As a means of making available and acquiring e-books, Stockholm University Library uses PDA and EBS models. In order to improve the knowledge of the benefits and drawbacks of these purchasing models, the library has undertaken a major evaluation of ten agreements with various publishers and aggregators. This session will, among other things, address the following questions: What is the average price per book at the time of purchase? What is the cost per use? Do purchased titles continue to be used? What is the usage by subject area and by year of publication?

1. Evaluation of PDA and EBS
models for e-books at
Stockholm University Library
UKSG 40th Annual Conference April 2017, Harrogate
2017-04-10 /Frida Jacobson, Stockholm University Library

2. Agenda
● Stockholm University and the University Library
● Patron-driven acquisition strategy
● PDA and EBS models
● Evaluation
● Findings
● Conclusions

3. Stockholm University
● Founded in 1878 – a free and radical college
● One of the largest universities in Sweden
● Science, Humanities and Social Sciences
● 70,000 students (28,000 FTE, 63% women)
– 12% Science, 88% HSS
● 1,700 doctoral students (50% women)
– 47% Science, 53% HSS
● 5,000 employees
– 450 professors (30% women)

4. Stockholm University Library
● Number of employees
– 115 (librarians, IT and economy staff, HR)
● Media acquisition budget
– approx. 4,8 million EUR (46 million SEK)
– 94 % e-resources, 6 % print
● Ebooks
– Access to approx. 800,000 e-books

5. Strategy for Stockholm University Library’s
patron-driven acquisiton
● Providing users with quick access to requested
media resources – anytime and anywhere
● From just-in-case to just-in-time acquisition model
● Users drive acquisition through
– purchase suggestions
– usage
– PDA/EBS models

6. PDA and EBS models
● Upfront payment to a publisher or aggregator
● Access to a large number of unowned e-books
● Accessible via library catalogue and e-book platform
● Access for a certain period of time, often a year
● The most used ebooks are purchased and owned – with
help of ’triggers’ or usage statistics
● Only e-books with proven usage are purchased
● Core idea – purchased e-books will continue to be used

7. Evaluation
Description and experiences
o Content
o Pricing model
o Accessibility
o Work input
o Support
Cost and usage analysis
o Cost
o Usage

8. Cost and usage analysis
● What is the average price per book at the time of purchase?
● What is the cost per download?
● How great a proportion of the titles is used?
● How great a proportion of the titles is purchased?
● Do purchased titles continue to be used?
● Usage by subject area?
● Usage by year of publication?

9. Method – cost and usage analysis
Yr 3Yr 2Yr 1Selection
period

10. PDA and EBS models from 2 aggregators
and 8 publishers were tested
Publisher / Aggregator Number of titles
Academic Video Online 43,000 (videos)
Brill* 4,600
Cambridge University Press 30,000
De Gruyter 33,000
Ebrary (aggregator) 140,500
EBSCO (aggregator) 60,000
Oxford Scholarship Online 11,600
Palgrave* 3,700
Wiley 18,000
Taylor and Francis: CRCnetBASE 9,400
*Less titles since SUB already owns subject collections from these publishers
310 800
e-books
in total

11. The vendors’ average price per e-
book varied
Publisher/aggregator Average price per title EUR
Publisher A (videos) 14
Publisher B period 1-2 103
Publisher B period 3 100
Publisher C period 1-4 107
Publisher C period 5 132
Publisher D 178
Publisher E period 1 192
Publisher E period 2 160
Publisher E period 3 129
Aggregator A 87
Aggregator B 278
Publisher F 177
Publisher G 99
Publisher H period 1 89
Publisher H period 2 79
Publisher H period 3 111
Publisher H period 4 118
Average price per title all models 127

12. Cost per download after purchase falls
Publisher / aggregator
1 yr after
purch. EUR
2 yrs after
purch. EUR
3 yr after
purch. EUR
4 yrs after
purch. EUR
Publisher A (videos) 880
Publisher B 119
Publisher C period 1 19 10 7 5
Publisher C period 2 22 12 8
Publisher C period 3 12 7
Publisher D 73
Publisher E period 1 49 25
Publisher E period 2 27
Aggregator A 1 1
Aggregator B 69
Publisher F 9
Publisher G 8
Publisher H period 1 7 3 2
Publisher H period 2 10 5

13. (
YEAR
1
YEAR
2
YEAR
3
YEAR
4
19 10 7 5Publisher C
Period 1
27 3Publisher H
Period 1
Cost per download falls (EUR)

14. Proportion of used titles and purchased
titles differ
Publisher Proportion of used titlesProportion of purch. titles
Publisher A (videos) 1% 15%
Publisher B period 1-2 23% 9%
Publisher B period 3 12% 4%
Publisher C period 1 15% 11%
Publisher C period 2 14% 6%
Publisher C period 3 14% 6%
Publisher C period 4 16% 7%
Publisher C period 5 19% 5%
Publisher D 10% 12%
Publisher E period 1 3% 2%
Publisher E period 2 5% 1%
Publisher E period 3 9% 1%
Publisher F 14% 2%
Publisher G 29% 9%
Publisher H period 1 18% 5%
Publisher H period 2 17% 6%
Publisher H period 3 13% 4%
Publisher H period 4 16% 5%

15. USED
%
PURCHASED
%
1
15
Publisher A
12
10
Publisher D Publisher H
period 1
18
5
Publisher C
period 1
15
11
Usage vs purchase – two examples

16. Purchased titles continued to be used
Publisher /aggregator
Proportion
of used titles
yr 1
Proportion
of used titles
yr 2
Proportion
of used titles
yr 3
Proportion
of used titles
yr 4
Proportion
of used title
yr 5
Publisher A (videos) 1%
Publisher B period 1-2 34%
Publisher C period 1 38% 51% 60% 67% 71%
Publisher C period 2 30% 46% 55% 61%
Publisher C period 3 42% 56% 64%
Publisher C period 4 38% 53%
Publisher D 21%
Publisher E period 1 34% 48%
Publisher period 2 38%
Aggregator A 68% 61%
Aggregator B 35%
Publisher F period 1 59%
Publisher G 63%
Publisher H period 1 54% 69% 75%
Publisher H period 2 53% 69%
Publisher H period 3 26%

17. YEAR
1
YEAR
2
YEAR
3
YEAR
4
YEAR
5
Proportion of used titles in %
7138
Publisher C
period 1 51 60 67
Publisher H
period 1 54 69 75

18. Humanities and social science were
popular subject areas
Linguistics and Semiotics
47%
Literary Studies
16%
Law
7%
Philosophy
10%
Classical Studies…
Social Sciences
3%
Theology and Religions Studies
6%
History
2%
Architecture, Art, Music
2%
Mathematics
1%
Library & Information Science…
Other
1%
de Gruyter: used titles by subject – period 1

19. 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Social & Behavioral Sciences (42 titles)
Humanities (78 titles)
Mathematics & Statistics (176 titles)
Business, Economics, Finance & Accounting (46 titles)
Life Sciences (28 titles)
Medicine (11 titles)
Various subjects (25 titles)
Psychology (26 titles)
Earth, Space & Environmental Sciences (33 titles)
Computer Science & Information Technology (14 titles)
Chemistry (153 titles)
Physical Sciences & Engineering (105 titles)
Agriculture, Aquaculture & Food Science (11 titles)
90%
91%
82%
70%
61%
27%
64%
69%
58%
50%
55%
44%
36%
7%
1%
6%
7%
14%
45%
8%
0%
9%
14%
8%
12%
9%
2%
8%
11%
24%
25%
27%
28%
31%
33%
36%
37%
44%
55%
Wiley: Usage per subject 3 years after purchase (748 titles)
Titles used more than once Titles used only once Titles without usage

20. Usage stats indicates new interesting subject
areas
Asian Studies
23%
Biblical Studies
20%
Social Sciences
11%
History
11%
International Law
10%
Middle East & Islamic
Studies
9%
Language & Linguistics
8%
Human Rights &
Humanitarian Law
3%
Classical Studies
3%
Biology
2%
Materials & Surface
Science
0%
Brill: used titles – by subject

21. The most recently published titles have
been used the most
1990-2006
1%
2007-2009
11%
2010-2012
44%
2013-2015
44%
de Gruyter: used titles by year of publication – period 3

22. Summary cost and usage analysis
● The vendors’ average price per e-book varied
● Cost per download falls over the years
● Purchased titles continued to be used
● Social sciences and humanities were popular subject areas
● Recently published titles have been used the most
● Collected statistics are useful for future subject collections
purchases
● Two EBS models were not successful regarding cost and usage

23. ● One large publisher
● Less titles
● Access to all content, no STL*
● Purchase based on usage stats
● No DRM**-restrictions
● Unlimited number of users
● Less labour intensive
● Control over the money invested
PDA from aggregators EBS from publishers
*STL=Short Term Loan, *DRM=Digital Rights Managements
● Many different publishers
● Large number of titles
● Selection profiles, STL*
● ”Triggers” lead to purchase
● DRM**
● Limited number of users
● Labour intensive
● Invested money spent fast

24. Next steps
● Update the 2016 figures for all agreements
– titles continued to be used
– per year and subject area
● Perform a usage analysis of traditionally purchased e-book
packages
● Test more EBS models from publishers
● When deselect a successful EBS model where we own
a large part of the content on the platform?
● If not continue with EBS – what would then be the
alternatives?

25. Any questions?
Thank you for your attention.
Contact: frida.jacobson@sub.su.se
2017-04-10 /Frida Jacobson, Stockholm University Library