With kudos to Tim and Lynn for tackling AIC, I am deferring Jarrett’s challenge to us to consider the philosophical aspects of AIC and p-values for now, but will share some recent musings that fall somewhere under the “philosophy of statistics” heading.
The only area of BIOL 607 in which I have found myself consistently ahead of the assignments has been the Nate Silver readings and, in truth, it is not I but the Boston-area traffic that can claim credit for this state of affairs. To my delight The Signal and The Noise was available from Audible – meaning that I could actually do homework *and* keep my sanity through an hour and a half or more commute each way to and from UMass Boston. Listening to audiobooks directs my brain’s main attention to the substance of the text while leaving the autopilot part of my brain to deal with the “do not run into the car in front of you and watch out for the bozo cutting in from the right” kind of work. It has been a most successful partnership between the higher level thinking processes and the gut survival instincts resulting in long rides that do not raise my blood pressure nor leave me wanting to abandon my car in the middle of the road due to an attack of traffic-induced claustrophobia. So I finished The Signal and the Noise some weeks back, along with Greenberg’s Four Fish, Corson’s The Secret Life of Lobsters, and Safina’s Song for the Blue Ocean, all of which I strongly recommend.
Back to statistics – I found myself thinking that Silver takes a more benign view of both the Wall Street financial players and the climate change skeptics than do I. In his first chapter on the financial meltdown, Silver’s analysis at times borders on rather a whitewash given his focus on the hidden risks, poor assessment of probabilities and statistical errors in the models used by financial firms and ratings agencies in the lead up to the 2008 crash. So here is where the philosophy part comes in – to what degree does one attribute the Lehman meltdown, the AIG meltdown etc. as caused primarily by ignorance – in the form of poor modeling and poor risk assessment etc. – and to what degree does one think that the majority of the very smart people involved knew quite well the inherent risks and knew that their models were bogus but figured they could get out or get away with it or at least not be left without a chair when the music inevitably stopped playing? I feel Silver at times is so focused on the probabilities, statistical models and process that he downplays the influence of deliberate, calculated human choices in determining outcomes. Not all bad choices derive from ignorance or poor models – many times less flattering aspects of human behavior are at work and subsequent evidence has uncovered just how aware of what they were doing most of the traders and firms involved really were.
Jumping ahead in The Signal and the Noise (spoiler alert!) to Chapter 12 on climate change modeling, I feel this same focus on statistical models and the intellectual challenges of statistics blinds Silver a bit in his treatment of climate change skeptics, most notably Scott Armstrong. Silver considers one of Armstrong’s books to be a seminal work within the statistics field and that may be why he gives Armstrong’s arguments more respect and legitimacy than I feel is due. As Silver acknowledges, Armstrong, like many of the prominent climate skeptics, hails from outside any scientific field directly related to understanding the earth’s climate system and the likely impacts of changes within that system (Armstrong is an economist and proclaims his ignorance of climate science almost proudly when before a Senate hearing).
Apart from any role that personal/professional ambition or ego might play, Armstrong has a particular economic, social and political view of the world that strongly influences his views on climate change and more importantly, his views on those in society advocating laws, regulatory changes, and government action to combat climate change. But Armstrong’s jabs against anthropogenic climate change are not the product of scientific knowledge and one has to do only a little digging to realize Armstrong is strongly aligned with the hardcore climate change deniers. He is one of the signatories of the now infamous Cato Institute (founded and funded by the Koch Brothers) full-page ad that appeared in prominent newspapers around the country in 2009 [read the ad at http://www.cato.org/special/climatechange/cato_climate.pdf ]. Silver’s serious treatment of Armstrong and other skeptics gives them an unearned legitimacy. It makes me think of the segment on Last Week Tonight with John Oliver, when, with the help of Bill Nye, Oliver makes the point that the news media tries so hard to be “neutral” and to provide both sides airtime and to treat both sides of the matter equally that, ironically, the news media ends up presenting a distorted view to the public that makes it seem like the reality of climate change is still being debated seriously.
Ultimately, truth wins out. But in the short-term, the “truthiness” of statistics and statistical modeling lie very much in the choices made by the human practitioners, and sometimes truth and the advancement of human knowledge takes a back seat to stronger drivers.