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 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 University of Colorado (CU) at Boulder –Research 1 –Doctoral granting –23,000 FTE CU Libraries systems –Innovative Interfaces Integrated Library System –CLIO ILL Database

Methodology Identification 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

Methodology Scope –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

Methodology 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

Limitations 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

Results 1,146,655 books (holdings) 343,869 items circulated 25,038 ILL borrowing requests for books North American Title Count (NATC) Conspectus Divisions

Results Use factor –Circulation within subject/holdings within subject Ratio of borrowings to holdings –ILL within subject/holdings within subject

Results Use Factor –Low Library science, generalities, and reference 4,498/51,985=.09 Physical education and recreation 2,505/25,996=.10 Anthropology 3,935/29,126=.14 –High Engineering and technology 21,799/17,155=1.27 Physical sciences 10,127/7,097=1.43 Computer science 5,480/2,048=2.68

Results Ratio of borrowing to holdings –Low Anthropology 103/29,126=.004 Library science, generalities, and reference 280/51,985=.005 Political science 439/67,719=.006 –High Agriculture 644/13,812=.047 Music 597/12,239=.049 Engineering and technology 1,939/17,155=.113

Future 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 Questions and Discussion