Revision of Impact Factors

eackerma eackerma at UTKUX.UTCC.UTK.EDU
Fri Sep 15 13:39:25 EDT 2000

While I find the current discussion of ISI's Impact Factor quite interesting,
I'm afraid that I will have to take issue with the (apparently) widely
accepted notion that all self-citations should be omitted from any impact
considerations.  In particular the often unspoken, non-explicit assumption
that any self-citation is automatically suspect as being primarily for
self-aggrandisement. Self-citations seem to be automatically treated as if
they somehow taint the scholarly record with inflated citation counts.
Otherwise, why exclude them? Yet from what I have been able to find in the
published literature, no one has found any empirical evidence to support this
notion. Various rates of self-citations have been found, but little or no
empirical linkage with nefarious efforts to artificially inflate the citation
record. Much supposition and speculation, but little evidence.

What the automatic exclusion of self-citations *does* appear to do however is
to unfairly penalize researchers publishing in newer or currently
unfashionable fields, which tend to have by nature fewer researchers involved,
hence less extensive literature to draw on as a source for non-self-citations.
Also unfairly penalized are the researchers who built careers systemaically
exporing a topic and writing a series of papers that build upon each other to
form a body of relatively coherent knowledge, just as science (and other
scholarship) is supposed to do.

Therefore, until there are published studies in the literature that
empirically demonstrate the necessity for doing so, removing all
self-citations from the record before conducting a bibliometric evaluation of
research performance seems to be an unnecessary activity. It only seems to add
more work to the task of citation analysis for no good reason, while unfairly
penalizing researchers in newer, highly specialized, or currently unpopular

Eric Ackermann
School of Information Sciences
University of Tennessee-Knoxville
eackerma at

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