This paper studies the citation decision of a scientific author. When an author can make
his argument more persuasive by citing a related work, this is called the correlation effect.
On the other hand, when an author cites someone else’s work, he gives the impression that he
views the cited author as more competent than himself; this is called the signaling effect.
These two effects are the main causes of citation bias. Using data from Research Papers in
Economics or RePEc, a decentralized database of working papers, journal articles and
professional books, we empirically show that a citation bias exists in this field. The empirical
finding is obtained by controlling for many variables that affect citation patterns, such as
network factors (co-authorship and an author’s affiliation) and language.