Levine-Clark, Michael “Diving into eBook Usage: Assessing the Swell of Information,” Electronic Resources & Libraries, Austin, March 17, 2014

Diving Into E-Book Usage: Navigating the Swell of Information

ER&LAustin

March 17, 2014

Michael Levine-ClarkAssociate Dean for Scholarly Communication and Collections Services

University of Denver Libraries

What can we learn by examining usage of 750,000+ e-books?

• Does quality matter?• Are there general patterns by subject?• Can we identify disciplinary preferences?• What are the best ways to measure use?• Can those patterns and preferences help

shape our collections and guide our services?

Coming Soon: More data, with more solid

conclusions

The Data Set

• 2010– 435,417 titles– 5,295 libraries



• 2013 (through Sept 4)– 776,060 titles– 7,118 libraries

• 2011– 225,448 titles– 291 libraries

• 2012– 320,796 titles– 411 libraries

• 2013 (through Sept 9)– 378,530 titles– 587 libraries

Combined Data

• 2010-Sept 2013• 435,417 titles• 304,417 with an LC call

number• 32,988 university press

titles

• 2011-Sept 2013• 217,457 titles• 210,539 titles with an LC

call number• 21,089 university press

titles

Usage Definitions• Session– Any time that a user interacts with an e-book

• View– A count of the number of pages examined

• Download– A download of the entire book

Some aspects of usage aren’t comparable

• ebrary has far more libraries than EBL, and an extra year of data– Averages and totals only useful when comparing

within one aggregator• There may be some platform differences that

drive usage in different ways:– More downloads on EBL = fewer pages viewed

Call Numbers

• Assigned to some books, but not all• More for EBL than ebrary• Call numbers may be inconsistently applied– Will soon have set with combined titles and single

call number

Breadth vs Depth

PERCENTAGE OF TITLES USED

AVER

AGE

AMO

UN

T O

F U

SE

DO HIGHER-QUALITY E-BOOKS GET USED MORE?

University Press Books

• A proxy for quality• ebrary – 32,988 titles• EBL – 21,089 titles

Do better books get used at a higher rate?

Overall Usage: titles with at least one session

ebrary EBL0.00%

10.00%20.00%30.00%40.00%50.00%60.00%70.00%80.00%90.00%

100.00%

69.61%

88.33%91.72% 89.00%93.76% 93.80%

All Titles Titles with LC Call NumberUniversity Press Titles

Overall Usage: average sessions per title

across all libraries

ebrary EBL0

50

100

150

200

250

300

350

400

147.43

69.39

208.64

70.99

339.01

76.74


Overall Usage:titles viewed at least once

ebrary EBL0.00%

10.00%20.00%30.00%40.00%50.00%60.00%70.00%80.00%90.00%

100.00%

69.15%

87.30%91.70% 88.01%

93.74% 92.82%


Overall Usage: average page views per title


ebrary EBL0

1000

2000

3000

4000

5000

6000

2245.23

1310.39

3174.31

1341.91

5203.82

1499.78


Overall Usage: titles with at least one full download

ebrary EBL0.00%

10.00%

20.00%

30.00%

40.00%

50.00%

60.00%

70.00%

80.00%

24.35%

59.12%

34.42%

59.83%

40.12%

67.77%


Overall Usage: average downloads per title


ebrary EBL0

2

4

6

8

10

12

2.77

9.34

3.95

9.54

5.64

10.41


University Press Summary

• Used at a higher rate across all categoriesBUT

• University press books may be available in more libraries

BROAD DISCIPLINARY DIFFERENCES

The Disciplines

HumanitiesB (Philosophy, Religion) excluding BF (Psychology)C, D, E, F (History)M (Music)N (Fine Arts)P (Language & Literature)

Social Sciences BF (Psychology)H (Social Sciences)J (Political Science)K (Law)L (Education)U, V (Military, Naval Sciences)

STEMQ (Science)R (Medicine)S (Agriculture)T (Technology)

Percentage of Titles Usedebrary

Discipline % Titles with a Session

% Titles Viewed % Titles Downloaded

Humanities 92.05% 92.04% 40.87%

Social Sciences 92.70% 92.69% 36.40%

STEM 90.19% 90.17% 27.53%

Baseline (all titles with an LCCN) 91.72% 91.70% 34.42%

Percentage of Titles UsedEBL

Discipline % Titles with a Session

% Titles Viewed % Titles Downloaded

Humanities 88.44% 87.19% 58.62%

Social Sciences 89.95% 89.12% 62.40%

STEM 88.30% 87.35% 57.68%

Baseline (all titles with an LCCN) 89.00% 88.01% 59.83%

Average Usageebrary

Discipline Sessions Page Views Full Downloads

Humanities 207.79 3122.16 3.95

Social Sciences 251.21 3766.11 4.74

STEM 162.57 2570.70 3.16

Baseline (all titles with LCCN) 208.64 3174.31 3.95

Average UsageEBL

Discipline Sessions Page Views Full Downloads

Humanities 54.18 999.12 6.76

Social Sciences 91.96 1694.91 12.54

STEM 59.90 1192.46 8.32

Baseline (all titles with LCCN) 70.99 1341.91 9.54

Actions Per Sessionebrary

Discipline Views Per Session Downloads Per Session

Humanities 15.03 0.019

Social Sciences 14.99 0.019

STEM 15.81 0.019

Baseline (all titles with an LCCN) 15.21 0.019

Actions Per SessionEBL

Discipline Views Per Session Downloads Per Session

Humanities 18.44 0.125

Social Sciences 18.43 0.136

STEM 19.91 0.139

Baseline (all titles with an LCCN) 18.90 0.134

Disciplinary Summary

• Social sciences far outperform humanities and STEM in two categories– Percentage of books used– Average amount of use

• Humanities stronger than STEM on ebrary• STEM stronger than humanities on EBL• STEM outperforms the others in actions per

session

MEASURING PREDICTED USE

Difference from Predicted UseLC Class % of eBooks

available% of titles with a session

Difference

A – General Works 0.19% 0.19% 0.00%

B – Philos, Psych, Religion 7.03% 6.88% -0.16%

C – Aux Sciences of History 0.40% 0.41% +0.01%

D – World History, etc. 3.70% 3.73% +0.03%

E – History of the Americas 1.65% 1.71% +0.06%

F – History of the Americas 1.96% 1.85% -0.11%

G – Geog, Anthro, Rec 2.94% 3.01% +0.07%

H – Social Sciences 21.98% 22.27% +0.29%

J – Political Science 3.40% 3.50% +0.10%

K – Law 3.33% 3.29% -0.04%

Difference from Predicted UseLC Class % of eBooks

available% of titles with a session

Difference

L - Education 4.61% 4.80% +0.19%

M - Music 0.81% 0.85% +0.04%

N – Fine Arts 1.06% 1.10% +0.04%

P – Language & Literature 10.87% 11.00% +0.13%

Q - Science 13.09% 12.51% -0.58%

R - Medicine 10.83% 10.73% -0.10%

S - Agriculture 2.01% 2.08% +0.07%

T - Technology 8.65% 8.69% +0.04%

U – Military Science 0.69% 0.58% -0.11%

V – Naval Science 0.12% 0.12% 0.00%

Z – Bibliography and LIS 0.67% 0.69% -0.02%

% of titles used (breadth)

% of titles used (breadth)

% of overall usage (depth)

% of overall usage (depth)

Performance Compared to Expected Use

Better than expected (top five)

• H (Social Sciences)• L (Education)• G (Geography,

Anthropology, Recreation)• N (Fine Arts)• D (World History)

Worse than expected (bottom five)

• Q (Science)• F (History of the Americas)• P (Language & Literature)• K (Law)• U (Military Science)

INTENSIVE / EXTENSIVE USE

ebrary Sessions – Avg and % Narrow (low %) but Deep (more usage of each title)

Broad (high %) andDeep (more usage of each title)

Narrow (low %) andShallow (low usage of each title)

Broad (high % and Shallow (low usage of each title)

EBL Sessions – Avg and % Narrow (low %) but Deep (more usage of each title)




ebrary Page Views – Avg and % Narrow (low %) but Deep (more usage of each title)




EBL Page Views – Avg and % Narrow (low %) but Deep (more usage of each title)




ebrary Downloaded – Avg and % Narrow (low %) but Deep (more usage of each title)




EBL Downloaded – Avg and % Narrow (low %) but Deep (more usage of each title)




CAN WE DETERMINE LEVEL OF IMMERSION IN A BOOK?

If more pages are viewed per session in a subject area, does that mean that users spend more time in those books?

Page Views Per Session - ebrary

T F E Q R C G H D N J M P B K L U A S V Z10.00

11.00

12.00

13.00

14.00

15.00

16.00

17.00

18.00

15.21

Page Views Per Session - EBL

F N T R M A E Q G C H D S B K P V J L Z U10.00

12.00

14.00

16.00

18.00

20.00

22.00

24.00

18.90

Average Rank Across Both Aggregators: Page Views Per Session

1. F – History, Americas2. T – Technology3. R – Medicine4. E – History, Americas5. N – Fine Arts6. Q – Science7. C – Aux Sciences of History8. G – Geography,

Anthropology, Recreation9. M – Music10. H – Social Sciences

11. D – History, World, etc.12. A – General Works13. B – Philos, Psych, Religion14. J – Political Science15. P – Language & Literature16. K – Law17. S – Agriculture18. L – Education19. V – Naval Science20. U – Military Science21. Z – Bibliography and LIS

CONCLUSIONS

There are many ways to measure use

• Difference from predicted use• Depth vs breadth– Books used a lot vs a lot of books used

• Type of use (session, view, download)• Amount of use per session– Does this measure amount of time spent?

Quality matters (maybe)

• University press books used at a higher rate by all measures

• Users appear to be making some judgment about quality

• But, UP books may be available in more libraries

There are clear (but nuanced) differences by subject

• Two examples– F (History, Americas) • Low usage as % of available F titles• Low average usage rate• Very poor performance relative to availability of F titles• Highest # of page views by session

– L (Education)• High usage as % of available L titles• High average usage rate• Very strong performance relative to availability of L titles• Very low # of page views by session

How do we use these observations to build better collections and

better serve our users?

White Paper

• Coming soon• Combined data set across both platforms• Analysis by– Date of publication– Length of time in the book

• More (and better?) call numbers

For More Information…

• The white paper will be available on the ebrary and EBL websites this spring

• This presentation is available on SlideShare:http://www.slideshare.net/MichaelLevineClark

http://www.slideshare.net/MichaelLevineClark



Thank You

Michael Levine-ClarkAssociate Dean for Scholarly Communication and

Collections ServicesUniversity of Denver [email protected]