Citations are the currency of academia. Scholars who manage to gain a lot of them are more likely to get promoted, more likely to win prestigious awards and more likely to win the respect of their peers. An academic with a lot of citations is kind of like a City banker with a large end-of-year bonus – a big deal.

Given the importance attached to citation counts, scholars have an incentive to boost theirs by any means necessary. One practice that has received significant attention is self-citations. This is where individuals make a disproportionate number of citations to their own work. Another, related phenomenon is citation cartels. These refer to groups of individuals who agree to make a disproportionate number of citations to each other’s work.

Individuals who boost their citation counts through underhand practices obviously gain an unfair advantage over those who play by the rules. Hence there is considerable interest in detecting such practices, which are collectively termed ‘citation manipulation’.