Archive for January, 2012

Academic Interactions

Posted in The Universe and Stuff with tags , on January 31, 2012 by telescoper

I’ve spent nearly all day getting my notes ready to start teaching Accidental Raunchy Slippers  Nuclear and Particle Physics tomorrow to the massed ranks of Third-Year Physics students here in the School of Physics & Astronomy at Cardiff University. I’ve drawn so many Feynman diagrams in the last couple of days that I’ve started to see them everywhere I look, even in entirely unexpected contexts, as in this example from the excellent PHD Comics

Out, Mad Colleague!

Posted in Uncategorized with tags , on January 30, 2012 by telescoper

In order to develop further the problem-solving skills of students in the School of Physics & Astronomy at Cardiff University, it has been decided to list the entries in the Spring Semester module catalogue in the form of anagrams.

For example, here is the list for third year students doing basic courses in physics SHY PICS







while those taking courses involving ROMAN TOYS also have



Students doing  SCUM I also get to do


and DECIMAL students have


Students also have to do their JET CROP, of course…

Oh, and  I forgot that 3rd year students can also take


I hope this clarifies the situation.

Take a stand against Elsevier

Posted in Open Access with tags , , , on January 29, 2012 by telescoper

My views about the academic journal racket are on record. Of all the profiteering outfits out there, the commercial publisher Elsevier  is one of the worst offenders, for the following reasons:

  1. They charge exorbitantly high prices for their journals.
  2. They sell journals in very large “bundles,” so libraries must buy a large set with many unwanted journals, or none at all. Elsevier thus makes huge profits by exploiting their essential titles, at the expense of other journals.
  3. They support measures such as SOPA, PIPA and the Research Works Act, that aim to restrict the free exchange of information.

I believe the business practices of Elsevier are detrimental to the open exchange of information on which scientific progress depends, so I have added my name to the list here of academics who refuse to publish in, referee for, or do editorial work on behalf of any Elsevier journal. If you wish to add your name to the list you can do so here.

A list of journals published by Elsevier can be found here.

I Don’t Like Chocolate

Posted in Uncategorized on January 29, 2012 by telescoper

I was beginning to think I’m the only person in the Universe who doesn’t like chocolate, so I’m grateful to this blogger for showing me I’m not alone!

Yesterday Cadbury were “promoting” their revolting “Creme Eggs” on Twitter. These are particularly vile: sickly sugar-soaked globules of a mixture of pus and mucus, encased in solidified baby poo. Eat one and puke.

I don’t like them, you see.

Shades of White Matter

I often wonder what chocolate tastes like to other people, because so many are so over the moon about it. My boss has a bowl of chocolate on his desk for public consumption, and people are constantly stopping by. Even if we’re in the office having a meeting, they’ll open the door and duck and grab, with a “Sorry, just needed chocolate.” It’s worse in the afternoon, and particularly on Wednesdays. It usually derails my train of thought, because I have to wonder why these people who would otherwise never be rude, in this case intrude just because they need chocolate. I look at the bowl and feel nothing.


It’s a burden sometimes, to be an anomaly. What, not like chocolate? If I had a dime for every time someone asked me why not, I could quit my job and never look at that chocolate bowl again. I have grown to…

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The H-index is Redundant…

Posted in Bad Statistics, Science Politics with tags , , , , , on January 28, 2012 by telescoper

An interesting paper appeared on the arXiv last week by astrophysicist Henk Spruit on the subject of bibliometric indicators, and specifically the Hirsch index (or H-index) which has been the subject of a number of previous blog posts on here. The author’s surname is pronounced “sprout”, by the way.

The H-index is defined to be the largest number H such that the author has written at least H papers having H citations. It can easily be calculated by looking up all papers by a given author on a database such as NASA/ADS, sorting them by (decreasing) number of citations, and working down the list to the point where the number of citations of a paper falls below the number representing position in the list. Normalized quantities – obtained by dividing the number of citations a paper receives by the number of authors of that paper for each paper – can be used to form an alternative measure.

Here is the abstract of the paper:

Here are a couple of graphs which back up the claim of a near-perfect correlation between H-index and total citations:

The figure shows both total citations (right) and normalized citations (left); the latter, in my view, a much more sensible measure of individual contributions. The basic problem of course is that people don’t get citations, papers do. Apportioning appropriate credit for a multi-author paper is therefore extremely difficult. Does each author of a 100-author paper that gets 100 citations really deserve the same credit as a single author of a paper that also gets 100 citations? Clearly not, yet that’s what happens if you count total citations.

The correlation between H index and the square root of total citation numbers has been remarked upon before, but it is good to see it confirmed for the particular field of astrophysics.

Although I’m a bit unclear as to how the “sample” was selected I think this paper is a valuable contribution to the discussion, and I hope it helps counter the growing, and in my opinion already excessive, reliance on the H-index by grants panels and the like. Trying to condense all the available information about an applicant into a single number is clearly a futile task, and this paper shows that using H-index and total numbers doesn’t add anything as they are both measuring exactly the same thing.

A very interesting question emerges from this, however, which is why the relationship between total citation numbers and h-index has the form it does: the latter is always roughly half of the square-root of the former. This suggests to me that there might be some sort of scaling law describing onto which the distribution of cites-per-paper can be mapped for any individual. It would be interesting to construct a mathematical model of citation behaviour that could reproduce this apparently universal property….

Gershwin, Adams & Rachmaninov

Posted in Music with tags , , , , , , , , on January 28, 2012 by telescoper

Yesterday (Friday) being the last day of (relative) freedom before teaching resumes on Monday I took the opportunity to go to a concert by the Orchestra of Welsh National Opera at the splendid St David’s Hall in Cardiff. I had been looking forward to it for some time, as the programme featured two favourite pieces of mine, George Gershwin’s Rhapsody in Blue and John Adams’ The Chairman Dances (A Foxtrot for Orchestra), plus one longer piece that I’ve never heard live before, Symphony No. 2 (in E minor) by Sergei Rachmaninov.

There was a good crowd in St David’s last night, not surprisingly given the popularity of the pieces being performed. Conductor for the evening was Frédéric Chaslin, who led the orchestra from the piano during the opening number, Rhapsody in Blue. This is a very famous piece, and is played so often that it is in danger of becoming a bit of a cliché, especially when classical orchestras try too hard to sound like jazz musician; the piece was originally written for Paul Whiteman’s Orchestra. A case in point is the opening clarinet solo, which is often played like a ham-fisted parody. Not last night, though. Principal clarinettist of WNO Leslie Craven gave a very characterful rendition of the notoriously tricky opening, which seemed to inspire the orchestra into an excellent all-round performance. I particularly enjoyed seeing the cello section slapping the strings of their instruments much as a jazz-era double-bass player would.

Chaslin gave an idiosyncratic account of the piano part, to the extent that in the final solo passage before the finale he departed from the script entirely and interpolated an improvised section all of his own. Not everyone in the audience approved – there were a few tuts behind me – but it’s a piece undoubtedly inspired by jazz, so I don’t see anything wrong with doing this. I thought his ad-libbing was charming, and very witty. What I wasn’t so happy about were the changes in tempo, which were too exaggerated. I suppose conducting from the piano means you can do whatever you want, but I think he took the rubato too far. Some sections rely on strict rhythm for their sense of urgency, and I felt he got bogged down a bit in places. Still, on balance, it was very refreshing to hear an orchestra trying to do something different. Nothing hackneyed about last night’s performance, that’s for sure.

Next one up was The Chairman Dances by John Adams. This isn’t actually in the opera Nixon in China, which is what a lot of people seem to think. It was composed at the same time, but cut out and developed as a standalone concert piece. I posted a recording of this yesterday, so won’t say too much today, except that I thoroughly enjoyed my first live experience of this work. So did the orchestra by the look of it! It’s a hugely entertaining piece and had many in the audience tapping their feet along with it. As a matter of fact, I wouldn’t have minded getting up and dancing along myself..

Special mention has to go the percussion section of the orchestra for doing such an excellent job. The four xylophones were  a delight to listen to, and the drums, temple blocks, triangles and assorted ironmongery coped brilliantly with the intricate polyrhythms.

Then it was the interval, and a glass of wine before returing to savour the main piece of the evening, Rachmaninov’s Second Symphony. It’s a remarkable work because it’s not only a “proper” symphony in its construction and development but also the best part of an hour of one glorious melody after another. Rachmaninov’s music is not really very much like Mozart, but they certainly had a similar ear for the Big Tune! I particularly loved the third movement (Adagio), but I thought it was a magnificent performance throughout, not least because you could see how much both conductor and orchestra were enjoying themselves.

The end of the concert was met with rapturous applause from the (normally rather reticent) St Davids audience. Now I have to find the best recording I can of Rachmaninov’s Second Symphony so I can enjoy it again. Any suggestions?

Foxtrot for Orchestra

Posted in Music with tags , on January 27, 2012 by telescoper

Sitting in the office at the end of a long week, and looking forward to going to an interesting-sounding concert at St David’s Hall later on. I may get the chance to review it over the weekend, but in the meantime I thought I’d put up this version of one of the pieces I’m going to hear later. I think it’s great but I’ve never heard it live…