UK Research Evaluation Framework: Validate Metrics Against Panel Rankings

From: Stevan Harnad <>
Date: Thu, 22 Nov 2007 16:57:38 +0000

   ** Cross-Posted** Fully Hyperlinked version of this posting:

SUMMARY: Three things need to be remedied in the UK's proposed
HEFCE/RAE Research Evaluation Framework:
   (1) Ensure as broad, rich, diverse and forward-looking a battery of
candidate metrics as possible -- especially online metrics -- in all
   (2) Make sure to cross-validate them against the panel rankings in
the last parallel panel/metric RAE in 2008. The initialized weights
can then be fine-tuned and optimized by peer panels in ensuing years.
   (3) Stress that it is important -- indeed imperative -- that all
University Institutional Repositories (IRs) now get serious about
systematically archiving all their research output assets (especially
publications) so they can be counted and assessed (as well as
accessed!), along with their IR metrics (downloads, links,
growth/decay rates, harvested citation counts, etc.).
   If these three things are systematically done -- (1) comprehensive
metrics, (2) cross-validation and calibration of weightings, and (3) a
systematic distributed IR database from which to harvest them --
continuous scientometric assessment of research will be well on its
way worldwide, making research progress and impact more measurable and
creditable, while at the same time accelerating and enhancing it.
Once one sees the whole report, it turns out that the HEFCE/RAE
Research Evaluation Framework is far better, far more flexible, and
far more comprehensive than is reflected in either the press release
or the Executive Summary.

It appears that there is indeed the intention to use many more metrics
than the three named in the executive summary (citations, funding,
students), that the metrics will be weighted field by field, and that
there is considerable open-mindedness about further metrics and about
corrections and fine-tuning with time. Even for the humanities and
social sciences, where "light touch" panel review will be retained for
the time being, metrics too will be tried and tested.

This is all very good, and an excellent example for other nations,
such as Australia (also considering national research assessment with
its Research Quality Framework), the US (not very advanced yet, but no
doubt listening) and the rest of Europe (also listening, and planning
measures of its own, such as EurOpenScholar).

There is still one prominent omission, however, and it is a crucial

The UK is conducting one last parallel metrics/panel RAE in 2008. That
is the last and best chance to test and validate the candidate metrics
-- as rich and diverse a battery of them as possible -- against the
panel rankings. In all other fields of metrics -- biometrics,
psychometrics, even weather forecasting metrics ? before deployment
the metric predictors first need to be tested and shown to be valid,
which means showing that they do indeed predict what they were
intended to predict. That means they must correlate with a "criterion"
metric that has already been validated, or that has "face-validity" of
some kind.

The RAE has been using the panel rankings for two decades now (at a
great cost in wasted time and effort to the entire UK research
community -- time and effort that could instead have been used to
conduct the research that the RAE was evaluating: this is what the
metric RAE is primarily intended to remedy).

But if the panel rankings have been unquestioningly relied upon for 2
decades already, then they are a natural criterion against which the
new battery of metrics can be validated, initializing the weights of
each metric within a joint battery, as a function of what percentage
of the variation in the panel rankings each metric can predict.

This is called "multiple regression" analysis: N "predictors" are
jointly correlated with one (or more) "criterion" (in this case the
panel rankings, but other validated or face-valid criteria could also
be added, if there were any). The result is a set of "beta" weights on
each of the metrics, reflecting their individual predictive power, in
predicting the criterion (panel rankings). The weights will of course
differ from discipline by discipline.

Now these beta weights can be taken as an initialization of the metric
battery. With time, "super-light" panel oversight can be used to
fine-tune and optimize those weightings (and new metrics can always be
added too), to correct errors and anomalies and make them reflect the
values of each discipline.

(The weights can also be systematically varied to use the metrics to
re-rank in terms of different blends of criteria that might be
relevant for different decisions: RAE top-sliced funding is one sort
of decision, but one might sometimes want to rank in terms of
contributions to education, to industry, to internationality, to
interdisciplinarity. Metrics can be calibrated continuously and can
generate different "views" depending on what is being evaluated. But,
unlike the much abused "university league table," which ranks on one
metric at a time (and often a subjective opinion-based rather than an
objective one), the RAE metrics could generate different views simply
by changing the weights on some selected metrics, while retaining the
other metrics as the baseline context and frame of reference.)

To accomplish all that, however, the metric battery needs to be rich
and diverse, and the weight of each metric in the battery has to be
initialised in a joint multiple regression on the panel rankings. It
is very much to be hoped that HEFCE will commission this all-important
validation exercise on the invaluable and unprecedented database they
will have with the unique, one-time parallel panel/ranking RAE in

That is the main point. There are also some less central points:

The report says -- a priori -- that REF will not consider journal
impact factors (average citations per journal), nor author impact
(average citations per author): only average citations per paper, per
department. This is a mistake. In a metric battery, these other
metrics can be included, to test whether they make any independent
contribution to the predictivity of the battery. The same applies to
author publication counts, number of publishing years, number of
co-authors -- even to impact before the evaluation period. (Possibly
included vs. non-included staff research output could be treated in a
similar way, with number and proportion of staff included also being

The large battery of jointly validated and weighted metrics will make
it possible to correct the potential bias from relying too heavily on
prior funding, even if it is highly correlated with the panel
rankings, in order to avoid a self-fulfilling prophecy which would
simply collapse the Dual RAE/RCUK funding system into just a
multiplier on prior RCUK funding.

Self-citations should not be simply excluded: they should be included
independently in the metric battery, for validation. So should
measures of the size of the citation circle (endogamy) and degree of

Nor should the metric battery omit the newest and some of the most
important metrics of all, the online, web-based ones: downloads of
papers, links, growth rates, decay rates, hub/authority scores. All of
these will be provided by the UK's growing network of UK Institutional
Repositories. These will be the record-keepers -- for both the papers
and their usage metrics -- and the access-providers, thereby
maximizing their usage metrics.

REF should put much, much more emphasis on ensuring that the UK
network of Institutional Repositories systematically and
comprehensively records its research output and its metric performance

But overall, thumbs up for a promising initiative that is likely to
serve as a useful model for the rest of the research world in the
online era.


Harnad, S., Carr, L., Brody, T. & Oppenheim, C. (2003) Mandated online
RAE CVs Linked to University Eprint Archives: Improving the UK Research
Assessment Exercise whilst making it cheaper and easier. Ariadne 35.

Brody, T., Kampa, S., Harnad, S., Carr, L. and Hitchcock, S. (2003)
Digitometric Services for Open Archives Environments. In Proceedings of
European Conference on Digital Libraries 2003, pp. 207-220, Trondheim,

Harnad, S. (2006) Online, Continuous, Metrics-Based Research Assessment.
Technical Report, ECS, University of Southampton.

Harnad, S. (2007) Open Access Scientometrics and the UK Research
Assessment Exercise. In Proceedings of 11th Annual Meeting of the
International Society for Scientometrics and Informetrics 11(1), pp.
27-33, Madrid, Spain. Torres-Salinas, D. and Moed, H. F., Eds.

Brody, T., Carr, L., Harnad, S. and Swan, A. (2007) Time to Convert to
Metrics. Research Fortnight pp. 17-18.

Brody, T., Carr, L., Gingras, Y., Hajjem, C., Harnad, S. and
Swan, A. (2007) Incentivizing the Open Access Research Web:
Publication-Archiving, Data-Archiving and Scientometrics. CTWatch
Quarterly 3(3).

   Fully Hyperlinked version of this posting:

Stevan Harnad

If you have adopted or plan to adopt a policy of providing Open Access
to your own research article output, please describe your policy at:

    BOAI-1 ("Green"): Publish your article in a suitable toll-access journal
    BOAI-2 ("Gold"): Publish your article in an open-access journal if/when
    a suitable one exists.
    in BOTH cases self-archive a supplementary version of your article
    in your own institutional repository.
Received on Thu Nov 22 2007 - 17:28:15 GMT

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