University of Colorado (CU) at Boulder – Research 1– Doctoral granting– 23,000 FTE

CU Libraries’ systems– Innovative Interfaces Integrated Library System– CLIO ILL Database

MethodologyMethodologyIdentification of a book– Monograph– Language material– No 007, except a, b, or d– No 245 $h– No 008, except d or r– Must have 260 $b or 020– 300 $a must include >49 pages

MethodologyMethodologyScope– Books owned by CU Libraries, except Law Library– 1/1/98-12/31/02– Text, including microform for ILL borrowing only– Exclusions

• Foreign language• Government documents• Dissertations and theses• Manuscripts• Music

MethodologyMethodology

Data sources CU – ILL borrowing data from CLIO

• Eliminated canceled requests

– Circulation data from Innovative Circulation Module

• Books circulated 1 or more times• Number of circulations versus number of items

circulated

– Holdings data from OCLC WorldCat

LimitationsLimitations

WorldCat holdings data – Include non-circulating books– Not complete holdings for CU library

Circulation, ILL, and holdings data– Eliminated books with no LCC for NATC

subject analysis = 112,499 titles

ResultsResults

1,146,655 books (holdings)

343,869 items circulated

25,038 ILL borrowing requests for books

North American Title Count (NATC)• Conspectus Divisions

ResultsResults

Use factor– Circulation within subject/holdings within

subject

Ratio of borrowings to holdings– ILL within subject/holdings within subject

ResultsResultsUse Factor– Low

• Library science, generalities, and reference 4,498/51,985=.09

• Physical education and recreation2,505/25,996=.10

• Anthropology3,935/29,126=.14

– High• Engineering and technology

21,799/17,155=1.27

• Physical sciences10,127/7,097=1.43

• Computer science5,480/2,048=2.68

ResultsResultsRatio of borrowing to holdings– Low

• Anthropology103/29,126=.004

• Library science, generalities, and reference280/51,985=.005

• Political science439/67,719=.006

– High• Agriculture

644/13,812=.047

• Music597/12,239=.049

• Engineering and technology1,939/17,155=.113

Future ResearchFuture Research

Circulation, ILL, and holdings data– Publication date– Publisher– Publication date within NATC subjects

ILL data– Status and department correlated to NATC

subjects

Number of items circulated

OCLC Online Computer Library Center

Questions and Discussion

connawal@oclc.orgHeather.Wicht@colorado.edu