Reading Group

In Uncategorized on May 17, 2010 by bcnjake

Greetings, PhilSci Types!

(Or, as Josh would say, Gentle PhilSciers)

Josh, Lynn, and I are putting together a little reading group for those who might be interested.  We’re reading Woodward’s Making Things Happen and will be meeting on Mondays at 5:00 at Uprise.  If you’re interested in taking part, email one of us and we’ll pass along the relevant information (what we’re reading that week, what the game plan is, etc.).  If you’re only interested in part of Woodward or can’t make it every week, no worries!  We’re happy to have you even for a week.


Wading into Akaike again…

In Uncategorized on May 5, 2010 by Randy

Apologies to all about my stridency during the seminar. I regret that much of our normal discourse was stifled by the red herring that I threw into the room.

Having said that…

Let me tell you two short stories in which Akaike figures. A few years ago, I sat in on a highly rigorous doctoral seminar on psychometrics taught by one of the giants in the field, Roderick P. McDonald. Causal modeling (does this sound scary to a philosopher?) for analysis of complex social science data was the overt subject matter. McDonald described his objective as to get us to the point where we “were not a danger to ourselves nor an an annoyance to others”. He took us through BIC and AIC, as well as 16 other criteria for assessing model fit given parsimony, included and omitted variables, number of cases (“n”), and the characteristics of the raw data. Long story short, AIC and BIC are unstable with respect to parsimony (number of parameters between competing models) and “n”. He called these two criteria “useless nonsense”, as were all the others for various faults with respect to the core criterion for model fit: the noncentrality parameter.

He also told a story of a meeting in 1972 where Akaike shared the dais with Joreskog (developer of LISREL – the standard statistical package for doing the kinds of analyses I alluded to above) and a doctoral student in education from the University of Chicago, J.W. Keesling. Keesling presented his thesis paper on causal flow modeling. His design looks  like Joreskog’s LISREL model a few years later. Sometime in the 1990’s practitioners of causal modeling began calling the design the Keesling-Wiley-Joreskog model (including Keesling’s mentor, David Wiley). I suspect Rod McDonald was more than just a casual observer of this more complete attribution of the analytical design. And Akaike’s information criterion, discussed at the same symposium, became a default goodness-of-fit measure for LISREL and its knock-offs. Big-time meeting — ex post.

Grad students: guard your intellectual property! And be skeptical of received wisdom of from philosophers who discuss parsimony in the ether without looking in the dirt where the concept is a core feature of practice.


Teaching Game Theory

In Uncategorized on May 5, 2010 by Randy

Another blog pointed me to a site where an enterprising graduate student has compiled 26 You Tube videos to teach game theory. The collection includes the stag hunt, battle of the sexes, and others that you have dealt with in boring prose and tedious extended form diagrams.


Higher- and Lower-level Science

In Uncategorized on May 4, 2010 by Randy

Further to our discussion last week!


Simplicity Discussion

In Class matters on May 4, 2010 by Jenny

While Forster’s “The New Science of Simplicity” is a nice introduction into using Akaike’s information criterion and Bayesian information criterion for adjudicating the trade-off between parsimony and goodness of fit in model selection, it won’t be the primary focus of tomorrow’s discussion.  For tomorrow, I want us to look really closely at Sober’s main argument in “Let’s Razor Ockham’s Razor.”  There’s a lot of good stuff in there.


Scientific Anarchism

In Discussion on April 30, 2010 by dcmzb8

Dan here. This post is way too long, but it’s as short as I can make it.

Thesis: We have *no* reason to think that *any* synthetic proposition is necessarily true, for any strong sense of necessary.

Beatty’s Evolutionary Contingency Thesis claims that there are no laws in biology, because it is possible to find exceptions to any distinctly biological generalization. When we find an exception to a law-like generalization, we can save it from falsification by modifying the antecedent of the generalization’s conditional so that it doesn’t apply in the case of the exception. Do this enough times, and you either have a conditional that belongs to a lower-level science, or an analytically true tautology. I don’t have a major problem with calling such a tautology a law, since I think this is merely a linguistic dispute. I would prefer to call such a tautology a model, not a law, but this is partly because I like the cool name for my position.

However, I think we might eventually be able to extend the ECT to lower levels of science. Take Hempel’s example of a law-like generalization: you can’t have a sphere of U-238 1 km in diameter (because the thing would explode!). Now consider the fine-tunning thesis. In our current physical theories, there are about 16 free parameters. These are constants where we have no theoretical basis for setting their values – they have to be obtained empirically. According to the fine-tunning thesis, stellar formation is only possible for a small range of the possible values for these free parameters. One possible explanation for this is that there is some processes that is creating a large number of universes (possibly infinite) with the values of the free parameters assigned randomly. We just happen to be in one of the very few universes that can support observers, otherwise, we wouldn’t be around to observe. So, if we could explore other universes, we would quickly find exceptions to Hempel’s U-238 generalization.

So, it might be the case that, for *any* synthetic proposition in our current body of theory, we will eventually discover that this proposition can only be explained by a set of analytically true conditionals (a model) + the very contingent empirical proposition that the model applies in this case.

As for nomic necessity: Per this hypothesis, all “laws” are contingent, and nomic ‘possibility” (which is defined in terms of holding scientific laws constant) means holding the contingency base that makes a given set of laws true constant between possible worlds. The trouble with biology is that we have nomic ‘impossibilities’ that are actual. At some point, this may be true for chemistry and physics as well. So, we will have to bite the bullet: accept that we can have actual nomic impossibilities, or let nomic necessity recede to the point that it resembles logical necessity.


Philosophy of science humor

In Uncategorized on April 28, 2010 by Pete Abram

From some random website with which I am not familiar comes a great satirical article: – I figured I’d post this after Andre went on about how horrible it is to side with Kuhn. Even though I do side with Kuhn, please, please, please do not accuse me of siding the the “Insane Clown Posse”.

The Insane Clown Posse Are Sane Proponents of Thomas Kuhn’s Paradigm Theory.

The Insane Clown Posse video, ‘Miracles,’ was recently posted on YouTube and has since become an internet meme due to its seemingly ignorant lyrics, specifically the following excerpt:

Water, fire air and dirt–f*cking magnets, how do they work? An’ I don’t wanna talk to a scientist; y’all muthaf*ckas lyin’ and gettin’ me pissed.

Many claim that the ICP is extolling the tenets of the anti-science movement, first introduced by Jean-Jacques Rousseau, specifically in his Discourse on the Arts and Sciences. This movement states that science can lead to moral corruption and arrogance. However, it seems that the ICP is not saying that science is worthless, but that truth is inherently unknowable. They are, it seems, students of the great sociologist Thomas Kuhn and his groundbreaking work The Structure of Scientific Revolutions.

Kuhn said that science, heretofore viewed as a progressive study, is in fact not progressive, but rather based on large-scale changes in thought and theory. For instance, Newton is one of the fathers of modern science, with his laws and equations still being taught in physics and calculus classes to this day. However, when Einstein theorized his relativistic physics, not only did his equations give better results than Newton’s, but by their mere existence showed that Newton’s equations were all wrong, merely approximations of the “truth.”

To put it simply, Kuhn stated that each one of these sets of beliefs was called a “paradigm.” And, when a paradigm exhibited enough anomalies, for instance the inability to apply Newtonian physics to sub-atomic motion, scientists would theorize a new paradigm to take the old one’s place. The upshot of this was that no paradigm in itself could be called truth. Rather, if the universe’s laws were a clock, a paradigm could only describe the motion of the hands; there was no way to see the gears themselves.

Joseph Bruce and Joseph Utsler AKA Violent J and Shaggy 2 Dope are simply claiming this with their lyrics, “magnets, how do they work?” The truth is the theory of magnetism has changed wildly over the decades and is still veiled in a certain amount of mystery. Sure, scientists know how to use magnets, how to measure magnetic force, even how to chart magnetic fields, but to actually explain that force is to create a unified field theorem which remains the unfound Holy Grail in scientific research. Scientists themselves do not really know how magnets work. What they have now is simply a paradigmatic explanation of magnetism.

And in terms of scientists “lyin’,” here again the ICP is repeating their belief that scientists remain hard-headedly in support of a certain paradigm and it is often left to the next generation of scientists to have the flexibility of thought to accept a better fitting paradigm.

Although Violent J and Shaggy 2 Dope may have never read Kuhn’s works, those who suggest that their raps are ignorant haven’t been properly educated in scientific theory and sociology. For, if they had been, they would know that the ICP is not ignorant. Far from it: they are keeping Thomas Kuhn’s theories alive and well.