  Although there are a number of social networking services that specifically
target scholars, little has been published about the actual practices and the
usage of these so-called academic social networking services (ASNSs). To fill
this gap, we explore the populations of academics who engage in social
activities using an ASNS; as an indicator of further engagement, we also
determine their various motivations for joining a group in ASNSs. Using groups
and their members in Mendeley as the platform for our case study, we obtained
146 participant responses from our online survey about users' common
activities, usage habits, and motivations for joining groups. Our results show
that 1) participants did not engage with social-based features as frequently
and actively as they engaged with research-based features, and 2) users who
joined more groups seemed to have a stronger motivation to increase their
professional visibility and to contribute the research articles they had read
to the group reading list. Our results generate interesting insights into
Mendeley's user populations, their activities, and their motivations relative
to the social features of Mendeley. We also argue that further design of ASNSs
is needed to take greater account of disciplinary differences in scholarly
communication and to establish incentive mechanisms for encouraging user
participation.
