Collection Analysis with Circulation Data: What Usage Can Tell Us about Weeding and Collection Development

1. Collection Analysis with Circulation Data: What Usage Can Tell Us about Weeding and Collection Development Jennifer E. Knievel and Heather Wicht University of Colorado Lynn Silipigni Connaway OCLC, Inc.

2. Univ. of Colorado at Boulder Research I, Doctoral granting institution 26,500 FTE Libraries hold ~3 million volumes (6/30/03) 87,000 ILL requests in 2003 60,000 Lending Requests 27,000 Borrowing Requests

3. Project Origins Remote storage project at CU-Boulder Collaboration with OCLC – mining WorldCat Collection development study by John N. Ochola, Baylor University Planning of pilot project Identify data to be analyzed, collected in future Assess usefulness of data to bibliographers

4. Purpose of Study Compare subject distribution of UCB holdings ILL borrowing requests Circulation

5. Local Systems Software Innovative Interfaces CLIO Database Data Gathering Methods Innovative: Create Lists CLIO: Microsoft Access Queries

6. Project Scope Books only Law library excluded Gov Docs excluded Theses/dissertations excluded Foreign language books excluded 20% of ILL requests ILL borrowing transactions 1998-2002 Cancelled (owned) requests excluded Circulations 1995-2003/1998-2002 Non-circulating items excluded

7. Data Collected ILL Request Origin, OCLC #,Title, Author, Edition, Publisher, Pub Date, ISBN, Patron Status & Dept, Request Status Circulation OCLC #, Title, Author, Publisher, Pub Date, ISBN, LCC, Total # Checkouts Holdings OCLC#, Title, Author, Publisher, Pub Date, ISBN, LCC

8. Numbers 970,784 books held in WorldCat 318,517 books circulated 1998-2002 1,638,740 circulations on those books 1995-2003 22,064 borrowing requests for books 1998-2002

9. Data Manipulation ILL requests lacked LCC numbers Mapped to WorldCat records by OCLC # All data sets mapped by LCC: 600+ North American Title Count (NATC) subject categories 24 Research Libraries Group (RLG) Conspectus Divisions

10. Results Overall holdings Total holdings No multiple copies counted, just titles Derived from OCLC WorldCat, but could be pulled locally

11. Interpretation Overall holdings Some subjects have very high publishing output Some are strongly dominated by journal literature or other non-book formats (e.g. scores)

12. Results Average transactions per item Transactions in a subject Items circulated in a subject Transactions/items = average transactions per item Example: 10,000 transactions, 5,000 items, average 2 transactions per item

13. Interpretation Average transactions per item High average: 7.4 circs per item Extremely active subject area Where is activity occurring? Low average: 3.1 circs per item Low check out rate Is collection relevant? What kind of usage?

14. Results Percentage of items circulated Total items in a subject Items circulated in a subject Circulated /items in subject = percentage circulated Example: 8,000 items in subject, 2,000 items circulated = 25% items circulated

15. Interpretation Percentage of items circulated High percentage: 43.3% Almost half of books circulated during study Circulation is widely distributed across subject Low percentage: 14.9% Less than one quarter of books circulated Circulation is very narrow, or use is mostly in-house

16. Results Ratio of holdings to ILL requests Comparing apples to oranges, but still useful Total items in subject ILL requests in subject Items in subject : ILL requests = ratio Example: 12,000 items in subject, 1,000 requests = 12:1

17. Interpretation Ratio of holdings to ILL requests High ratio: 9:1 Many requests in that subject area Evaluate whether local collection is serving user needs Low ratio: 144:1 Very few requests in that subject area Various interpretations Could indicate needs met, low collection interest, dominance of undergraduates not using ILL, enormous held collectionCould indicate needs met, low collection interest, dominance of undergraduates not using ILL, enormous held collection

18. Example: Sociology Medium number of holdings: 43,437 High transactions per item: 6.0 High percentage items circulated: 41.0% High ratio holdings : ILL requests: 26.0:1 Interpretation Extremely active subject area, both high circs and high requests. Requests do not indicate that collection is not targeted. High activity could be due to interdisciplinary nature of subject.Extremely active subject area, both high circs and high requests. Requests do not indicate that collection is not targeted. High activity could be due to interdisciplinary nature of subject.

19. Getting Your Data Define a book Include or exclude gov docs, dissertations, microprint, non-circulating items, foreign language, branch libraries Make sure definition of book matches for every data set Identify a time period What data is available for all three data sets?

20. Getting Your Data Figure out what you need Holdings: bib records (not item records) Circulations: transaction tallies, including dates if possible ILL borrowing: initiated requests

21. Comparing Your Data OCLC numbers for all items Combine data sets into a database (e.g. Access) Use LCCs to classify into Conspectus and NATC Mention 65,000 limit in Excel.Mention 65,000 limit in Excel.

22. Questions? Jennifer E. Knievel Humanities Reference Librarian, CU Boulder 303-492-8887 jennifer.knievel@colorado.edu