FAQ
- What are Article-Level Metrics?
- What is the Article-Level Metrics Application?
- Can I run my own Article-Level Metrics Application?
- What is the Article-Level Metrics API?
- How does PLoS use the Article-Level Metrics API?
- Are there any examples using the Article-Level Metrics API?
- Recommended Usage of the Article-Level Metrics API
- How do I request a PLoS API key?
- How do I use the PLoS API key?
- I have questions about using the PLoS Article-Level Metrics API. Where can I get answers?
What are “Article-Level Metrics”?
Starting in March 2009, PLoS became the first publisher to place transparent and comprehensive information about the usage and reach of published articles onto the articles themselves, so that the entire academic community could assess their value. We call these measures for evaluating articles Article-Level Metrics and they are distinct from the journal-level measures of research quality that have traditionally been made available. By placing the relevant data on each journal article, users can determine the value of that article to them and to the scientific community in general.
What is the Article-Level Metrics Application?
The Article-Level Metrics Application is an Open Source application that stores and reports performance data on research articles. PLoS uses this application to aggregate relevant data and statistics for research articles including online usage, citations, social bookmarks, notes, comments, ratings and blog coverage.
Can I run my own Article-Level Metrics application?
You sure can! The Article-Level Metrics application is Open Source and developed in Ruby. The source code is available for download at the Article-Level Metrics Google Project site.
What is the Article-Level Metrics API?
The Article-Level Metrics API gives developers access to the data collected by the Article-Level Metrics application for every article published in the PLoS journals and for every article added to PLoS Hubs: Biodiversity. With the Article-Level Metrics API, you can retrieve:
- The usage statistics for HTML page views, PDF downloads and XML downloads from PLoS and PubMed Central.
- The number of citations an article has received from CrossRef, PubMed Central and Scopus.
- Activity on social networks such as Twitter, Mendeley, Facebook, Connotea and CiteULike.
- Blog coverage from Nature Blogs and Research Blogging.
For a complete list of the sources used, please see the Article-Level Metrics Sources.
How does PLoS use the Article-Level Metrics API?
PLoS uses the Article-Level Metrics API to retrieve the usage statistics, citation counts, number of bookmarks and number of blog mentions for every article published in the PLoS journals and for every article added to PLoS Hubs: Biodiversity. We then use the Article-Level Metrics API to graph the usage statics using Dojo JavaScript library and display the counts for the other metrics. You can see examples of Article-Level Metrics in action on the PLoS Biology article Viral Discovery and Sequence Recovery Using DNA Microarrays.
For a complete description of the data acquired by PLoS, please see the Article-Level Metrics Information guide .
Are there any examples using the Article-Level Metrics API?
Sure are! We have a number of examples using the Article-Level Metrics API.
Recommended Usage of the Article-Level Metrics API
- Content Attribution: Developers are welcome to make use of the data returned from the PLoS Article-Level Metrics API and we ask that you indicate that the data originate from PLoS. If you wish to brand your work to PLoS, you will need to ask us to evaluate the usefulness and technical capability of your application prior to receiving a PLoS logo which you may then display on the application. Please see the API display policy for more information.
- PLoS Article-Level Metrics API rate limit: Please limit your API requests to 1000 requests a day and allow 5 seconds for your query to return results. If you exceed this threshold, we will lock out your IP address. If you’re a high-volume user of the PLoS Article-Level Metrics API and need more API requests a day, please contact us at api@plos.org to discuss your options. We currently limit API users to no more than five concurrent connections from a single IP address.
- PLoS Article-Level Metrics API requests: Please do not send requests that return data for all articles tracked by Article-Level Metrics. That’s a lot of data for our network to push all at once and it may take some time to return the result set. If you need the entire data set for all articles tracked by Article-Level Metrics, please download this summary Excel file.
How do I request a PLoS API key?
Just browse on over to registration and fill out the form. Your PLoS API key will be emailed to you.
How do I use the PLoS API key?
Any request made to the PLoS API must include the argument api_key=[your PLoS API key]. That’s it!
I have questions about using the PLoS Article-Level Metrics API. Where can I get answers?
If you have any questions or comments about the Article-Level Metrics application, head over to the PLoS API Community page for information on the PLoS API developers group.