Wednesday 23 October 2013

Ranking University - absolute bloody nonsense.

I had to be really careful typing the title.  "Nanking University - absolute bloody nonsense." would have gotten me a visit from the Chinese Thought Police or at least the erasure of The Blob from Google-China.  I was listening on the wireless a tuthree weeks ago after one of the several-available World Rankings of Universities was published.  My alma mater TCD came top in Ireland (huzzah huzzah) and the good journalists at Newstalk asked Prof Vinny Cahill, the Dean of Research at Trinity for his opinion.  It shocked me how unwilling Cahill was to critically evaluate the value of such an accolade, preferring to bask in the arbitrary attribution of points that had put his/my University at the top of the list.  The essence of science is to be critically aware of any short-comings in your data and analysis - especially if they agree with your hypothesis.  There is a great book called How to Read a Paper by Trisha Greenhalgh.  Her advice is to start reading any paper at the Materials & Methods section.  Any serious failing there saves you from having to read the rest: no matter how persuasive the title or how significant the results.  GiGo (garbage in - garbage out) is an unforgiving god and is ignored at your peril.

On 13th October, The Sunday Times published its annual rankings of British and Irish Universities. The management of The Institute (the place where I work) promptly printed dozens of posters announcing its designation as Institute of Technology of the Year 2014 (huzzah huzzah).  That's okay, the management are not necessarily trained in Science and even if they are, their skills lie elsewhere.  Margaret Thatcher, for example, was trained as a chemist but preferred to run a country - more of a challenge.  Management can quite legitimately preen themselves a bit and retweet any positive publicity - it's their job.  There was, I am glad to say, more healthy skepticism and even bemusement amongst my scientific colleagues: how-in-heck did we get the top accolade if, by the ST's own criteria, four other ITs were better?

The criteria used by the Sunday Times were six in number, but they chose to weight Leaving Certificate points 2.5x more than the other parameters (why?  It is not explained):
  1. Median Leaving Cert Points obtained by incoming honours degree students (wt 250)
  2. Research funding (not research impact) got in 2012 / FTE staff (wt 100)
  3. % of students employed nine months after graduating (wt 100)
  4. % of high quality (1st/2.1) degrees awarded (wt 100)
  5. Student/Staff ratio (wt 100)
  6. % of students who had completed their degrees within 5 years of starting (wt 100)
Total 750 points.  Here again, TCD came top in Ireland: it may even have been the same survey which Prof Cahill was so chuffed about at the beginning of the month.  The best University in the UK is, as you ask, U Birmingham (huzzah huzzah), runner up U Leicester (one huzzah).  In the same box in the ST supplement as these gongs were announced is a list of Top by Subject from Aeronautics (Cambridge) to Tourism (Surrey) - Zoology seems to get bundled up in Biological Science so a full A-Z is not possible.  In none of these did Birmingham or Leicester feature, so I presume their top ranking is either arbitrary or subject to a well-placed envelope full of folding money

The ST acknowledges that TCD's 4% lead is being eroded as the hungry pack champ at the heels of the alpha University. Here you can see that UCD is 'better' at research than TCD:
Uni LC Res Emp 1st St/St Comp Total
TCD 215 84 93 73 60 81 606
UCD 198 93 94 62 60 78 583
Ratio 1.09 0.90 0.99 1.18 Same 1.04 1.04
If I was Prof Cahill's opposite number in UCD, I'd ask why is Leaving Cert input so over-weighted; surely, in a technological nation looking towards the future research should be given the 2.5x boost.  If you do that, then UCD edges out TCD 605 to 603 (huzzah?).  Needless to say the journalists at Newstalk and everywhere else, trained in the Arts Block, weren't interested in interviewing the Runner-Up no matter how close the gap.  Statistical insignificance is too complex a concept to deal with if the whole segment is allocated 180 seconds between the latest road deaths and the scores at the US Open.

*skeptic alert: the following analyses compare the average values of X and the average value of Y and ignore the range and error-of-estimate associated with that single tweetable metric.  Within TCD, for one example, when I was a watch-keeping non-comm on the bridge of SS Genetics, we were extremely parsimonious with handing out Firsts and used to snicker at Zoology (whose students we regarded as affable rugger-playing bohunks looking at things-bigger-than-a-breadbox through binoculars) who awarded a generous handful of these precious certificates each year.


The other criteria are in some sense uncorrelated with each other.  But if the quality of the degree means anything in these straightened times, it is that it gets you a (better) job.  Those two parameters should show some sort of relationship.  And they do . . . not.  Only with the eye of faith and by illegitimately eliminating the extraordinarily good employment record achieved by IT-The-Blanch (in the bottom right corner) is there an upward slope here.  The Correlation Coefficient (r) - a measure of association between two variables (1 = perfect positive correlation, 0 = two completely unrelated variables) = 0.11 which is, as we say, not significant.  So the proportion of 'good' degrees awarded is an institution-internal metric only hazily associated with the objective quality of the students winning them.  Let's accordingly eliminate that criterion as subjective and irrelevant.  As TCD showers out 1st Class Honours degrees like confetti, under this rule TCD (and UCD) are knocked out by UCC which had champion research results. By tricking about with the data in this way you can make any one of the top 4 or 5 Universities become Best University.


Now here's a metric that might serve to identify the colleges that do more than sit on their hands for four years while their students party. There is a wide discrepancy between average incoming Leaving Cert score but a pretty good correlation (r = 0.64) between that and % 'good' degrees awarded.  (Taking the latter with a pinch of salt as discussed in the previous paragraph). So you'd be looking for those institutions that fall above the trend line in the graph on the left.  These include Waterford and Carlow ITs and Dublin City University. These institutions appear to take kids from school at one level and spit them out four years later a little higher up the hill.

Mais revenons nous a nos data. On p.5 of the 13/Oct/13 Sunday Times Colour Supplement that reports all these findings, you can see the data from which my table and graphs are abstracted.  They claim that for DCU (ranking 4th) 186+68+94+69+64+83=583  but it doesn't.  It sums to 582.  What differ you may cry? It's only 2 parts in 1000 off.  It differs, sunshine, because if the Sunday Times can't add up a row of numbers correctly, there are likely to be other more substantive errors elsewhere in their report.  So I can (Greenhalgh rules okay) dismiss the whole thing as lazy, irresponsible, arbitrary and tendentious nonsense.

I want TCD to win and my own employer did win, but it's still nonsense. 

1 comment:

  1. Attended an interesting seminar in Tipp yesterday in which Kathleen Lynch Prof of Equality Studies in UCD gave a very similar conclusion to the process of ranking universities, but from a sociological perspective

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