October | 2009 | In the Dark

Archive for October, 2009

I could not sleep for thinking of the sky

Posted in Poetry with tags astronomy, John Masefield on October 21, 2009 by telescoper

A comment from another blogger about an item of mine containing another bit of poetry led me to put up this astronomy-inspired poem, by the former Poet Laureate John Masefield. It’s from a cycle called Lollingdown Downs, and is actually the 12th poem in the sequence. I hope you like it.

I could not sleep for thinking of the sky,
The unending sky, with all its million suns
Which turn their planets everlastingly
In nothing, where the fire-haired comet runs.

If I could sail that nothing, I should cross
Silence and emptiness with dark stars passing,
Then, in the darkness, see a point of gloss
Burn to a glow, and glare, and keep amassing,

And rage into a sun with wandering planets
And drop behind, and then, as I proceed,
See his last light upon his last moon’s granites
Die to a dark that would be night indeed.

Night where my soul might sail a million years
In nothing, not even death, not even tears.

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It’s a PhD Jim, but not as we know it…

Posted in Uncategorized with tags Mark Brake, University of Glamorgan on October 19, 2009 by telescoper

A story in today’s WalesOnline, originally published in the Western Mail, inspired me to add a short item to this blog.

Mark Brake is a writer and broadcaster and Professor of Science Communication at the University of Glamorgan. According to the Western Mail, in May 2006 he completed a detailed tender for the Swindon-based RCPO – a professional procurement unit that works with seven of Britain’s research councils. Allegedly, in the 26-page document, Professor Brake claimed to hold a doctorate with the title Astrophysics: Chemical Evolution of the Galaxies, awarded by University College Cardiff, the name held by Cardiff University until 1988. He never wrote such a thesis and holds no such degree.

The article goes on to say that the application was successful, and the University of Glamorgan was awarded £285,264 for a six-month Researchers in Residence project. Surprisingly, although the University of Glamorgan has not disputed the facts in the article, it has failed to return the money.

You will find no mention of this episode on Professor Brake’s Wikipedia page, the content of which appears nevertheless to be hotly disputed.

Professor Brake, a self-styled “astrobiologist”, declined to comment on the article, but a comment on the WalesOnline site says it all:

It’s a PhD Jim……..but not as we know it………..

POSTSCRIPT 20th October 2009

The WalesOnline story has now been amended to state that the application was not successful. I am therefore happy to retract my criticism of the University of Glamorgan for failing to return the money, and accept that they never received it.

The rest of the story remains in place.

Moreover, here is the relevant part of page 19 of the 26-page document that was submitted to the RCPO. Apologies for the slightly wonky result of the scanning. It’s not ambiguous, and I have no reason to believe that it is a forgery. Had Mark Brake been awarded a PhD then a copy of the thesis would be in the Cardiff University library (which it isn’t) and the National Library of Wales (which it isn’t). Either this document is a forgery or Professor Brake did indeed falsely represent his qualifications in the application. brake

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Ergodic Means…

Posted in The Universe and Stuff with tags anthropic principle, Cosmology, ergodic hypothesis, multiverse, Physics, probability, statistical physics on October 19, 2009 by telescoper

The topic of this post is something I’ve been wondering about for quite a while. This afternoon I had half an hour spare after a quick lunch so I thought I’d look it up and see what I could find.

The word ergodic is one you will come across very frequently in the literature of statistical physics, and in cosmology it also appears in discussions of the analysis of the large-scale structure of the Universe. I’ve long been puzzled as to where it comes from and what it actually means. Turning to the excellent Oxford English Dictionary Online, I found the answer to the first of these questions. Well, sort of. Under etymology we have

ad. G. ergoden (L. Boltzmann 1887, in Jrnl. f. d. reine und angewandte Math. C. 208), f. Gr.

I say “sort of” because it does attribute the origin of the word to Ludwig Boltzmann, but the greek roots (εργον and οδοσ) appear to suggest it means “workway” or something like that. I don’t think I follow an ergodic path on my way to work so it remains a little mysterious.

The actual definitions of ergodic given by the OED are

Of a trajectory in a confined portion of space: having the property that in the limit all points of the space will be included in the trajectory with equal frequency. Of a stochastic process: having the property that the probability of any state can be estimated from a single sufficiently extensive realization, independently of initial conditions; statistically stationary.

As I had expected, it has two meanings which are related, but which apply in different contexts. The first is to do with paths or orbits, although in physics this is usually taken to meantrajectories in phase space (including both positions and velocities) rather than just three-dimensional position space. However, I don’t think the OED has got it right in saying that the system visits all positions with equal frequency. I think an ergodic path is one that must visit all positions within a given volume of phase space rather than being confined to a lower-dimensional piece of that space. For example, the path of a planet under the inverse-square law of gravity around the Sun is confined to a one-dimensional ellipse. If the force law is modified by external perturbations then the path need not be as regular as this, in extreme cases wandering around in such a way that it never joins back on itself but eventually visits all accessible locations. As far as my understanding goes, however, it doesn’t have to visit them all with equal frequency. The ergodic property of orbits is intimately associated with the presence of chaotic dynamical behaviour.

The other definition relates to stochastic processes, i.e processes involving some sort of random component. These could either consist of a discrete collection of random variables {X₁…X_n} (which may or may not be correlated with each other) or a continuously fluctuating function of some parameter such as time t, i.e. X(t) or spatial position (or perhaps both).

Stochastic processes are quite complicated measure-valued mathematical entities because they are specified by probability distributions. What the ergodic hypothesis means in the second sense is that measurements extracted from a single realization of such a process have a definition relationship to analagous quantities defined by the probability distribution.

I always think of a stochastic process being like a kind of algorithm (whose workings we don’t know). Put it on a computer, press “go” and it spits out a sequence of numbers. The ergodic hypothesis means that by examining a sufficiently long run of the output we could learn something about the properties of the algorithm.

An alternative way of thinking about this for those of you of a frequentist disposition is that the probability average is taken over some sort of statistical ensemble of possible realizations produced by the algorithm, and this must match the appropriate long-term average taken over one realization.

This is actually quite a deep concept and it can apply (or not) in various degrees. A simple example is to do with properties of the mean value. Given a single run of the program over some long time T we can compute the sample average

$\bar{X}_T\equiv \frac{1}{T} \int_0^Tx(t) dt$

the probability average is defined differently over the probability distribution, which we can call p(x)

$\langle X \rangle \equiv \int x p(x) dx$

If these two are equal for sufficiently long runs, i.e. as T goes to infinity, then the process is said to be ergodic in the mean. A process could, however, be ergodic in the mean but not ergodic with respect to some other property of the distribution, such as the variance. Strict ergodicity would require that the entire frequency distribution defined from a long run should match the probability distribution to some accuracy.

Now we have a problem with the OED again. According to the defining quotation given above, ergodic can be taken to mean statistically stationary. Actually that’s not true. ..

In the one-parameter case, “statistically stationary” means that the probability distribution controlling the process is independent of time, i.e. that p(x,t)=p(x,t+Δt) . It’s fairly straightforward to see that the ergodic property requires that a process X(t) be stationary, but the converse is not the case. Not every stationary process is necessarily ergodic. Ned Wright gives an example here. For a higher-dimensional process, such as a spatially-fluctuating random field the analogous property is statistical homogeneity, rather than stationarity, but otherwise everything carries over.

Ergodic theorems are very tricky to prove in general, but there are well-known results that rigorously establish the ergodic properties of Gaussian processes (which is another reason why theorists like myself like them so much). However, it should be mentioned that even if the ergodic assumption applies its usefulness depends critically on the rate of convergence. In the time-dependent example I gave above, it’s no good if the averaging period required is much longer than the age of the Universe; in that case even ergodicity makes it difficult to make inferences from your sample. Likewise the ergodic hypothesis doesn’t help you analyse your galaxy redshift survey if the averaging scale needed is larger than the depth of the sample.

Moreover, it seems to me that many physicists resort to ergodicity when there isn’t any compelling mathematical grounds reason to think that it is true. In some versions of the multiverse scenario, it is hypothesized that the fundamental constants of nature describing our low-energy turn out “randomly” to take on different values in different domains owing to some sort of spontaneous symmetry breaking perhaps associated a phase transition generating cosmic inflation. We happen to live in a patch within this structure where the constants are such as to make human life possible. There’s no need to assert that the laws of physics have been designed to make us possible if this is the case, as most of the multiverse doesn’t have the fine tuning that appears to be required to allow our existence.

As an application of the Weak Anthropic Principle, I have no objection to this argument. However, behind this idea lies the assertion that all possible vacuum configurations (and all related physical constants) do arise ergodically. I’ve never seen anything resembling a proof that this is the case. Moreover, there are many examples of physical phase transitions for which the ergodic hypothesis is known not to apply. If there is a rigorous proof that this works out, I’d love to hear about it. In the meantime, I remain sceptical.

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Au Privave

Posted in Jazz with tags Au Privave, Charlie Parker, Oscar Peterson, Sonny Stitt on October 18, 2009 by telescoper

At the risk of becoming a complete bore on the subject of bebop I thought I’d follow up an earlier post on the joys of jazz with this brilliant performance of yet another Charlie Parker tune, not by the man himself, but by one of his disciples.

I was lucky enough to hear Sonny Stitt live a number of times and he was always brilliant; he died in 1982. He was criticised by some jazz buffs between numbers during one gig I was at with the words “You’re just playing like Charlie Parker!”, to which he replied by handing his alto saxophone to the twit in the audience and saying “Here then. YOU play like Charlie Parker.”

Anyway, in the late 1950s (after Charlie Parker had died) Sonny Stitt sat in as on alto saxophone with the Oscar Peterson trio of which Ray Brown (bass) and Ed Thigpen (drums) were the other two members. They made a classic album for the Verve label which features a number of Charlie Parker numbers. Oscar Peterson isn’t my absolute favourite jazz pianist but it has to be said that he and his sidemen build up a colossal head of steam on these records, especially the one I’ve picked which is called Au Privave.

I tried for ages to unravel this intricate little tune. It’s basically a twelve-bar blues, but it is built on much more complicated chords than the usual blues cycle. In its simplest form, the blues involves only three chords, the same three that most rock-and-roll tunes are built on. The foundation is a “tonic” chord (T) based on the root note of whatever key it’s played in, often a basic triad consisting of the first, third and five notes of a major scale starting on that note or including the dominant 7th. The next chord is the subdominant chord (S), shifting things up by a perfect fourth relative to the tonic, and then finally we have the dominant (D) which brings us up by a fifth from the original root note.

The basic twelve-bar blues has one chord per bar. The first four bars are accompanied by the tonic, then the subdominant S takes over for two bars followed by a return to the tonic for another two. The last four bars introduce the dominant (but only for one bar), followed by S for one and then back down to the root for the final two.

In a standard blues in F the sequence would thus be

| F| F| F |F | B♭| B♭| F| F | C| B♭| F| F|,

or possibly with F7 etc. The slow and relatively simple progression of chords gives these blues a rather statuesque form: the soloist has to be really good to keep the thing going without getting bogged down. When played by a master even the simplest blues can be immensely powerful, but they can also be very dull when played not so well. It may be simple, but it certainly isn’t easy.

Au Privave is in F but has considerably more complicated changes than the bog-standard F blues. Parker inserted several intermediate chords to keep the harmonies moving and dispensed with some of the conventional progressions. There are also more chords, usually two per bar rather than just one. The sequence here looks more like

| F| Gm7C7| F |Cm7F7| B♭| B♭| F7Gm7| Am7D7 | Gm7| C| FD7| G7C7|,

although I’m not sure I got them right as it tends to be played very fast! It’s a lot more to remember, but it’s also a much more dynamic setting to improvise in which is what people like Charlie Parker wanted to create. Instead of moving quasi-statically through perfect intervals each chorus, you run helter-skelter through a constantly shifting harmonic environment. Notice also that there’s no comfortable return to the tonic at measure 12, even. The appearance of a C7 chord here is called a turnaround. Complicated? Yes, I suppose it is. But whenever I hear it played by Sonny Stitt it’s always just four minutes of sheer exhilaration.

Oh, and there’s another thing. Listen to the chorus that starts about 2:58. Did he really play all twelve bars without breathing?

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The Mailstorm

Posted in Uncategorized with tags Jan Moir, Stephen Gately, The Daily Mail, Twitter on October 17, 2009 by telescoper

Yesterday The Daily Mail – loathsome ragbag of hate-mongering lies masquerading as a newspaper – ran a piece by columnist Jan Moir on their website that sank below the level of the gutter and into the deepest depths of sheer evil.

The piece was about Stephen Gately, a singer and former member of the group Boyzone, who died suddenly over a week ago at the age of 33. Although the coroner declared his death to be of natural causes, the circumstances surrounding his death do remain a little unclear. However, anyone with any degree of sensitivity would have treated the matter as a private one and refrained from intruding in order allow his friends, family, and, especially, his partner to come to terms with what had happened. Anyone with any degree of sensitivity, that is. Not Jan Moir.

You see, Stephen Gately was gay. That’s no big deal for many people these days, but for the Daily Mail it made him a target for a post-mortem hatchet job. No need to worry about the laws of defamation as you can’t libel the dead. No need to check the facts, just sit down and let the vitriol pour out. Right up Jan Moir’s street.

This poisonous excuse for a human being composed a piece with the title. Why there was nothing `natural’ about Stephen Gately’s death. This wasn’t journalism of course. Jan Moir hadn’t uncovered any new facts about the case. Nothing she wrote was backed up by any evidence. It was simply an exercise of blind bigotry, achieved through insinuation and deliberately designed to pander to the prejudices of the Daily Mail’s readership.

For example

… fit 33-year-old men do not just climb into their pyjamas and go to sleep on the sofa, never to wake up again

Well I’m sorry, Jan, but they do. Fit young people drop dead while walking along the street too. A number of medical conditions can lead sudden unexpected death in apparently healthy people.

Here’s another example, in which the monstrous Moir expands the horizons of her rant to encompass racism

After a night of clubbing, Cowles and Gately took a young Bulgarian man back to their apartment.

Bulgarian? Must be dodgy. Must have been a kinky threesome. Shows that the civil partnership of Gately and his partner Andrew Cowles was meaningless. All gay men are at it like rabbits all the time. They’re all irretrievably sleazy. We all know that. We read about it in the Daily Mail.

As a matter of fact, the third man was Georgi Dochev (yes, Bulgarians have names too) , an old friend of the couple. It seems quite a reasonable alternative hypothesis that the three of them came home after a night out and simply crashed out wherever they could. I don’t know whether that was the case or not. Neither does Jan Moir, but she obviously didn’t want the absence of relevant facts to get in the way of a story.

Another real sadness about Gately’s death is that it strikes another blow to the happy-ever-after myth of civil partnerships. Gay activists are always calling for tolerance and understanding about same-sex relationships, arguing that they are just the same as heterosexual marriages.

Sheesh. I won’t go on unpicking this odious item otherwise I’ll get angry again. I hope I’ve made the point. In any case Charlie Brooker in the Guardian has already done a much better job than I could.

Anyway, as soon as I found out about this piece (via Facebook) I fired off a complaint to the Press Complaints Commission as it was clearly in violation of Sections 1, 5 and 12 of their Code of Practice. Meanwhile a storm brewed up on Twitter (of which I am not a member) and so many people filed complaints to the PCC that their website crashed. The Daily Mail’s own readership – not known for their liberal attitudes – roundly condemned the piece through the comments facility. Finally, and perhaps most importantly from the point of view of having an impact on the Mail itself, several advertisers (including Marks & Spencer and Nestlé) pulled their adverts off the website because they wanted to disassociate themselves from the opinions expressed there. The loss of advertising revenue probably means a lot more to bosses at the Daily Mail than any appeal to decency or respect.

The piece is still there, but has been heavily edited and has a new title. It’s still offensive, though. I’ll be following subsequent events with interest and have already made plans to burn Jan Moir in effigy at the forthcoming bonfire night celebrations on November 5th. I hope the Daily Mail shows her the door too.

Looking back on this affair a day later, I have to say that in a way I’m actually glad Jan Moir wrote the piece. Thoroughly disgusted as I am by what she wrote I feel bound to defend her right to say what she thinks. Gagging such people is not the answer. That piece tells us exactly the kind of creature she is. She can’t squirm out of this by offering a half-baked apology and saying it was just a joke. The Daily Mail published, and Jan Moir is damned. May she rot in hell.

Another thing this episode demonstrates the immense power of Twitter to do real good. I had previously thought of it as a trivial bit of net gimmickry. Now I’m seriously thinking of joining Twitter in the hope of adding one more voice to the campaign to save pure science from the oblivion it seems to be headed for.

The problem is that Twitter works through messages limited to 140 characters in length. Since I can’t seem to write a blog post in less than a thousand words I don’t think my tweets will be very effective..

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Classic Collection

Posted in Biographical, Music with tags Banarama, Dee-Lite, S'Express on October 16, 2009 by telescoper

I’ve been told on more than one occasion that some people find all the stuff about opera and poetry and the like is a bit too highbrow for them. In an effort to make myself more commercially relevant I’ve therefore decided to include something a bit different from my usual line of music posts.

Twenty years ago, while I was still living in Brighton, I didn’t go to the Opera or to classical music concerts at all, but instead went out most nights to various nightclubs (most of which have now closed down). This was all before I became too old and decrepid to be anything but an embarrassment in such a context. I also had a habit of buying singles of the records I heard night after night in the clubs which I would play before going out to get me into the mood for a boogie. I like dancing, in case you hadn’t guessed.

In recently sorted through my old vinyl record collection and hunted through Youtube to find the corresponding videos. So here are three examples from my own classic collection which will hopefully prevent any further accusations that this blog is too erudite. It won’t do much for my street cred with the younger generation, though, as these records are all older than most students.

First one up is from the cheesy end of the spectrum. It’s the sublime Bananarama, doing a very camp cover version of the Supremes’ hit Nathan Jones. I want you to pay particularly close attention to the video as I expect you all to learn the moves. There’ll be a test. Right hand on right hip. Left arm extended. Ready? Go!

Number two in my hit parade belongs to the commercial wing of the Acid House movement that swept through dance clubs during the late 1980s. S’Express released Hey Music Lover in 1989 and it immediately became one of my favourite things to dance to. It’s nowhere near as effective watching it on a small screen, away from the thumping sounds and whirling psychedelic environment of a nightclub, but this one always used to make the blood rush to my head and it also seemed to get the best out of the best dancers. Note the sly references to Federico Fellini in the video.

Lastly but definitely not leastly is easily the best dance record of the classical period under consideration. It deserves to be in the collection because it still packs the dance floors twenty years on. Fabulously funky, tantalising trippy and devilishly danceable, this was a huge hit in 1990 for the fantastic Dee-Lite – here is a medley of their hit Groove is in the Heart.

And that’s enough of that.

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Greatness in Little

Posted in Poetry, The Universe and Stuff with tags Cosmology, Lord Martin Rees, Richard Leigh on October 15, 2009 by telescoper

The BBC Website yesterday mentioned that according to the British Astronomer Royal, Lord Martin Rees, celestial bodies are less complicated than the bodies of insects – let alone those of human beings – and cosmology is an easier science than the study of a balanced diet.

As I was tucking into my carefully balanced meal of fish and chips last night, the first part of the quotation suddenly reminded me of the following poem Greatness in Little by Richard Leigh (1649-1728), a relatively obscure poet of the seventeenth century who managed to excel himself in this particular poem of 1675 in which he compares the intricate workings of insects with the grandest achievements of human explorers.

In spotted globes, that have resembled all
Which we or beasts possess to one great ball
Dim little specks for thronging cities stand,
Lines wind for rivers, blots bound sea and land.
Small are those spots which in the moon we view,
Yet glasses these like shades of mountains shew;
As what an even brightness does retain,
A glorious level seems, and shining plain.
Those crowds of stars in the populous sky,
Which art beholds as twinkling worlds on high,
Appear to naked, unassisted sight
No more than sparks or slender points of light.
The sun, a flaming universe alone,
Bigger than that about which his fires run;
Enlightening ours, his globe but part does gild,
Part by his lustre or Earth’s shades concealed;
His glory dwindled so, as what we spy
Scarce fills the narrow circle of the eye.
What new Americas of light have been
Yet undiscovered there, or yet unseen,
Art’s near approaches awfully forbid,
As in the majesty of nature hid.
Nature, who with like state, and equal pride,
Her great works does in height and distance hide,
And shuts up her minuter bodies all
In curious frames, imperceptibly small.
Thus still incognito, she seeks recess
In greatness half-seen, or dim littleness.
Ah, happy littleness! that art thus blest,
That greatest glories aspire to seem least.
Even those installed in a higher sphere,
The higher they are raised, the less appear,
And in their exaltation emulate
Thy humble grandeur and thy modest state.
Nor is this all thy praise, though not the least,
That greatness is thy counterfeit at best.
Those swelling honours, which in that we prize,
Thou dost contain in thy more thrifty size;
And hast that pomp, magnificence does boast,
Though in thy stature and dimensions lost.
Those rugged little bodies whose parts rise
And fall in various inequalities,
Hills in the risings of their surface show,
As valleys in their hollow pits below.
Pompous these lesser things, but yet less rude
Than uncompact and looser magnitude.
What Skill is in the frame of Insects shown?
How fine the Threds, in their small Textures spun?
How close those Instruments and Engines knit,
Which Motion, and their slender Sense transmit?
Like living Watches, each of these conceals
A thousand Springs of Life, and moving wheels.
Each ligature a Lab’rynth seems, each part
All wonder is, all Workmanship and Art.
Rather let me this little Greatness know,
Then all the Mighty Acts of Great Ones do.
These Engines understand, rather than prove
An Archimedes, and the Earth remove.
These Atom-Worlds found out, I would despise
Colombus, and his vast Discoveries.

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I Did Expect the Spanish Inquisition…

Posted in Biographical, Science Politics with tags astronomy, grant applications, STFC, Swindon on October 14, 2009 by telescoper

So that was it. D-Day.

Our application to the Science and Technology Facilities Council (STFC) for a rolling grant to cover the next 5 years of astronomy research went in a few months ago. Over the summer we got feedback from independent referees. But today was the crunch. The dreaded panel visit.

In the old days the grants panel used to visit the applicants at their own institute, chat to the postdocs and staff, help themselves to free food, and generally get a feel for the place over a period of a couple of days. Now, all that cosiness has gone. Nowadays the applicants visit the panel. Mohammed and the Mountain and all that (except I’m not sure which is which).

A large group of astronomers are involved in this application, but STFC rules permit only three representatives to make the pilgrimage to Swindon in order to testify in front of the experts. I was among the chosen few, although I was not particularly grateful for this honour.

This would have been stressful enough, but there is grim talk of slashed budgets and looming financial disaster for UK astronomy. The successful launch of Planck and Herschel in May, followed by the exceptionally promising snippets of data that we’ve been getting, has strengthened what was already a very strong case. These events should have given us all the cards. The trouble is, it looks like the casino has gone bust.

We were all a bit nervous, I can tell you, as we travelled to Swindon on the early train from Cardiff. Steve Eales is Principal Investigator on the grant and he’s a self-confessed morning person so he went on a ludicrously early train in case something happened to delay him. Derek Ward-Thompson and I followed on a more sensible one, but we all got there safely and on time in the end.

We started with a presentation by Steve which he delivered in superb style, keeping exactly to time but also ticking all the boxes we were asked to cover in the instructions we got. The science updates from the last 6 months are really impressive, and it was all made even more dramatic when he told the panel that the new Herschel images they were seeing were not public and therefore that they shouldn’t look at them.

Then we were due for 45 minutes questioning by the panel. I thought it might be something like Blind Date because there were three of us to do the answering. Question Number One for Contestant Number Two, that sort of thing, except that we anticipated slightly more technical questions and we weren’t expecting Cilla Black to be there.

But there weren’t many questions at all. In fact, I had only one question (on the cosmology part). It was curiously anti-climactic after having had a near-sleepless night worrying about it. This could mean either that they’d already decided to close us down, that they’d already decided we were brilliant, or that they already knew there was no money so there wasn’t any point in asking anything.

So 25 minutes into the 45 allotted we were shown the door and headed back to Cardiff by train. It was like Monty Python in reverse: we did expect the Spanish Inquisition, but it never happened…

We jabbered nervously on the return journey because the adrenalin was still going, speculating about what it all meant but not coming to any real conclusions except that Steve had given a great presentation and that we had all answered the questions as well as we could have been expected to. It’s all out of our hands now.

The trouble is that we’re not likely to get a new grant announcement until April 2010, which is actually when the grant is supposed to start. The postdoctoral researchers we currently employ will have to wait until then to hear about possible extensions to their contracts. Perhaps by April the management will have sorted out the current STFC crisis so we can get on and do some science with the wonderful new data.

On the other hand, perhaps not….

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The League of Extraordinary Gibberish

Posted in Bad Statistics with tags Cardiff University, League Tables, Times Higher, World University Rankings on October 13, 2009 by telescoper

After a very busy few days I thought I’d relax yesterday by catching up with a bit of reading. In last week’s Times Higher I found there was a supplement giving this year’s World University Rankings.

I don’t really approve of league tables but somehow can’t resist looking in them to see where my current employer Cardiff University lies. There we are at number 135 in the list of the top 200 Universities. That’s actually not bad for an institute that’s struggling with a Welsh funding system that seriously disadvantages it compared to our English colleagues. We’re a long way down compared to Cambridge (2nd), UCL (4th), Imperial and Oxford (5th=) . Compared to places I’ve worked at previously we’re significantly below Nottingham (91st) but still above Queen Mary (164) and Sussex (166). Number 1 in the world is Harvard, which is apparently somewhere near Boston (the American one).

Relieved that we’re in the top 200 at all, I decided to have a look at how the tables were drawn up. I wish I hadn’t bothered because I was horrified at the methodological garbage that lies behind it. You can find a full account of the travesty here. In essence, however, the ranking is arrived at by adding six distinct indicators, weighted differently but with weights assigned for no obvious reason, each of which is arrived at by dubious means and which is highly unlikely to mean what it purports. Each indicator is magically turned into a score out of 100 before being added to all the other ones (with appropriate weighting factors).

The indicators are:

Academic Peer Review. This is weighted 40% of the overall score for each institution and is obtained by asking a sample of academics (selected in a way that is not explained). This year 9386 people were involved; they were asked to name institutions they regard as the best in their field. This sample is a tiny fraction of the global academic population and it would amaze me if it were representative of anything at all!
Employer Survey. The pollsters asked 3281 graduate employers for their opinions of the different universities. This was weighted 10%.
Staff-Student Ratio. Counting 20%, this is supposed to be a measure of “teaching quality”! Good teaching = large numbers of staff? Not if most of them don’t teach as at many research universities. A large staff-student ratio could even mean the place is really unpopular!
International Faculty. This measures the proportion of overseas staff on the books. Apparently a large number of foreign lecturers makes for a good university and “how attractive an institution is around the world”. Or perhaps that it finds it difficult to recruit its own nationals. This one counts only 5%.
International Students. Another 5% goes to the fraction of each of the student body that is from overseas.
Research Excellence. This is measured solely on the basis of citations – I’ve discussed some of the issues with that before – and counts 20%. They choose to use an unreliable database called SCOPUS, run by the profiteering academic publisher Elsevier. The total number of citations is divided by the number of faculty to “give a sense of the density of research excellence” at the institution.

Well I hope by now you’ve got a sense of the density of the idiots who compiled this farrago. Even if you set aside the issue of the accuracy of the input data, there is still the issue of how on Earth anyone could have thought it was sensible to pick such silly ways of measuring what makes a good university, assigning random weights to them, and then claiming that they had achieved something useful. They probably got paid a lot for doing it too. Talk about money for old rope. I’m in the wrong business.

What gives the game away entirely is the enormous variance from indicator to another. This means that changing the weights slightly would produce a drastically different list. And who is to say that the variables should be added linearly anyway? Is a score of 100 really worth precisely twice as much as a score of 50? What do the distributions look like? How significant are the differences in score from one institute to another? And what are we actually trying to measure anyway?

Here’s an example. The University of California at Berkeley scores 100/100 for 1,2 and 4 and 86 for 5. However for Staff/Student ratio (3) it gets a lowly 25/100 and for (6) it gets only 34, which combine take it down to 39th in the table. Exclude this curiously-chosen proxy for teaching quality and Berkeley would rocket up the table.

Of course you can laugh these things off as unimportant trivia to be looked at with mild amusement over a glass of wine, but such things have increasingly found their way into the minds of managers and politicians. The fact that they are based on flawed assumptions, use a daft methodology, and produce utterly meaningless results seems to be irrelevant. Because they are based on numbers they must represent some kind of absolute truth.

There’s nothing at all wrong with collating and publishing information about schools and universities. Such facts should be available to the public. What is wrong is the manic obsession with condensing disparate sets of conflicting data into a single number just so things can be ordered in lists that politicians can understand.

You can see the same thing going on in the national newspapers’ lists of University rankings. Each one uses a different weighting and different data and the lists are drastically different. They give different answers because nobody has even bothered to think about what the question is.

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Lux Aeterna

Posted in Music with tags 2001: A Space Odyssey, George Ligeti, Lux Aeterna on October 12, 2009 by telescoper

Since my recent trip to see György Ligeti‘s extraordinary Opera Le Grande Macabre, I’ve been trying to find out a bit more about the composer. I’ve stumbled across a few of his works, including some very strange and difficult piano pieces which I might put up here sometime. However, I thought it would be nice to acknowledge probably his most famous work particularly because it came up in a previous post.

Lux Aeterna is a choral work for sixteen unaccompanied voices which was written in 1966. Along with excerpts from his Requiem (from the Kyrie and Dies Irae) and the orchestral piece Atmospheres (1961), this composition formed part of the soundtrack for Stanley Kubrick’s 2001: A Space Odyssey. What I didn’t know until reading about Lux Aeterna was that Kubrick didn’t bother to ask for permission to use Ligeti’s work in his film and it was only after heated discussions that he agreed to pay the composer a fee. Ligeti doesn’t seem to have minded that much, however, as he subsequently went on record saying that he admired Kubrick’s work enormously.

Lux Aeterna (“Eternal Light”) can be thought of as a kind of postscript to the Requiem and its text comes from the Roman Catholic Mass for the Dead (in Latin):

Lux aeterna luceat eis, Domine, cum sanctis tuis in aeternum, quia pius es. Requiem aeternum dona eis, Domine; et lux perpetua luceat eis.

Although the piece is officially dated later than Ligeti’s setting of the rest of the Requiem Mass, the compositional technique he used seems to be similar and its emotional feel seems also to belong with that longer work. It’s an uncompromisingly avant-garde work, exploiting a dense atonal polyphony to create a strange atmosphere that seems to combine agonised apprehension with a kind of bewildered exhilaration.

Here it is combined with images from the film and various bits of interesting information about Ligeti’s life and music.

I can only speak directly for myself, of course, but I suspect many will agree with me that it’s a remarkably effective piece on its own that has even greater impact in the context of the movie. However, I wonder how many would say that it is beautiful? I know I would.