designing collection experiences: availability
DESCRIPTION
Availability as the primary measure of public library collection performance.TRANSCRIPT
Designing Collection Experiences:2. Availability
www.whatwouldranganathando.orgSeptember 17 & October 1, 2013
Waterloo Public Library
Measurement
Exercise
What are some collection performance measures?
Input
Output
Outcome
“The most important figures that one needs for management are unknown or unknowable… but successful management must nevertheless take account of them.”
W. Edwards Deming. Out of the Crisis. Cambridge, Mass.: Massachusetts Institute of Technology, Center for Advanced Engineering Study, 1986, p. 121, crediting Lloyd S. Nelson.
The mission of librarians is to help create transformative meaning in the lives of readers and the conversations of communities.
The Many Collections Hypothesis
Charlie Robinson Baltimore CountyPublic Library
“Give ‘em what they want, when they want it.”
Availability
Availability: Are the texts that the reader would prefer to select presented when the reader would prefer to select them?
Reader Library
Texts
CollectionIn
UseShelved
Collection
OtherText
Experiences
OtherLibrary
Experiences
Ratio
Rod Pierce. "Definition of Ratio." Math Is Fun. Ed. Rod Pierce. August 24, 2013. http://www.mathsisfun.com/definitions/ratio.html
1,500 items in use
8,500 items shelved
1. What is the ratio of items in use to items in the collection?
2. What is the ratio of items on the shelf to items in the collection?
10,000 items in the collection
Availability Surveys
Measuring reader satisfaction
Availability survey ratio:just ask the readers…
𝐴𝑣𝑎𝑖𝑙𝑎𝑏𝑖𝑙𝑖𝑡𝑦=𝐼𝑡𝑒𝑚𝑠 𝑓𝑜𝑢𝑛𝑑
𝐼𝑡𝑒𝑚𝑠 𝑙𝑜𝑜𝑘𝑒𝑑 𝑓𝑜𝑟
Van House, Nancy A., Mary Jo Lynch, Charles R. McClure, Douglas L. Zweizig, and Eleanor Jo Rodger. Output Measures for Public Libraries: A Manual of Standardized Procedures. 2nd ed. Chicago: American Library Association, 1987.
“The principle categories of dissatisfaction”Paul B. Kantor "Availability Analysis," Journal of the American Society for Information Science 27, no. 5 (September-October 1976) 311-19.
F=109FrustrationSuccess
Exercise
What are some sources of library and reader error in availability studies?
Library Error & Reader Error
Library Error Reader Error
Bill Price and David Jaffe. The Best Service Is No Service: How to Liberate Your Customers From Customer Service, Keep Them Happy, and Control Costs. San Francisco: Jossey-Bass, 2008.
Rhizomes
Unlike the graphic arts, drawing, or photography, unlike tracings, the rhizome pertains to a map that must be produced, constructed, a map that is always detachable, connectable, reversible, modifiable, and has multiple entranceways and exits and its own lines of flight. It is tracings that must be put on the map, not the opposite.
Gilles Deleuze and Félix Guattari. A Thousand Plateaus: Capitalism and Schizophrenia, translated and with a forward by Brian Massumi. Capitalism and Schizophrenia, 2. Minneapolis University of Minnesota Press, 1987, p. 20.
Rhizomes Mj
Holdings Mjavailability Mj
Shelf Mjavailability Mj
Holdings Mjavailability Mj
Relative Use Mj
Brief Tests Mj
Relative use
The relation between the holdings ratio and circulation ratio of a rhizome. An indicator that a rhizome may be over-sized or under-sized.
Relative use
F. Wilfred Lancaster,. If You Want to Evaluate Your Library . . . 2nd ed. Champaign, IL: University of Illinois, Graduate School of Library and Information Science, 1993.
Gregory R. Mostyn. "The Use of Supply-Demand Equality in Evaluating Collection Adequacy," California Librarian 35 (April 1974) 16-23.
Holdings ratio
Circulation ratio
Collection Holdings Ratio
Circulation Ratio Relative Use
Youth .25 .50 2.00
Adult .75 .50 .67
Relative use
Collection Holdings Circulation HoldingsRatio
Circulation Ratio Relative Use
Youth 8,000 19,500 0.24 0.35 1.4
Adult 20,000 21,000 0.61 0.37 0.6
Media 5,000 16,000 0.15 0.28 1.9
Total 33,000 56,500
Other applications of relative use
• Interlibrary loan• Holds• Missing or not returned• Withdrawn for damage or wear
Holdings Mjavailability Mj
Relative Use Mj
Brief Tests Mj
Brief Test Holdings Availability
White, Howard D. Brief Tests of Collection Strength: A Methodology for All Types of Libraries. Westport, CT Greenwood, 1995.
Brief Test Holdings Availability
Measures of MjCentral Mj
Tendency Mj
Mean Mj
Median Mj
Rod Pierce. "How to Calculate the Mean Value" Math Is Fun. Ed. Rod Pierce. April 21, 2013. http://www.mathsisfun.com/mean.html
Rod Pierce. "Definition of Median" Math Is Fun. Ed. Rod Pierce. Aug 23, 2013.
http://www.mathsisfun.com/definitions/median.html
Picture book holdings in Iowa libraries
The Language of the Levels
Conspectus0. Out of scope1. Minimal2. Basic information3. Instructional support4. Research5. Comprehensive
Not Conspectus• Happiness• Glee• Eternal joy• The cat’s pajamas
Takeaway from “Brief Tests” holdings measure
Validate checklists by looking in a union catalog (WorldCat, Iowa Locator, etc.) to find the distribution of holdings for each title. More holdings means a title that will appeal to more readers.
Shelf Mjavailability Mj
Random Mj
Reader- Mjweighted Mj
Random Availability
Random sample from shelf list
1,500 items in use
8,500 items shelved
Snapshot
Snapshot: A snapshot is a download of status data about the items in a collection at a specific instant in time. Because status data cycle slowly over loan periods, snapshots provide stable indicators of long-term relationships and trends.
Circulation Period Daily change1 week 0.14
2 weeks 0.073 weeks 0.054 weeks 0.04
Exercise
Explain why it is misleading to use a Random Availability snapshot of a collection as an indicator of the availability that the reader actually experiences.
Reader-Weighted Availability
Shelf Mjavailability Mj
Random Mj
Reader- Mjweighted Mj
Collection Adult 500s Adult 900s Board Books DVDs Beginning Readers
Adult Fiction0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0
0.930.95
0.65
0.47
0.89
0.94
0.00
0.94 0.95
0.40
0.27
0.57
0.82
RandomReader-Weighted
Comparison between random and reader-weighted availabilityData from Grimes Public Library, September 2004
Reader- Mjweighted Mj
Availability Mj
Sample from MjCollection in Use Mj
Estimate from MjDemand tables Mj
Reader-Weighted Availability: Sample from collection in use
Roger Edward Stelk and F. Wilfred Lancaster. "The Use of Shelflist Samples in Studies of Book Availability," Collection Management 13, no. 4 (1990) 19-24.
1,500 items in use
8,500 items shelved
Random Sample
Reader-Weighted Sample
List ofall itemsin usewith itemnumber
Snapshot
1,500 items in
use
8,500 items
shelved
1,500 items in
use
Reader-Weighted Availability
500 items in use now
1,000 items not in use now
June 15 sample July 30 sample
Reader-Weighted Sample
Collection development calendar
Reader-Weighted Availability:Shelf Sample
Reader-Weighted Availability: Sample from the collection in use
Data are from the Des Moines Public Library.
Reader-Weighted Availability:Sample from the collection in use
Collection
Collection in UseNo. of items in sample Availability
% Change
Out 2/22/99
On Shelf 4/27/99 1999 1997
Young Adult 970 608 .63 n.a. n.a.
YS Nonfiction 2,611 2,069 .78 .69 9%
YS Fiction 1,148 902 .79 .77 2%
Picture Books 5,745 3,196 .56 .46 10%
J Paperbacks 1,008 616 .61 .46 15%
Audio discs 4,461 1,988 .45 .48 -3%
Reader- Mjweighted Mj
Availability Mj
Sample from MjCollection in Use Mj
Estimate from MjDemand tables Mj
Estimates from Demand Tables
Philip M. Morse. "Demand for Library Materials: An Exercise in Probability Analysis," Collection Management, 1, no. 3-4 (Fall-Winter 1976), 47-78.
Turnover
Turnover is the mean annual circulation per item of a rhizome.
Turnover
Use original circulations if possible
For all calculations involving circulation, use original circulations if possible, rather than original circulations plus renewals.
1. Collection
2.Number of Items
3.Original
Circulation4.
Turnover
5-6. Loan
Period
7.Demand per itemTable
8.Total
Demand
Picture Books 3,843 16,199 4.2 3 weeks
Board Books 407 2,536 6.2 3 weeks
Videos 1,127 10,949 9.7 1 week
DVDs 805 13,015 16.2 1 week
Audiobooks - tapes 1,005 2,327 2.3 3 weeks
Audiobooks - CDs 438 971 2.2 3 weeks
Exercise: Reader-Weighted Availability, Estimate from Demand Tables: Turnover, Demand Per Item, Total Demand
Core assumption: The mean amount of time an item is out per checkout is equal to the standard length of
loan for the item’s rhizome.
Readers visit the library on a regular schedule that is in synch with the library’s checkout periods.
Distribution of length of loansAmes Public Library 1988-89
Mean length of loan, Ames Public Library: 17.6 days
Add 3 days for reshelving: 21 days
Time since last arrival
Stanley J. Slote. Weeding Library Collections: Library Weeding Methods. 4th ed. Littleton, CO: Libraries Unlimited, 1997.
Mean Annual Days Out
𝐷𝑎𝑦𝑠𝑜𝑢𝑡=1×21=21𝐷𝑎𝑦𝑠𝑜𝑢𝑡=13×21=273
Annual time on shelf
Time on shelf = 365 – 21 = 344
Time on shelf = 365 – 273 = 92
Mean time between arrivals
= 344
𝑇𝑖𝑚𝑒𝑏𝑒𝑡𝑤𝑒𝑒𝑛𝑎𝑟𝑟𝑖𝑣𝑎𝑙𝑠=𝑇𝑖𝑚𝑒𝑜𝑛 h𝑠 𝑒𝑙𝑓𝑇𝑢𝑟 𝑛𝑜𝑣𝑒𝑟
= 7
Turnover/Time between arrivals/Annual Circulations:
Individual Items
TurnoverTime
between arrivals
Weekly circulation
Seat-of-the-pants annual
circulation
1 344 1/52 = .0192 1
13 7 1 52
Mean demand increases exponentially in relation to turnover.
Exponential increase: The rate of increase gets higher as turnover gets higher (curves upward), rather than staying the same (straight line).
0
5
10
15
20
25
30
35
40
45
50
0 2 4 6 8 10 12 14 16 18
Turnover
Me
an
De
ma
nd
Pe
r It
em
4 weeks
< 1 week1 week2 weeks3 weeks
Mean demand per item by turnoverFor standard library loan periods – groups of items
Demand tables
I have built a demand table for each standard length of loan. Use the table to look up the turnover for a rhizome and the corresponding mean demand per item. Round down if a turnover is not listed.
1. Collection
2.Number of Items
3.Original
Circulation4.
Turnover
5-6. Loan
Period
7.Demand per itemTable
8.Total
Demand
Picture Books 3,843 16,199 4.2 3 weeks 7.6
Board Books 407 2,536 6.2 3 weeks 15.8
Videos 1,127 10,949 9.7 1 week 19.2
DVDs 805 13,015 16.2 1 week 60.5
Audiobooks - tapes 1,005 2,327 2.3 3 weeks 3.1
Audiobooks - CDs 438 971 2.2 3 weeks 3.0
Exercise: Reader-Weighted Availability, Estimate from Demand Tables: Turnover, Demand Per Item, Total Demand
Estimate total demand for a rhizome (total potential circulations)
Multiply the Demand per Item times the Number of Items.
Total demand for a rhizome (from table)
1. Collection
2.Number of Items
3.Original
Circulation4.
Turnover
5-6. Loan
Period
7.Demand per itemTable
8.Total
Demand
Picture Books 3,843 16,199 4.2 3 weeks 7.6 29,207
Board Books 407 2,536 6.2 3 weeks 15.8 6,431
Videos 1,127 10,949 9.7 1 week 19.2 21,638
DVDs 805 13,015 16.2 1 week 60.5 48,703
Audiobooks - tapes 1,005 2,327 2.3 3 weeks 3.1 3,116
Audiobooks - CDs 438 971 2.2 3 weeks 3.0 1,314
Exercise: Reader-Weighted Availability, Estimate from Demand Tables: Turnover, Demand Per Item, Total Demand
Calculate Reader-Weighted Availability
Divide Original Circulation by Total Demand.
Reader-weighted availability using table
1.Collection
3.Original
Circulation
8.Total Demand(above)
Reader-
WeightedAvailability
Picture Books 16,199 29,207 .55
Board Books 2,536 6,431 .39
Videos 10,949 21,638 .51
DVDs 13,015 48,703 .27
Audiobooks - tapes 2,327 3,116 .75
Audiobooks - CDs 971 1,314 .74
Reader-Weighted Availability, Estimate from Demand Tables: Reader-Weighted Availability
Shelf Availability - Items
Duplication
Duplication Mj
Traditional Mjduplication Mjpractices Mj
Applying Mjarrival times Mj
Exercise
List the duplication practices that you have used or are aware of.
Duplication Practices
• Number of holds• Past experience with an
author or title – gut feelings – gross circulation
• Best seller lists – 2 copies if it’s on the list
• Book to movie tie-ins• High risk books• Interlibrary loans as early
indicator
• Buzz• Popular author list –
automatically yours• Popular series – at least as
many as we bought of the last volume
• Suggestions for purchase – number of people
• How it’s used – popular use/academic use
• Press runs
Applying arrival times
Always MjAvailable Mj
Lists Mj
Applying Mjarrival times Mj
Time since Mjlast arrival Mj
Return on MjInvestment Mj
Using the Mjduplication Mj
tables Mj
Annual Mjreplacement Mj
lists Mj
Time since Mjlast arrival Mj
Random Mjarrivals Mj
Exponential Mjincrease in Mj
copies Mjrequired Mj
Tool crib Mjformula Mj
7-Day Median Arrival TimeCirculations
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Weeks
Random arrival times with circulation periods
2 3 5 3 2 2 3 4 3 1 2 2
Random arrivals are approximated by the normal curve
S.D. = Standard Deviation
The Tool Crib Formula
Robert S. Grant. "Predicting the Need for Multiple Copies of Books," Journal of Library Automation 4, no. 2 (June 1971) 64-71.
Leffler, William L. "A Statistical Method for Circulation Analysis." College and Research Libraries 25 (November 1964): 488-490.
𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑐𝑜𝑝𝑖𝑒𝑠= 1+ 𝐷𝑎𝑦𝑠 𝑖𝑛 𝑙𝑜𝑎𝑛 𝑝𝑒𝑟𝑖𝑜𝑑 × 𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑐𝑖𝑟𝑐𝑢𝑙𝑎𝑡𝑖𝑜𝑛𝑠𝐷𝑎𝑦𝑠 𝑖𝑛 𝑐𝑖𝑟𝑐𝑢𝑙𝑎𝑡𝑖𝑜𝑛 𝑙𝑖𝑓𝑒
Mobil Travel Guide Study
Each additional added copy results in fewer additional circulations.
Return on MjInvestment Mj
Circulations Mjper item Mj
Browsability Mj
Mid-list titles Mj
Duplication tables for one through four week loan periods are available at:www.whatwouldranganathando.org
Always MjAvailable Mj
Lists Mj
Applying Mjarrival times Mj
Time since Mjlast arrival Mj
Return on MjInvestment Mj
Using the Mjduplication Mj
tables Mj
Annual Mjreplacement Mj
lists Mj
Always Available Lists
Brian Smith. "The Always (Almost Always) Available Book System." U*N*A*B*A*S*H*E*D Librarian, no. 5 (Fall 1972) 3.
Annual Replacement Lists
Holdings MjAvailability Mj
vs. MjShelf Mj
Availability Mj
Policy Mj
Audience MjSize Mj
Just-in-case Mjvs. Mj
Just-in-time Mj
Library MjCommunity Mj
Reader MjCommunity Mj(Rhizomes) Mj
Availability: Are the texts that the reader would prefer to select presented when the reader would prefer to select them?