  Peer assessment has been widely studied as a replacement for traditional
evaluation, not only by reducing the professors' workload but mainly by
benefiting students' engagement and learning. Although several works
successfully validate its accuracy and fairness, more research must be done on
how students' pre-existing social relationships affect the grades they give
their peers in an e-learning course. We developed a Moodle plugin to provide
the platform with peer assessment capabilities in forums and used it on an MSc
course. The plugin curated the reviewer set for a post based on the author's
relationships and included rubrics to counter the possible interpersonal
effects of peer assessment. Results confirm that peer assessment is reliable
and accurate for works with at least three peer assessments, although students'
grades are slightly higher. The impact of social relationships is noticeable
when students who do not like another peer grade their work consistently lower
than students who have a positive connection. However, this has little
influence on the final aggregate peer grade. Our findings show that peer
assessment can replace traditional evaluation in an e-learning environment
where students are familiar with each other.
