The BrisScience lecture series is on again (Monday 15th at City Hall, 6:30 pm), and both the topic and speaker are closer to home than usual. The topic is Water in South East Queensland. The speaker, Professor Paul Greenfield, is about to become Vice-Chancellor of the University of Queensland.
More details here and over the fold
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One of the stranger efforts of the political right over the last decade has been the effort to paint Rachel Carson as a mass murderer, on the basis of bogus claims conflating the US ban on non-public health uses of DDT with a non-existent ban on the use of DDT as an antimalarial. Starting from the lunatic fringe of the LaRouche movement and promoted primarily by current and retired hacks for the tobacco industry, this claim has become received wisdom throughout the US Republican party and its received offshoots. Although this nonsense has been comprehensively demolished by bloggers, most notably Tim Lambert, article-length refutations are desperately needed. Now Aaron Swartz has a piece published in Extra!. It’s great to see this but, as the global warming debate has shown, one refutation is never enough in resisting the Republican War on Science.
Over at Cosmic Variance, physicist Sean Carroll offers some admittedly uninformed speculation about utility theory and economics, saying
Anyone who actually knows something about economics is welcome to chime in to explain why all this is crazy (very possible), or perfectly well-known to all working economists (more likely), or good stuff that they will steal for their next paper (least likely). The freedom to speculate is what blogs are all about.
I didn’t notice anything crazy but there’s a fair bit that’s well-known. For example, Carroll observes that utility is generally not additive across commodities, and that some goods are likely to be more closely related than others. That’s textbook stuff, covered by the basic concepts of complementarity and substitutability.
This is a more interesting and significant point
But I’d like to argue something a bit different — not simply that people don’t behave rationally, but that “rational� and “irrational� aren’t necessarily useful terms in which to think about behavior. After all, any kind of deterministic* behavior — faced with equivalent circumstances, a certain person will always act the same way — can be modeled as the maximization of some function. But it might not be helpful to think of that function as utility, or as the act of maximizing it as the manifestation of rationality.
I can only agree. But economists and (even more, I think) political scientists in the “rational choice” tradition regularly get themselves tied up in all sorts of knots about this, switching between the trivial notion of maximising a function and substantive claims in which rationality is frequently equated with egoism. Joseph Butler demolished this kind of reasoning nearly 300 years ago, but it keeps on popping up.
* This qualification isn’t necessary, and Carroll notes later on that choices are often stochastic. The resulting probability distributions still maximise an appropriately defined function.
Until recently, the American Association of Petroleum Geologists was the only significant scientific organization with an official position rejecting anthropogenic global warming. Issued in 1999, it claimed that “Recently published research results do not support the supposition of an anthropogenic cause of global climate change”. AAPG has abandoned that position and issued a new position statement.
The new position statement is equivocal, beginning with the observation that “the AAPG membership is divided on the degree of influence that anthropogenic CO2 has on recent and potential global temperature increases”, and going on to say “Certain climate simulation models predict that the warming trend will continue, as reported through NAS, AGU, AAAS, and AMS. AAPG respects these scientific opinions but wants to add that the current climate warming projections could fall within well-documented natural variations in past climate and observed temperature data.”
Still, its a big advance on the embrace of delusionism that led to the 1999 statement and to the embarrassing decision in 2006 to give a science journalism award to Michael Crichton. Of course, this will have no effect on those who get their science from fiction writers, opinion columnists and rightwing thinktanks, but it’s encouraging nonetheless.
It’s on tonight. After a week of welcome rain (floods where we didn’t need it, much lighter where we did, but that’s the way it goes) skies should be clear here in Queensland.
Also on science, last night’s Bris Science lecture on bees was fascinating. It seems bees use the apparent motion of the ground and nearby objects to perform feats like navigating through tight spots, landing smoothly and estimating distance travelled. This suggests some simple algorithms that can be used, for example, by automated vehicles on land and in the air. The PowerPoint presentation should be up at the BrisScience site soon.
Update I spoke too soon, especially considering my generally poor record with astronomical events. It was cloudy after all, though not so as to prevent a reasonable view of the moon going a copper-red colour as advertised.
BrisScience on Monday 27th will deal with how bees do such amazing stuff with tiny brains. Details over the fold
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BrisScience on Monday 27th will deal with how bees do such amazing stuff with tiny brains. Details over the fold
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That’s the title of tonight’s talk in the BrisScience program to be presented by # Wilson da Silva, Editor of Cosmos Magazine
# Date: Monday July 23, 2007
# Time: 6:30pm to 7:30pm
# Venue: Ithaca auditorium, City Hall
More details over the page and here
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The question of disciplinary boundaries is a perennial, and Brian Weatherson’s CT post on Richard Gott’s Copernican principle provides yet another instance. Gott, an astrophysicist, is interested in the question of whether you can infer the future duration of a process from its present age, and this issue seems to received some discussion in philosophy journals.
It may be beneath the notice of these lofty souls, but statisticians and social scientists have actually spent a fair bit of time worrying about this question of survival analysis (also called duration analysis). For example, my labour economist colleagues at ANU were very interested in the question of how to infer the length of unemployment spells, based on observations of how long currently unemployed people had actually been unemployed. The same question arises in all sorts of contexts (crime and recidivism, working life of equipment, individual life expectancy and so on). Often, the data available is a set of incomplete durations, and you need to work out the implied survival pattern.
Given a suitably large sample (for example, the set of observations of Broadway plays, claimed as a successful application of Gott’s principle) this is a tricky technical problem, and requires some assumptions about entry rates, but raises no fundamental logical difficulties. The problem is to find a distribution that fits the data reasonably well and estimate its parameters. I don’t imagine anyone doing serious work in this field would be much impressed by Gott’s apparent belief that imposing a uniform distribution for each observation is a good way to go.
Former Surgeon General Richard H. Carmona, a Bush appointee, has told a Congressional committee that “top officials in the Bush administration repeatedly tried to weaken or suppress important public health reports because of political considerations.”
This isn’t news to anyone who’s been paying attention, but it does demonstrate, yet again, that it’s impossible to be pro-Republican and pro-science at the same time. This isn’t just a matter of the Bush administration. Every important element of the Republican base is anti-science, as are all the main pro-Republican thinktanks, blogs and so on. The issues differ from group to group (the religious right focuses on evolution and stem cells, libertarians on global warming and passive smoking, the business base on more specific environmental and public health regulation) but all of them use the same kinds of arguments. The debating tricks used by global warming delusionists have been taken straight from the creationist playbook. More importantly, all of them take for granted the view that science is inherently political, and that what matters is getting the politics right.
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John Quiggin 