2. What is PDA / DDA?
• A new model of purchasing solely based
on user demand
– Just in time
• Traditional purchasing model
– Just in case
3. Why PDA?
• Only buy e-books that users want
• Don’t buy e-books nobody uses
• Students can decide what to buy for the
library – not lecturers or librarians
• Build up a critical mass of e-books
available via the library
• Wider selection of reading material than
the library can hold
5. PDA at Bangor
• Working with Ebook Library (EBL)
• First trial
– October 2010 – February 2011
– Ended when money ran out!
• Second trial
– October 2011 – ?
– Until money runs out!!
6. How PDA works
• Loaded 80k MARC records from EBL
• Selected from 200k+ titles based on
publisher, date, language, price
• Users don’t know these e-books are not
owned by the library… yet
• First 3 uses treated as short term loans
• 4th access triggers a purchase
7. PDA at Bangor
• E-books are clearly marked in the
catalogue
• Access is not mediated
• After 5 mins of free browsing users are
asked if they want to continue
• After confirming users have access to the
e-book for 24 hours
• Unlimited simultaneous use (almost)
8.
9.
10.
11.
12.
13.
14. Some early findings
• Purchased 541 e-books through PDA in
12 months
• 1/3 of e-books bought through PDA are
titles we already hold in print
• 10% of e-books bought through PDA are
recommended course reading material
15.
16. E-book is more cost effective
• 5 print copies bought at £102.78
– Checked out 12 times this academic year
– Checked out 30 times last academic year
• E-book outright purchase at £27.62
– Accessed 66 times this academic year
– Accessed 199 times last academic year
– 3 x short term loans + purchase today would
have cost £56.60
17. PDA pricing
• Purchase e-book at list price + VAT
• Short term loan : 5~20% of list price
• PDA purchase = 115~160% of list price
• If 1 or 2 uses pay 5~40% of list price
• Pay nothing if a title is not used
18. Auto-purchased e-books
• Used more often than e-books bought
before PDA
• Between October 2010 & September 2011
– Average unique access to auto-purchased
titles : 16.3
– Average unique access to already owned
titles : 4.8
19. Number of access 2010 & 2011
7000
6000
5000
4000
2010
3000 2011
2000
1000
0
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20. Number of access 2010 - 2012
7000
6000
5000
4000
2010
3000 2011
2012
2000
1000
0
21. PDA vs outright purchase
• Estimated cost if all titles accessed were
purchased upfront : £404,385
• Estimated cost if all titles accessed more
than 5 mins were purchased : £229,318
• Actual PDA expenditure £69,303
• Average short term loan cost : £5.97
• Average cost of auto-purchase : £52.17
22. Challenges
• How to manage demand
• Supplementary selection method
• Sustainable PDA model?
• Consortium arrangement?
• Should we mediate more?
• PDA of e-books is here to stay
• Enhance student experience!
