Collection Analysis with Circulation, ILL and Collection Statistics: A Follow-up Presentation Lynn Silipigni Connaway OCLC, Inc. Heather Wicht University of Colorado Jennifer Knievel University of Colorado

University of Colorado at Boulder (CU-Boulder)  Research I, Doctoral granting institution  26,500 FTE  Libraries hold ~3 million volumes (6/30/03)  87,000 ILL requests in ,000 Lending Requests 27,000 Borrowing Requests

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  Declining monographic budget Possible justification for maintaining or increasing monographic budget Accountability for spending

Purpose of Study  Compare subject distribution CU-Boulder holdings ILL borrowing requests Circulation

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

Project Scope  Books only  Law library excluded  Gov Docs excluded  Theses/dissertations excluded  Foreign language books excluded 20% of ILL requests  ILL borrowing transactions Cancelled (owned) requests excluded  Circulations Items circulating > 1 time

Numbers  970,784 books held in WorldCat  318,517 books circulated ,638,740 circulation transactions  22,064 ILL borrowing requests for books

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

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

Interpretation  Overall holdings Some subjects have very high publishing output Some subjects strongly dominated by journal literature or other non-book formats Scores

Greatest Number of Holdings by Subject Conspectus Subject CategoryHoldings Language, Linguistics, and Literature193,781 History and Auxiliary Sciences126,797 Business and Economics85,973 Engineering and Technology58,377 Philosophy and Religion50,024

Least Number of Holdings by Subject Conspectus Subject CategoryHoldings Law11,721 Chemistry9,504 Anthropology7,688 Physical Education and Recreation7,067 Agriculture6,490

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

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?

Greatest Number of Transactions per Item by Subject Conspectus Subject CategoryCirc Trans- actions Circ Items Trans- actions per Item Music53,8557, Computer Science35,3785, Sociology106,724 17, Physical Education and Recreation14,4322, Art and Architecture106,18617,9625.9

Least Number of Transactions per Item by Subject Conspectus Subject CategoryCirc Trans- actions Circ Items Trans- actions per Item Business and Economics102,58723, Political Science52,10811, Law15,9293, Education37,4258, Library Science, Generalities, and Reference15,5954,9723.1

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

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

Highest Percentage of Items Circulated by Subject Conspectus Subject CategoriesHoldingsCirc Items % Items Circulated Anthropology7,6883, % Sociology43,43717, % Computer Science12,9585, % Psychology13,4065, % Music18,4767, % Performing Arts 11,9214, %

Lowest Percentage of Items Circulated by Subject Conspectus Subject CategoryHoldingsCirc Items% Items Circulated Language, Linguistics, and Literature193,78156, % Chemistry9,5042, % Business and Economics85,97323, % Education33,3148, % Library Science, Generalities, and Reference33,3274, %

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

Interpretation  Ratio of holdings to ILL requests High ratio: 9:1 Many requests in subject area Evaluate whether local collection serving user needs Low ratio: 144:1 Very few requests in subject area Various interpretations

Highest ILL Ratio by Subject Conspectus Subject CategoryHoldingsILL ItemsHoldings : ILL Ratio Agriculture6, : 1 Medicine36,5012, : 1 Physical Education and Recreation7, : 1 Engineering and Technology58,3772, : 1 Sociology43,4371, : 1

Lowest ILL Ratio by Subject Conspectus Subject CategoryHoldingsILL ItemsHoldings : ILL Ratio Physical Sciences28, : 1 Education33, : 1 Political Science35, : 1 Language, Linguistics, and Literature193,7812, : 1 Library Science, Generalities, and Reference33, : 1

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

Circulations by Date

Interlibrary Loans by Publication Date

Limitations of Study  Time consuming  Materials used in library excluded  Circulation and ILL data for limited time period  Discipline and status of borrowers not identified  Only English monographs analyzed

Transition From Research to Practice  CU-Boulder data collection methods revised Reconfigure ILS data to capture Circulations/item/year Circulations by subjects identified by bibliographers Revised ILL request forms to require discipline and status

Gathering Your Data  Define a book Include or exclude Government documents Dissertations Microprint Non-circulating items Foreign language Branch library collections Make sure definition of book matches for every data set  Identify a time period What data are available for all three data sets?

Gathering Your Data  Determine what you need Holdings: bibliographic records (not item records) Circulations: transaction tallies, including dates ILL borrowing: initiated requests

Analyzing Your Data  OCLC numbers for all items  Combine data sets into a database (e.g. Access)  Use LCCs to map to Conspectus and NATC

Questions? Lynn Silipigni Connaway Consulting Research Scientist, OCLC, Inc. Heather Wicht Electronic Resources Librarian, CU Boulder