Archive for the Uncategorized Category

inflation, evidence and falsifiability

Posted in Uncategorized on July 27, 2015 by telescoper

telescoper:

At the risk of labouring the point here’s another critque of the Gubitosi et al, paper I posted about a couple of days ago…

Originally posted on Xi'an's Og:

[Ewan Cameron pointed this paper to me and blogged about his impressions a few weeks ago. And then Peter Coles wrote a (properly) critical blog entry yesterday. Here are my quick impressions, as an add-on.]

“As the cosmological data continues to improve with its inevitable twists, it has become evident that whatever the observations turn out to be they will be lauded as proof of inflation”.”G. Gubitosi et al.

In an arXive with the above title, Gubitosi et al. embark upon a generic and critical [and astrostatistical] evaluation of Bayesian evidence and the Bayesian paradigm. Perfect topic and material for another blog post!

“Part of the problem stems from the widespread use of the concept of Bayesian evidence and the Bayes factor (…) The limitations of the existing formalism emerge, however, as soon as we insist on falsifiability as a pre-requisite for a scientific theory (….) the…

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On (un)falsifiability of paradigms with Bayesian model selection …

Posted in Uncategorized on July 25, 2015 by telescoper

telescoper:

Yesterday’s post is generating quite a lot if traffic for a weekend so I thought I would reblog this piece on the same topic..

Originally posted on Another Astrostatistics Blog:

I noticed an unusual contribution on the philosophy of science with Bayesian model selection by Gubitosi et al. on astro ph the other day, in which some rather bold claims are made, e.g.

“By considering toy models we illustrate how unfalsifiable models and paradigms are always favoured by the Bayes factor.”

Despite the authors making a number of sniping comments about the sociology of “proof of inflation” claims in astronomy, their meta-reflections did not reach a point of self-awareness at which they were able to escape my own sociological observation: the bolder the claims made by astronomers about Bayes theorem, the narrower their reading of the past literature on the subject. Indeed, in this manuscript there are no references at all to any previous work on the role of Bayes factors in scientific decision making, even from within the astronomical canon (leaving beside the history of statistics); more precisely, it…

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Why not doing research all the time can make you a better researcher

Posted in Uncategorized on July 5, 2015 by telescoper

Yesterday I read a nice little article  in Nature about how doing something different from research every now and again can actually make you a better researcher. I agree with that completely, so thought I’d expand upon the theme with a few comments of my own. I think this is an issue of particular importance for early career researchers, as that is the stage at which good habits need to be established, so I will focus on PhD students.

The point is that a postgraduate research degree is very different from a programme of undergraduate study. For one thing, as a research student you are expected to work on your own a great deal of the time. That’s because nobody else will be doing precisely the same project so, although other students will help you out with some things, you’re not trying to solve the same problems as your peers as is the case with an undergraduate. Your supervisor will help you of course and make suggestions (of varying degrees of helpfulness), but a PhD is still a challenge that you have to meet on your own. I don’t think it is good supervisory practice to look over a research student’s shoulder all the time. It’s part of the purpose of a PhD that the student learns to go it alone. There is a balance of course, but my own supervisor was rather “hands off” and I regard that as the right way to supervise. I’ve always encouraged my own students to do things their own way rather than try to direct them too much.

The sense of isolation that can come from immersing yourself in research is tough in itself, but there’s also the scary fact that you do not usually know whether your problem has a solution, let alone whether you yourself can find it. There is no answer at the back of the book; if there were you would not be doing research. A good supervisor will suggest a project that he or she thinks is both interesting and feasible, but the expectation is that you will very quickly be in a position where you know more about that topic than your supervisor.

I think almost every research student goes through a phase in which they feel out of their depth. There are times when you get thoroughly stuck and you begin to think you will never crack it. Self-doubt, crisis of confidence, call it what you will, I think everyone who has done a postgraduate degree has experienced it. I certainly did. A year into my PhD I felt I was getting nowhere with the first problem I had been given to solve. All the other research students seemed much cleverer and more confident than me. Had I made a big mistake thinking I could this? I started to panic and began to think about what kind of job I should go into if I abandoned the idea of pursuing a career in research.

So why didn’t I quit?

There were a number of factors, including the support and encouragement of my supervisor, staff and fellow students in the Astronomy Centre, and the fact that I loved living in Brighton, but above all it was because I knew that I would feel frustrated for the rest of my life if I didn’t see it through. I’m a bit obsessive about things like that. I can never leave a crossword unfinished either.

But while it can be good to be a  obsessive about your research, that doesn’t mean you should try to exclude other things, even other obsessions, from your life.

What happened in my case was that after some discussion with my supervisor I shelved that first troublesome problem and tried another, much easier one. I cracked that fairly quickly and it became my first proper publication. Moreover, thinking about that other problem revealed that there was a way to finesse the difficulty I had failed to overcome in the first project. I returned to the first project and this time saw it through to completion. With my supervisor’s help that became my second paper, published in 1987.

I know it’s wrong to draw inferences about other people from one’s own particular experiences, but I do feel that there are general lessons. One is that if you are going to complete a research degree you have to have a sense of determination that borders on obsession. I was talking to a well-known physicist at a meeting not long ago and he told me that when he interviews prospective physics students he asks them “Can you live without physics?”. If the answer is “yes” then he tells them not to do a PhD. It’s not just a take-it-or-leave-it kind of job being a scientist. You have to immerse yourself in it and be prepared to put long hours in. When things are going well you will be so excited that you will find it as hard to stop as it is when you’re struggling. I’d imagine it is the just same for other disciplines.

The other, equally important, lesson to be learned is that it is essential to do other things as well. Being “stuck” on a problem is part-and-parcel of mathematics or physics research, but sometimes battering your head against the same thing for days on end just makes it less and less likely you will crack it. The human brain is a wonderful thing, but it can get stuck in a rut. One way to avoid this happening is to have more than one thing to think about.

I’ve lost count of the number of times I’ve been stuck on the last clue in a crossword. What I always do in that situation is put it down and do something else for a bit. It could even be something as trivial as making a cup of tea, just as long as I don’t think about the clue at all while I’m doing it. Nearly always when I come back to it and look at it afresh I can solve it. I have a large stack of prize dictionaries to prove that this works!

It can be difficult to force yourself to pause in this way. I’m sure that I’m not the only physicist who has been unable to sleep for thinking about their research. I do think however that it is essential to learn how to effect your own mental reboot. In the context of my PhD research this involved simply turning to a different research problem, but I think the same purpose can be served in many other ways: taking a break, going for a walk, playing sport, listening to or playing music, reading poetry, doing a crossword, or even just taking time out to socialize with your friends. Time spent sitting at your desk isn’t guaranteed to be productive.

So, for what it’s worth here is my advice to new postgraduate students. Work hard. Enjoy the challenge. Listen to advice from your supervisor, but remember that the PhD is your opportunity to establish your own identity as a researcher. Above all, in the words of the Desiderata:

Beyond a wholesome discipline,
be gentle with yourself.

Never feel guilty about establishing a proper work-life balance. Having more than one dimension to your life will not only improve your well-being but also make you a better researcher.

Introduction of me, my ideology and this blog

Posted in Uncategorized on July 4, 2015 by telescoper

telescoper:

A new blog about science education for students with special needs.

Why not give it a follow?

Originally posted on SENSE: Science Education as a Non-Sighted Experience:

If you look at the “About me” section of this set of articles, you will most probably find nothing. The reason for that is deep in the roots of the idea; it does not matter who I am. It does not matter what my name, age, gender is, that does not tell you a lot about me if you know I have long hair and green eyes. Similarly, it really doesn’t change much whether you know my nationality, profession, or the food, music I like. I would be too subjective and biased to introduce myself in words of descriptions, adjectives and attributes. Why don’t you tell me and retell others who I am, what I believe in, what I do, based on the things I say, think or in this case blog post.
I also wouldn’t want to write about me, simply because there are certainly more people thinking the…

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Open Day in the Sun

Posted in Uncategorized on June 27, 2015 by telescoper

Just back from a day on campus at an Open Day for potential students at Sussex University (and an afternoon getting on with work). I think the day went well, and it was nice to get some good weather for a change!

Anyway here’s a picture I took as things were starting to wind down this afternoon.

image

Now I am going to make myself something to eat and chill out with a glass of wine..

Reading Day

Posted in Uncategorized on June 26, 2015 by telescoper

Taking a day off. Work-life balance and all that. Still, I am making use of time by catching up on some reading..

image

Men in skirts? Why not?

Posted in Uncategorized on June 24, 2015 by telescoper

telescoper:

I’ve often thought that, especially in this weather, a skirt would be rather comfortable.

Anyone know where I might be able to buy a nice manly skirt?

Originally posted on :

I’ve always said that in the future men will wear skirts (dresses) as much as women. I’m still trying to explain myself why during all these centuries men didn’t dare to wear a skirt (respect goes to Scotland men)?

Wearing skirts has so many advantages – it’s comfortable, it makes your skin breathe, it gives you more freedom when you move… What is so wrong with that? Man have ugly legs? So what? There are lots of women with ugly legs too and they are allowed to wear skirts. Men have something women don’t (you know what I’m talking ’bout)? So what? It’s even more on show when they wear skinny jeans or any other tight kind of trousers – if you want to stare you stare!

Just don’t tell me that there must be something to make women and men different! As if you can’t distinguish a woman from…

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