Phil has had a couple of posts now about the practice of journal editors encouraging citations to a journal that they edit, and it sounds like there may be more. I should say that I don’t recall ever having an editor say something as… direct as the statement Phil quotes, and I do remember being on projects where, on our own initiative, we’ve inserted references to a journal or the work of its editor with “can’t hurt our chances!” rationale.
One might think the specific practice of editors encouraging citations to their journal for impact-factor purposes could be curbed by simply eliminating journal-level self-citations from impact factor counts. But: my suspicion is that when people insert citations in with the idea of pleasing editors at a specific journal, they mostly don’t bother to remove those citations if the paper gets rejected from the journal anyway. In other words, when journals encourage authors to cite other articles in their journal, there’s a direct and readily observed effect on impact factor as self-citations, but then there is also this hidden and downstream effect of papers that are published elsewhere. Depending on the journal’s acceptance rate and how early in the process references are added, the indirect could potentially be substantial relative to the direct effect.
On the bright–if somewhat perverse side–the practice could actually be good for anybody who wanted to try to use networks of citations across journals to make inferences about journal prestige. Because if a publication follows a chain of Journal A -> Journal B -> Journal C -> Journal D in order to get published, Journal D will have the traces of efforts to please Journals A, B, and C, including citations to those journals, whereas if it had been accepted by Journal A, it wouldn’t have traces to please B, C, and D because it was never sent there. Put another way, the order in which authors send articles would be a good way of sussing out the hierarchy of journal prestige, but that’s private information, but authors including gratuitous citations to those journals and then leaving them in is a way in which that private information can be made visible.