Archive for the Science Politics Category

Uncertainty, Risk and Probability

Posted in Bad Statistics, Science Politics with tags , , , , , , , , on March 2, 2015 by telescoper

Last week I attended a very interesting event on the Sussex University campus, the Annual Marie Jahoda Lecture which was given this year by Prof. Helga Nowotny a distinguished social scientist. The title of the talk was A social scientist in the land of scientific promise and the abstract was as follows:

Promises are a means of bringing the future into the present. Nowhere is this insight by Hannah Arendt more applicable than in science. Research is a long and inherently uncertain process. The question is open which of the multiple possible, probable or preferred futures will be actualized. Yet, scientific promises, vague as they may be, constitute a crucial link in the relationship between science and society. They form the core of the metaphorical ‘contract’ in which support for science is stipulated in exchange for the benefits that science will bring to the well-being and wealth of society. At present, the trend is to formalize scientific promises through impact assessment and measurement. Against this background, I will present three case studies from the life sciences: assisted reproductive technologies, stem cell research and the pending promise of personalized medicine. I will explore the uncertainty of promises as well as the cunning of uncertainty at work.

It was a fascinating and wide-ranging lecture that touched on many themes. I won’t try to comment on all of them, but just pick up on a couple that struck me from my own perspective as a physicist. One was the increasing aversion to risk demonstrated by research funding agencies, such as the European Research Council which she helped set up but described in the lecture as “a clash between a culture of trust and a culture of control”. This will ring true to any scientist applying for grants even in “blue skies” disciplines such as astronomy: we tend to trust our peers, who have some control over funding decisions, but the machinery of control from above gets stronger every day. Milestones and deliverables are everything. Sometimes I think in order to get funding you have to be so confident of the outcomes of your research to that you have to have already done it, in which case funding isn’t even necessary. The importance of extremely speculative research is rarely recognized, although that is where there is the greatest potential for truly revolutionary breakthroughs.

Another theme that struck me was the role of uncertainty and risk. This grabbed my attention because I’ve actually written a book about uncertainty in the physical sciences. In her lecture, Prof. Nowotny referred to the definition (which was quite new to me) of these two terms by Frank Hyneman Knight in a book on economics called Risk, Uncertainty and Profit. The distinction made there is that “risk” is “randomness” with “knowable probabilities”, whereas “uncertainty” involves “randomness” with “unknowable probabilities”. I don’t like these definitions at all. For one thing they both involve a reference to “randomness”, a word which I don’t know how to define anyway; I’d be much happier to use “unpredictability”. Even more importantly, perhaps, I find the distinction between “knowable” and “unknowable” probabilities very problematic. One always knows something about a probability distribution, even if that something means that the distribution has to be very broad. And in any case these definitions imply that the probabilities concerned are “out there”, rather being statements about a state of knowledge (or lack thereof). Sometimes we know what we know and sometimes we don’t, but there are more than two possibilities. As the great American philosopher and social scientist Donald Rumsfeld (Shurely Shome Mishtake? Ed) put it:

“…as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns – the ones we don’t know we don’t know.”

There may be a proper Bayesian formulation of the distinction between “risk” and “uncertainty” that involves a transition between prior-dominated (uncertain) and posterior-dominated (risky), but basically I don’t see any qualititative difference between the two from such a perspective.

Anyway, it was a very interesting lecture that differed from many talks I’ve attended about the sociology of science in that the speaker clearly understood a lot about how science actually works. The Director of the Science Policy Research Unit invited the Heads of the Science Schools (including myself) to dinner with the speaker afterwards, and that led to the generation of many interesting ideas about how we (I mean scientists and social scientists) might work better together in the future, something we really need to do.

Yes, science produces too many PhDs

Posted in Science Politics with tags , , , , , on February 19, 2015 by telescoper

I came across a blog post this morning entitled Does Science Produce Too Many PhDs? I think the answer is an obvious “yes” but I’ll use the question as an excuse to rehash an argument I have presented before, which is that most analyses of the problems facing yearly career researchers in science are looking at the issue from the wrong end. I think the crisis is essentially caused by the overproduction of PhDs in this field. To understand the magnitude of the problem, consider the following.

Assume that the number of permanent academic positions in a given field (e.g. astronomy) remains constant over time. If that is the case, each retirement (or other form of departure) from a permanent position will be replaced by one, presumably junior, scientist.

This means that over an academic career, on average, each academic will produce just one PhD who will get a permanent job in academia. This of course doesn’t count students coming in from abroad, or those getting faculty positions abroad, but in the case of the UK these are probably relatively small corrections.

Under the present supply of PhD studentships an academic can expect to get a PhD student at least once every three years or so. At a minimum, therefore, over a 30 year career one can expect to have ten PhD students. A great many supervisors have more PhD students than this, but this just makes the odds worse. The expectation is that only one of these will get a permanent job in the UK. The others (nine out of ten, according to my conservative estimate) above must either leave the field or the country to find permanent employment.

The arithmetic of this situation is a simple fact of life, but I’m not sure how many prospective PhD students are aware of it. There is still a reasonable chance of getting a first postdoctoral position, but thereafter the odds are stacked against them.

The upshot of this is we have a field of understandably disgruntled young people with PhDs but no realistic prospect of ever earning a settled living working in the field they have prepared for. This problem has worsened considerably in recent  years as the number of postdoctoral positions has almost halved since 2006. New PhDs have to battle it out with existing postdoctoral researchers for the meagre supply of suitable jobs. It’s a terrible situation.

Now the powers that be – in this case the Science and Technology Facilities Council – have consistently argued that the excess PhDs go out into the wider world and contribute to the economy with the skills they have learned. That may be true in a few cases. However, my argument is that the PhD is not the right way to do this because it is ridiculously inefficient.

What we should have is a system wherein we produce more and better trained Masters level students  and fewer PhDs. This is the system that exists throughout most of Europe, in fact, and the UK is actually committed to adopt it through the Bologna process.  Not that this commitment seems to mean anything, as precisely nothing has been done to harmonize UK higher education with the 3+2+3 Bachelors+Masters+Doctorate system Bologna advocates.

The training provided in a proper two-year Masters programme will improve the skills pool for the world outside academia, and also better prepare the minority of students who go on to take a PhD. The quality of the  PhD will also improve, as only the very best and most highly motivated researchers will take that path. This used to be what happened, of course, but I don’t think it is any longer the case.

The main problem with this suggestion is that it requires big changes to the way both research and teaching are funded. The research councils turned away from funding Masters training many years ago, so I doubt if they can be persuaded to to a U-turn now. Moreover, the Research Excellence Framework provides a strong incentive for departments to produce as many PhDs as they possibly can, as these are included in an algorithmic way as part of the score for “Research Environment”. The more PhDs a department produces, the higher it will climb in the league tables. One of my targets in my current position is to double the number of PhDs produced by my School over the period 2013-18. What happens to the people concerned seems not to be a matter worthy of consideration. They’re only “outputs”…

The Impact of Impact

Posted in Science Politics with tags , on February 18, 2015 by telescoper

telescoper:

Interesting analysis of the 2014 REF results by my colleague Seb Oliver. Among other things, it shows that Physics was the subject in which “Impact had the greatest impact”..

Originally posted on Seb Boyd:

 The Impact of Impact

I wrote the following article to explore how Impact in the Research Excellence Framework 2014 (REF2014) affected the average scores of departments (and hence rankings). This produced a “league table” of how strongly impact affected different subjects. Some of the information in this article was used in a THE article by Paul Jump due to come out 00:00 on 19th Feb 2015.  I’ve now also produced ranking tables for each UoA using the standardised weighting I advocate below (see Standardised Rankings).

UoA Unit of Assessment Effective Weight of GPA

ranking in each sub-profile as %

Outputs Impact Envir.
9 Physics 37.9 38.6 23.5
23 Sociology 34.1 38.6 27.3
10 Mathematical Sciences 37.6 37.5 24.9
24 Anthropology and Development Studies 40.2 35.0 24.8
6 Agriculture, Veterinary and Food Science 42.0 33.0 25.0
31 Classics 43.3 32.6 24.0
16 Architecture, Built Environment and Planning 48.6 31.1 20.3

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The real decline of UK research funding..

Posted in Science Politics with tags , , on February 12, 2015 by telescoper

I saw a news item the other day about a report produced by the Royal Society, the British Academy, the Royal Academy of Engineering and the Academy of Sciences calling for a big uplift in research spending. Specifically,

A target for investment in R&D and innovation of 3% of GDP for the UK as a whole – 1% from the government and 2% from industry and charities – in line with the top 10 OECD research investors. The government currently invests 0.5% of GDP; with 1.23% from the private sector.

For reference here is the UK’s overall R&D spending as a fraction of GDP since from 2000 to 2012 as a fraction of GDP:

 

PublicFunding2000_2012

Some people felt that scientific research funding has done relatively well over the past few years in an environment of deep cuts in government funding in other areas. Iit has been protected against a steep decline in funding by a “ring fence” which has kept spending level in cash terms. Although inflation as measured by the RPI has been relatively low in recent years, the real costs of scientific research have been much faster than these measures. Here is a figure that shows the effective level of funding since the last general election that shows the danger to the UK’s research base:

flatcash

As a nation we already spend far less than we should on research and development, and this figure makes it plain that we are heading in the wrong direction. It’s not just a question of government funding either. UK businesses invest far too little in developing products and services based on innovations in science and technology. Because of this historic underfunding, UK based research has evolved into a lean and efficient machine but even such a machine needs fuel to make it work and the fuel is clearly running out…

Science, Art and The Song of the Lyre Bird

Posted in Biographical, Science Politics, The Universe and Stuff with tags , , , , , , , on February 10, 2015 by telescoper

I’ve posted this before but I thought I would do so again, just because it’s so marvellous.

I wonder what you felt as you watched it?  What went through your mind? Amusement? Fascination?  I’ll tell you how it was for me when I first saw it.  I marvelled.

Seeing the extraordinary behaviour of this incredible creature filled me with a sense of wonder. But I also began to wonder in another sense too. How did the Lyre Bird evolve its bizarre strategy? How does it learn to be such an accurate mimic? How does it produce such a fascinating variety of sounds? How can there be an evolutionary advantage in luring a potential mate to the sound of foresters and a chainsaw?

The Lyre Bird deploys its resources in such an elaborate and expensive way that you might be inclined to mock it, if all it does is draw females to “look at its plumes”.  I can think of quite a few blokes who adopt not-too-dissimilar strategies, if truth be told. But if you could ask a Lyre Bird it would probably answer that it does this because that’s what it does. The song defines the bird. That’s its nature.

I was moved to post the clip some time ago in response to a characteristically snide and ill-informed piece by Simon Jenkins in the Guardian. Jenkins indulges in an anti-science rant every now and again. Sometimes he has a point, in fact. But that article was just puerile. Perhaps he had a bad experience of science at school and never got over it.

I suppose I can understand why some people are cynical about scientists stepping into the public eye to proselytise about science. After all, it’s also quite easy to come up with examples of  scientists who have made mistakes. Sadly, there are also cases of outright dishonesty. The inference is that science is no good because scientists are fallible. But scientists are people, no better and no worse than the rest. To err is human and all that.  We shouldn’t expect scientists to be superhuman any more than we should believe the occasional megalomaniac who says they are.

To many people fundamental physics is a just a load of incomprehensible gibberish, the Large Hadron Collider a monstrous waste of money, and astronomy of no greater value to the world than astrology. Any scientist trying to communicate science to the public must be trying to hoodwink them, to rob them of the schools and hospitals that their taxes should be building and sacrifice their hard-earned income on the altar of yet another phoney religion.

And now the BBC is participating in this con-trick by actually broadcasting popular programmes about science that have generated huge and appreciative audiences. Simon Jenkins obviously feels threatened by it. He’s probably not alone.

I don’t  have anything like the public profile of the target of Jenkins’ vitriol, Lord Rees, but I try to do my share of science communication. I give public lectures from time to time and write popular articles, whenever I’m asked. I also answer science questions by email from the general public, and some of the pieces I post on here receive a reasonably wide distribution too.

Why do I (and most of my colleagues) do all this sort of stuff? Is it because we’re after your money?  Actually, no it isn’t. Not directly, anyway.

I do all this stuff because, after 25 years as a scientist, I still have a sense of wonder about the universe. I want to share that as much as I can with others. Moreover,  I’ve been lucky enough to find a career that allows me to get paid for indulging my scientific curiosity and I’m fully aware that it’s Joe Public that pays for me to do it. I’m happy they do so, and happier still that people will turn up on a rainy night to hear me talk about cosmology or astrophysics. I do this because I love doing science, and want other people to love it  too.

Scientists are wont to play the utilitarian card when asked about why the public should fund fundamental research. Lord Rees did this in his Reith Lectures, in fact. Physics has given us countless spin-offs – TV sets, digital computers,  the internet, you name it – that have created wealth for UK plc out of all proportion to the modest investment it has received. If you think the British government spends too much on science, then perhaps you could try to find the excessive sum on this picture.

Yes, the LHC is expensive but the cost was shared by a large number of countries and was spread over a long time. The financial burden to the UK now amounts to the cost of a cup of coffee per year for each taxpayer in the country. I’d compare this wonderful exercise in friendly international cooperation with the billions we’re about to waste on the Trident nuclear weapons programme which is being built on the assumption that international relations must involve mutual hatred.

This is the sort of argument that gets politicians interested, but scientists must be wary of it. If particle physics is good because it has spin-offs that can be applied in, e.g. medicine, then why not just give the money to medical research?

I’m not often put in situations where I have to answer questions like why we should spend money on astronomy or particle physics but, when I am, I always feel uncomfortable wheeling out the economic impact argument. Not because I don’t believe it’s true, but because I don’t think it’s the real reason for doing science. I know the following argument won’t cut any ice in the Treasury, but it’s what I really think as a scientist (and a human being).

What makes humans different from other animals? What defines us? I don’t know what the full answer to that is, or even if it has a single answer, but I’d say one of the things that we do is ask questions and try to answer them. Science isn’t the only way we do this. There are many complementary modes of enquiry of which the scientific method is just one. Generally speaking, though, we’re curious creatures.

I think the state should support science but I also think it should support the fine arts, literature, humanities and the rest, for their own sake. Because they’re things we do. They  make us human. Without them we’re just like any other animal that consumes and reproduces.

So the real reason why the government should support science is the song of the Lyre Bird.  No, I don’t mean as an elaborate mating ritual. I don’t think physics will help you pull the birds. What I mean is that even in this materialistic, money-obsessed world we still haven’t lost the  need to wonder, for the joy it brings and for the way it stimulates our minds; science doesn’t inhibit wonder, as Jenkins argues,  it sparks it.

Now, anyone want to see my plumes?

A whole lotta cheatin’ going on? REF stats revisited

Posted in Education, Science Politics with tags , , , on January 28, 2015 by telescoper

telescoper:

Here’s a scathing analysis of Research Excellence Framework. I don’t agree with many of the points raised and will explain why in a subsequent post (if and when I get the time), but I reblogging it here in the hope that it will provoke some comments either here or on the original post (also a wordpress site).

Originally posted on coastsofbohemia:

 

1.

The rankings produced by Times Higher Education and others on the basis of the UK’s Research Assessment Exercises (RAEs) have always been contentious, but accusations of universities’ gaming submissions and spinning results have been more widespread in REF2014 than any earlier RAE. Laurie Taylor’s jibe in The Poppletonian that “a grand total of 32 vice-chancellors have reportedly boasted in internal emails that their university has become a top 10 UK university based on the recent results of the REF”[1] rings true in a world in which Cardiff University can truthfully[2]claim that it “has leapt to 5th in the Research Excellence Framework (REF) based on the quality of our research, a meteoric rise” from 22nd in RAE2008. Cardiff ranks 5th among universities in the REF2014 “Table of Excellence,” which is based on the GPA of the scores assigned by the REF’s “expert panels” to the three…

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Lognormality Revisited

Posted in Biographical, Science Politics, The Universe and Stuff with tags , , , , , on January 14, 2015 by telescoper

I was looking up the reference for an old paper of mine on ADS yesterday and was surprised to find that it is continuing to attract citations. Thinking about the paper reminds me off the fun time I had in Copenhagen while it was written.   I was invited there in 1990 by Bernard Jones, who used to work at the Niels Bohr Institute.  I stayed there several weeks over the May/June period which is the best time of year  for Denmark; it’s sufficiently far North (about the same latitude as Aberdeen) that the summer days are very long, and when it’s light until almost midnight it’s very tempting to spend a lot of time out late at night..

As well as being great fun, that little visit also produced what has turned out to be  my most-cited paper. In fact the whole project was conceived, work done, written up and submitted in the space of a couple of months. I’ve never been very good at grabbing citations – I’m more likely to fall off bandwagons rather than jump onto them – but this little paper seems to keep getting citations. It hasn’t got that many by the standards of some papers, but it’s carried on being referred to for almost twenty years, which I’m quite proud of; you can see the citations-per-year statistics even seen to be have increased recently. The model we proposed turned out to be extremely useful in a range of situations, which I suppose accounts for the citation longevity:

lognormal

I don’t think this is my best paper, but it’s definitely the one I had most fun working on. I remember we had the idea of doing something with lognormal distributions over coffee one day,  and just a few weeks later the paper was  finished. In some ways it’s the most simple-minded paper I’ve ever written – and that’s up against some pretty stiff competition – but there you go.

Picture1

The lognormal seemed an interesting idea to explore because it applies to non-linear processes in much the same way as the normal distribution does to linear ones. What I mean is that if you have a quantity Y which is the sum of n independent effects, Y=X1+X2+…+Xn, then the distribution of Y tends to be normal by virtue of the Central Limit Theorem regardless of what the distribution of the Xi is  If, however, the process is multiplicative so  Y=X1×X2×…×Xn then since log Y = log X1 + log X2 + …+log Xn then the Central Limit Theorem tends to make log Y normal, which is what the lognormal distribution means.

The lognormal is a good distribution for things produced by multiplicative processes, such as hierarchical fragmentation or coagulation processes: the distribution of sizes of the pebbles on Brighton beach  is quite a good example. It also crops up quite often in the theory of turbulence.

I’ll mention one other thing  about this distribution, just because it’s fun. The lognormal distribution is an example of a distribution that’s not completely determined by knowledge of its moments. Most people assume that if you know all the moments of a distribution then that has to specify the distribution uniquely, but it ain’t necessarily so.

If you’re wondering why I mentioned citations, it’s because it looks like they’re going to play a big part in the Research Excellence Framework, yet another new bureaucratical exercise to attempt to measure the quality of research done in UK universities. Unfortunately, using citations isn’t straightforward. Different disciplines have hugely different citation rates, for one thing. Should one count self-citations?. Also how do you aportion citations to multi-author papers? Suppose a paper with a thousand citations has 25 authors. Does each of them get the thousand citations, or should each get 1000/25? Or, put it another way, how does a single-author paper with 100 citations compare to a 50 author paper with 101?

Or perhaps the REF panels should use the logarithm of the number of citations instead?

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