How We Collect Our Readership Statistics

You might have noticed that we provide readership data for each of our books online, including the number of times each book has been viewed and the location of the readers. If you would like to know more about how this data is collected and where it comes from, read on!  

Our readership data is composed of different measures obtained from different platforms:

Platform

Measure

Geographic information

OBP HTML Reader

Book Sessions

Yes

OBP PDF Reader

Book Sessions

Yes

OBP Downloads

Book Downloads

No

Google Books

Book Sessions

No

Open Edition

Book Visits

No

Unglue.it

Book Downloads

No

Classics Library

Book Sessions

Yes

Internet Archive

Book Visits

No

OBP PDF Downloads

Book Downloads

No

Google Play Books

Book Downloads

No

Kindle

Book Downloads

No

World Reader App

Book Visits

Yes

World Reader Web

Book Visits

No



A Book Session is a group of visits made by the same user within a continuous time frame. To record these sessions we use Google Analytics, and a session lasts until there are 30 minutes of inactivity; if a single user keeps interacting with the website within this time frame, multiple visits to the same book will be counted as one session. For more information on Google Analytics’ definition of a session read: How a web session is defined in Analytics

It is important to note that we use Google Analytics’ measure for a Book Session rather than an alternative such as COUNTER, because Google Analytics has a stricter measure for the length of a Book Session. COUNTER has a much shorter time frame for a single Session, and therefore records more Sessions than Google Analytics. We do collect data for our books that would meet COUNTER's measures, but we don’t record it publicly. For more information about COUNTER see: https://www.projectcounter.org/ 

For more information on how Google Books records traffic, click here.

Book Visits represent the total number of times a book has been accessed. This can include multiple visits by the same IP address, which are counted as separate visits. 

Book Downloads represent the total number of times a book has been downloaded. In addition to the download data we receive from Unglue.it, we collect free ebook download data from other platforms including our own website, Kindle, Google Play, etc, and we add these into the statistics we report. However, these download figures are calculated slightly differently on each platform, depending on whether repeat downloads to the same IP address in quick succession are counted as two downloads or one. As with Book Sessions, we err on the side of the lower figure wherever possible.

Geographic information: most platforms do not provide geographic information about the users accessing their content, and some people configure their browsers to block any third party tracking scripts attempting to collect such information (e.g., Google Analytics). For these reasons we are only able to provide readership data by country for a small percentage of our total figures - about 12%.

We try to provide as complete a picture as possible about the number of times our books have been freely accessed, as well as the location of the readers, because this information helps to demonstrate the value of Open Access publishing. For more about what we can learn from our readership data, see our blog post.