On Mon, 18 Sep 2006 l.hurtado_at_ED.AC.UK wrote:
> Well, I'm all for empirically-based views in these matters. So, if
> Oppenheim or others have actually soundly based studies showing what
> Stevan and Oppenheim claim, then that's to be noted. I'll have to see
> the stuff when it's published. In the meanwhile, a couple of further
> questions:
Many studies are already published. In fact many are cited in:
Harnad, S., Carr, L., Brody, T. and Oppenheim, C. (2003) Mandated
online RAE CVs Linked to University Eprint Archives. Ariadne 35.
http://eprints.ecs.soton.ac.uk/7725/
> --Pardon me for being out of touch, perhaps, but more precisely what is
> being measured? What does journal "citation counts" refer to?
The total number of citations to the articles by submitted authors (and not just those
for their 4 submitted articles!)
> Citation of journal articles? Or citation of various things in journal
> articles (and why privilege this medium?)? Or . . . what?
Citation of the articles, but that usually means citing things in the articles!
Journal articles are privileged in many disciplines because they are the
main means of reporting research. In book-based disciplines the balance
is otherwise, but the interesting thing is that even in book-based
disciplines there is a journal article citation correlation with the RAE
rankings. One would expect it to be somewhat weaker than in article-based
disciplines, but more data are needed to be exact about this.
> --What does "correlation" between RAE results and "citation counts"
> actually comprise?
The RAE ranks the departments of the c. 73 UK research universities,
with ranks from 1 to 5*. Correlation is the measure of the degree to
which values on one variable co-vary with, hence predict, values on
another variable (e.g. height is correlated with weight, the higher on
one, the higher on the other, and vice versa).
When two variables are correlated, you can predict one from the other. How
accurately you can predict is reflected by the square of the correlation
coefficient: If there is a correlation of 0.8, then the predictivity (the
percentage of the variation in one of the variables that you can already
predict from the other) is 64%. For a correlation of 0.9 it's 81% etc.
Well, as you will see in the reference list of the above-cited article,
Smith & Eysenck found a correlation of about 0.9 between the RAE ranks
and the total citation counts for the submitted researchers in Psychology.
Looking at Charles Oppenheim's studies, you will see that the correlations
varied from about 0.6 to 0.9, depending on field and year, which is all
quite high, but *especially* give that the RAE does not count citations!
The correlation is even higher with another metric, in science and
biology: prior research funding. There it can be as high as 0.99, but
that is not so good, because (1) prior funding *is* directly seen and
counted by the panel, so that high correlation could be an effect of
direct influence. Worse, using prior funding as a criterion generates a
Matthew Effect, with the already-highly-funded getting richer and richer,
and the less-funded getting poorer and poorer.
That is why a multiple regression equation is best, with many predictor
metrics, each one weighted according to the desiderata and particulars
of each discipline, and validated against further criteria, to make sure
they are measuring what we want to measure. There will be many candidate
metrics in the OA era.
> Let me lay out further reasons for some skepticism. In my own field
> (biblical studies/theology), I'd say most senior-level scholars
> actually publish very infrequently in refereed journals. We do perhaps
> more in earlier years, but as we get to senior levels we tend (a) to
> get requests for papers for multi-author volumes, and (b) we devote
> ourselves to projects that best issue in book-length publications.
That happens in other fields too, and as metric equations are calibrated
and optimised, factors like seniority will enter into the weightings
too. (Book chapter citations can and will of course be cited too --
and are, to a limited degree, already being counted by ISI and others,
because journal articles cite books and book chapters too, and those
citations are caught by ISI.)
> So if my own productivity and impact were assessed by how many journal
> articles I've published in the last five years, I'd look poor (even
> though . . . well, let's say that I rather suspect that wouldn't be the
> way I'm perceived by peers in the field).
The RAE ranks departments via individuals, and a department needs
a blend of junior and senior people, with their different style of
publication. And remember that RAE is comparing like with like. So
you might be interested in checking how your own journal article
and book chapter citation counts compare with those of your peers (or
juniors). You might be (pleasantly) surprised!
And of course in the (soon-to-hand) OA era, other metrics will be
available too, such as download counts ("hits"), which happen much
earlier, yet are correlated with later citations -- and are of course
maximized by self-archiving your papers in your institutional IR to make
them OA.
Odd new metrics will also include endogamy/exogamy scores (their preferred
polarity depending on field!), depending on the degree of self-citing,
co-author citing, co-citation circle citing, within/outside specialty
citing, intra/interdisciplinary citing, both for the citing article/author
and the cited article/author. Then there's text-proximity scores (of which
an extreme would be plagiarism), latency/longevity metrics, co-citation
to/from, CiteRank (where the weight of each citation is recursively
ranked, google style, by the degree of citedness of the citer), etc. etc.
> Or is the metric to comprise how many times I'm *cited* in journals?
It's how many times you're cited, which means how many times your articles are
cited -- in journals, but in principle also in book chapters, conferences and books.
And whether what is *being* cited is articles, chapters or books.
> If so, is there some proven correlation between a scholar's impact or
> significance of publications in the field and how many times he happens
> to be cited in this one genre of publication? I'm just a bit
> suspicious of the assumptions, which I still suspect are drawn (all
> quite innocently, but naively) from disciplines in which journal
> publication is much more the main and significant venue for scholarly
> publication.
I don't know of systematic genre comparisons (journals vs book chapters,
even empirical vs theoretical journals, reviews, etc.) but they no doubt
exist. I will branch this to the sigmetrics list where the experts are! I
am just an amateur...
> And, as we all know, "empirical" studies depend entirely on the
> assumptions that lie at their base. So their value is heavily framed
> by the validity and adequacy of the governing assumptions. No
> accusations, just concerns.
Interpretations may be influenced by assumptions, but the empirical fact
that atmospheric pressure predicts RAE ranking would be an empirical datum
(and, if it predicted it with a correlation of, say, 0.9) that would be
a reason for scrapping RAE panels for barometers theory-independently....
Stevan Harnad
> Quoting Stevan Harnad <harnad_at_ECS.SOTON.AC.UK>:
>
> > On Mon, 18 Sep 2006, Larry Hurtado wrote:
> >
> >> Stevan and I have exchanged views on the *feasibility* of a metrics
> >> approach to assessing research strength in the Humanities, and he's
> >> impressed me that something such *might well* be feasible *when/if*
> >> certain as-yet untested and undeveloped things fall into place. I note,
> >> e.g., in Stevan's addendum to Oppenheim's comment that a way of handling
> >> book-based disciplines "has not yet been looked at", and that a number
> >> of other matters are as yet "untested".
> >
> > Larry is quite right that the (rather obvious and straightforward)
> > procedure of self-archiving books' metadata and cited references in
> > order to derive a comprehensive book-citation index (which would
> > of course include journal articles citing books, books citing books,
> > and books citing journal articles) had not yet been implemented or
> > tested.
> >
> > However, the way to go about it is quite clear, and awaits only OA
> > self-archiving mandates (to which a mandate to self-archive one's book
> > metadata and reference list should be added as a matter of course).
> >
> > But please recall that I am an evangelist for OA self-archiving, because
> > I *know* it can be done, that it works, and that it confers substantial
> > benefits in terms of research access, usage and impact.
> >
> > Insofar as metrics are concerned, I am not an evangelist, but merely an
> > enthusiast: The evidence is there, almost as clearly as it is with the
> > OA impact-advantage, that citation counts are strongly correlated with
> > RAE rankings in every discipline so far tested. Larry seems to pass over
> > evidence in his remark about the as yet incomplete book citation data
> > (ISI has some, but they are only partial). But what does he have to say
> > about the correlation between RAE rankings and *journal article citation
> > counts* in the humanities (i.e., in the "book-based" disciplines)?
> > Charles will, for example, soon be reporting strong correlations in
> > Music. Even without having to wait for a book-impact index, it seems
> > clear that there are as yet no reported empirical exceptions to the
> > correlation between journal article citation metrics and RAE outcomes.
> >
> > (I hope Charles will reply directly, posting some references to his and
> > others' studies.)
> >
> >> This being the case, it is certainly not so a priori to say that a
> >> metrics approach is not now really feasible for some disciplines.
> >
> > Nothing a priori about it: A posteriori, every discipline so far tested
> > has shown positive correlations between its journal citation counts and its
> > RAE rankings, including several Humanities disciplines.
> >
> > The advantage of having one last profligate panel-based RAE in parallel
> > with the metric one in 2008 is that not a stone will be left unturned.
> > If there prove to be any disciplines having small or non-existent
> > correlations with metrics, they can and should be evaluated otherwise.
> > But let us not assume, a priori, that there will be any such
> > disciplines.
> >
> >> I emphasize that my point is not a philosophical one, but strictly
> >> whether as yet a worked out scheme for handling all Humanities
> >> disciplines rightly is in place, or capable of being mounted without
> >> some significant further developments, or even thought out adequately.
> >
> > It depends entirely on the size of the metric correlations with the
> > present RAE rankings. Some disciplines may need some supplementary forms
> > of (non-metric) evaluation if their correlations are too weak. That is an
> > empirical question. Meanwhile, the metrics will also be growing in power
> > and diversity.
> >
> >> That's not an antagonistic question, simply someone asking for the
> >> basis for the evangelistic stance of Stevan and some others.
> >
> > I evangelize for OA self-archiving of research and merely advocate
> > further development, testing and use of metrics in research performance
> > assessment, in all disciplines, until/unless evidence appears that there
> > are exceptions. So far, the objections I know of are all only in the
> > form of a priori preconceptions and habits, not objective data.
> >
> > Stevan Harnad
> >
> >> > Charles Oppenheim has authorised me to post this on his behalf:
> >> >
> >> > "Research I have done indicates that the same correlations between
> >> > RAE scores and citation counts already noted in the sciences and
> >> > social sciences apply just as strongly (sometimes more strongly)
> >> > in the humanities! But you are right, Richard, that metrics are
> >> > PERCEIVED to be inappropriate for the humanities and a lot of
> >> > educating is needed on this topic."
> >
>
>
>
> L. W. Hurtado, Professor of New Testament Language, Literature & Theology
> Director of Postgraduate Studies
> School of Divinity, New College
> University of Edinburgh
> Mound Place
> Edinburgh, UK. EH1 2LX
> Office Phone: (0)131 650 8920. FAX: (0)131 650 7952
>
Received on Tue Sep 19 2006 - 00:47:50 BST