Echo Chambers

duketheuninteresting reviews a paper, How citation distortions create unfounded authority: analysis of a citation network, by Steven A Greenberg, a professor of neurology at Harvard Medical School. duke writes (scatterplot):

In short, Greenberg identifies several mechanisms that can impair the ability of the scientific process to reach an accurate result. “Citation Bias” is the preferential citation of supporting evidence (whatever supporting is in your case) and the discounting or ignoring of critical evidence. This is particularly the case with critical primary (i.e. using data) research. “Citation Diversion” is the citing of papers that say something relevant to your claim, but which do not say precisely what you imply or state they say. Note that this is not lying about what the citation supports but more akin to stretching it through interpretation. “Invention” relates to the use of citations to introduce new material. Often this is an over-statement of what is contained in the cited article. So, for example, the article says, “We hypothesize that x is related to y” while the citation of that article reads, “So and so demonstrated that x is related to y”. The newer, and much stronger, claim has essentially been invented. Finally, “amplification” emerges when articles that lack primary data (e.g. review articles) are cited as authoritative sources for demonstrating that some particular thing is true. In that these articles are effectively just recycling and collating earlier work, they provide a sort of echo chamber that lends additional legitimacy to a claim without lending it additional substantive support.

I found the whole discussion interesting, but Ryan's our resident expert on science and citations, so I'll turn to him for the last word.