Here at Mendeley, we love the efforts our Advisors and users go to, to help us improve. Following on from our  March 2015 Advisor of the Month, Huiqin Gao (Wuhan University, China) writes today’s guest blog post and gives us a summary of her investigation into paper sharing in Mendeley’s public groups.

On the Mendeley website, registered users can create or join groups. If a group is set up as “open” or “invite-only”, instead of “private”, then it is a publicly-visible group. Member and paper lists of a public group is visible to any user, including non-members, who visits it. From the perspective of information accumulation, Mendeley’s public groups become valuable resources as a starting point for seeking people and materials.

So how ‘valuable’ are these groups?
The measurement of evaluating information resources is defined as informetrics in studies of information science. I quantitatively researched Mendeley’s groups in aspect of papers, and used a novel method of informetrics – altmetrics – to measure groups’ literature values.

Data collection was conducted in June 2014 with a Python-coded web crawler. A total of 106,156 public groups were extracted, and 5,034,736 papers (including duplications) from within those groups. Some interesting findings are detailed below.

Sizes and distributions
Almost 2/3 of the groups had only one member. It is common sense that one group has to have at least one member: the creator himself. However,2/3 groups have attracted no other members. The reason for this is unknown, but maybe the creator stopped curating and managing the group after creating it.

The largest group has 1,170 members. Its name was ‘Qualitative Research Methodology’. It is a multi-disciplinary group of ‘Business Administration’ ‘Management Science / Operation Research’ and ‘Social Sciences’. This group may have so many members because qualitative methodology could be applied to many fields of research, so there are a lot of people interested in being a member.

Amazingly, one of Mendeley’s public groups has as many as 90,458 papers. This group, named ‘Vaccine 2’, is under the discipline of ‘Biological Science’. That’s not strange because on Web of Science, biology, chemistry and medicine are the disciplines that have largest number of papers. Since so many publications are produced, they are also rich resources on Mendeley.

Disciplinary differences
I counted the group numbers of each discipline, and the top five are listed below. It’s not unusual to find biology and medicine here, because they have abundant resources of publications.  Computer and engineering are disciplines highly involved with the internet, so it’s quite convenient for them to base communications on Mendeley’s groups. Social sciences is a discipline widely intersected with other disciplines, and therefore it has a large user population, and thus accounts for so many groups.

Most valuable groups
In my research, I defined ‘Average Readership (AR)’ to evaluate groups. This value is similar to the ‘Impact Factor’ that is used to measure influences of journals. But in my study, a high AR doesn’t mean high influence. Groups are not the only way people could access a paper, and therefore groups are just accumulations of papers. The higher a group’s AR, the more likely it is a valuable accumulation.

The calculation of groups’ AR value could be used as a dimension of ranking criteria of Mendeley’s search engine. Currently on Mendeley, there seems to be no other ranking rules except text relevance. For group searching on Mendeley, if you can identify highest AR groups by the first glance, you will save lot time scrolling down and jumping among pages before you decide which group to click on.

The full-text, open-access version of Huiqin’s article can be accessed directly here, or indirectly via this IDEALS webpage.