Discovery or Displacement? A Large-Scale Longitudinal Study of the Effect of Discovery Systems on Online
Journal Usage
July 23, 2014
Michael Levine-Clark, University of DenverJohn McDonald, University of Southern California
Jason Price, SCELC Consortium
Why Do We Use Discovery Services?
• Too many sources of information– Specialized– Confusing– What’s the right specialized database for my
subject?
• Why do you search in one place for an article, another place for a different article, another for a book?
Terminology
Discovery Tool = Discovery Layer = Discovery Service = Discovery System
Web-scale discovery services
• Single source for finding information– Books– Articles– Local content
• Metadata and/or full text
• Content is pre-indexed and/or pre-harvested
• Single fast search
ILS
HathiTrust
MLA Bibliograph
y
Institutional Repository
Publisher Metadata
Discovery Service
Does implementation of a discovery service impact usage of publisher-
hosted journal content?
What did we measure?
• Whether there is an effect
• NOT why that effect exists (that’s a future study!)
Publisher-hosted journals are only part of the picture
eBooks, pBooks, newspaper articles, aggregator journal content, etc.
publisher journal content
The six publishers in this study
52.3
12.41
2.8
32.5
Open web searchLibrary referralsSocial mediaAcademicN/A
Journals Traffic Sources (SAGE, Conrad ALPSP 2013)
An assumption
• At any given institution, given a relatively stable user base, the total search effort will remain roughly the same.
Discovery services Will take up an increasing amount of a finite
time for searching
Will draw users from other (more or less efficient) search tools
Will alter the overall productivity of searches (users will find more or less)
Will alter the overall efficiency of users (users will access more or less full-text)
Dataset• 33 Libraries– 28 US, 2 CA, 1 each from UK, AUS, NZ
– WorldCat book holdings>Average: 1,114,193 ; Range: ~300k to ~2.6mil
– 4 discovery groups, of 6 libraries each
– 1 control group, 9 libraries• Implementation dates (Discovery Libraries):
>2010 (3), 2011 (19), 2012 (2)
• 6 Publishers• 9,206 Journals• 163,545 Usable Observations
Methodology
Compared COUNTER JR1 total full text article views for the
12 months before vs 12 months after implementation date
June
201
0St
art
Impl
emen
tatio
nM
ay 2
011
May
201
2En
d
Year 1 Year 2
Included implementation month in Year 1 to ensure that both periods included an entire academic year
Examine Data for Outliers
Analyzing Usage Change: % vs Total
Use 12 months before
Use 12 months
after% Change Total
Change
Journal A 500 600 20% 100
Journal B 5 15 200% 10
Which is the better measure?
Is it the same for publisher- & journal-level data?
Observations by Publisher
Journals by Library & Service
EDS Primo Summon WorldCat Control
Average Journal Usage by Library
Testable Effects
• Discovery Tool– Implemented by multiple libraries– Used to find content from all publishers
• Publisher– Accessible in all discovery tools– Accessible across multiple libraries
• Library– Uses content from multiple publishers– Uses only one discovery tool (so only within
DT)
Full Model
Including Discovery Service, Publisher, and Library
Including Discovery Service, Publisher, and Library
Nested ANOVA Model Results
How does usage change differ across discovery services?
ABB
C
D
Letters indicate statistically significant differences (Tukey multiple comparisons, p < .05)
How does usage change differ across publishers?
Publisher (sorted by Mean Change)
C
Letters indicate statistically significant differences (Tukey multiple comparisons, p < .01)
D
BBB
A
How does usage change differ across publishers?
Does usage change vary across libraries?
Institution (sorted by Mean Change)
Usage Change Per Institution: All Journals
Control EDS Primo Summon WCL
Usage Change By Institution: Pub 16.32
Primo WCLSummonEDSControl
Usage Change By Institution: Pub 2
Control EDS Primo Summon WCL
Usage Change By Institution: Pub 3
WCLEDS PrimoControl Summon
Usage Change By Institution: Pub 4
WCLEDSControl Primo Summon
Usage Change Per Institution: Pub 5
Control EDS Primo Summon WCL
Usage Change by Institution: Pub 6
WCLSummonPrimoEDSControl
Publisher 1 by Discovery System
Publisher 2 by Discovery System
Publisher 3 by Discovery System
Publisher 4 by Discovery System
Publisher 5 by Discovery System
Publisher 6 by Discovery System
Next Steps• Design & test for effects of:
–Aggregator full text availability–Journal age (archive vs current)–Journal Subject–Overall usage trends–Configuration options in Discovery services
• Expand pool of libraries• Perhaps explore WHY
Sharing Data• With participating libraries
–Customized reports for each library
• With participating publishers–Customized reports for each publisher–Presentations as requested
• With discovery vendors–Presentations as requested
• In publications and presentations–Maintaining anonymity of data
Presentations• Ithaka Sustainable Scholarship Conference (October 2013)• Charleston Conference (Nov 2013) http://sched.co/17A3Kun
• ER&L/Library Journal Webinar (December 2013)• Shangai Jiao Tong Univ / Beijing Univ Forum (Jan 2014)• SCELC Colloquium (March 2014) http://goo.gl/WmJoIw
• ER&L (Mar 2014) http://bit.ly/discovery-impact-erl2014 • UKSG (April 2014) https://www.youtube.com/watch?v=d_2ycMk_9fA
• Presentations to three publishers (Spring-Summer 2014)–More to come