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orthonormal comments on The usefulness of correlations - Less Wrong
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I'll give this one last try.
You've given me the two results I mentioned above, in the area of motor response. They sound like good experiments to me: you can take a model with relatively few free parameters, and find that most subjects' behavior will fit that model extremely well for some particular values of the parameters. That is the kind of experiment I'd take as good evidence that control theory operates in motor response. (Incidentally, if you could give me a link to those experiments, I'd much appreciate it.)
You've been claiming for months that this is just the tip of the iceberg, that PCT is able to isolate variables that subjects are controlling in cognitive contexts like belief. I would be very interested in this claim if I saw some evidence for it; fortunately, your claim that PCT is able to diagnose and treat cognitive conditions implies that it's strong enough to do the same kind of experiments as in the case of motor response. So I began by asking for references to such results, and gave an example of the kind of result that would definitely move me to look into PCT.
Experimental verification seems to me like the obvious thing for PCT advocates to do if they're confident in their theory and frustrated by its lack of academic respect. I would therefore find it highly unlikely, given that your claims are true, that in 35 years there hasn't been a single positive experimental result in a cognitive context, of the same form as the "controlling the position of the dot" or "varying the force on the bar" experiments. That you meet my question with outrage, rather than with citations, is thus Bayesian evidence against the validity of PCT.
Nope. I'm just claiming that if PCT doesn't have the kind of evidence it claims, then I probably shouldn't bother investigating it. The problems with mainstream psychology are manifold, but the discipline seems to be making (slow) progress by scientific criteria: Tversky and Kahneman, for instance, were making novel and unexpected experimental predictions that turned out to be correct. If your discipline does that much better than mainstream psychology, there should be some strong experimental results that show it.
I really can't imagine that's too much to ask, and that's why I've made this challenge. Point me to experimental results that validate PCT in a cognitive context, and I'll pick up the textbook of your choice. Keep grandstanding against the very kind of evidence you presented as evidence of PCT in motor response, and I'll have to conclude that you're peddling woo-woo. The ball is in your court.
I take it you skipped reading Marken's references then, since I believe one of the cited papers was on how physicians' errors in prescribing medicine match a PCT model of the situation, but fail to match an intuitive model of how such errors would respond to environmental changes.
You've apparently also been ignoring my repeated mention of time-averaged perceptual variables like "the amount of work I've done today" or "how recently I got laid" - you can have a "feel" for such values, and how they change over time, as well as respond to changes in them. Do you claim to not perceive -- and control -- such variables? Or are you going to say that since "work" and "getting laid" involve physical activity, they are somehow therefore "motor" rather than "cognitive"?
Finally, you seem to have put me in the strange position of a passing physics student being harangued by a young earth creationist, insisting that I prove the age of the universe to your satisfaction, before you will study any physics, whereas I assert that if you were to go and study some physics, it will be obvious to you why YEC-ism is wrong.
But after being harangued at some length, I relent and attempt to begin with some basic equations, which you then argue are not in the Bible and thus not valid evidence. It is at this point, I begin to question who you're trying to convince by your diatribe, and why, if you genuinely want to learn something, why you're spending more time writing than reading. Don't you have a library anywhere near you?
I'm not sure I follow you here, since I've only referred to neuroanatomy evidence -- i.e. evidence from a "hard" science. You may be confusing me with one of the other PCTers here who've been talking about the joystick perception experiments, which I consider only relevant for debunking Skinner... which isn't really as useful as it used to be.
OK, that does sound like a result of the type I'm looking for. I think I can find "Error in skilled performance" at my campus library. In the meantime, could you tell me if the following are true in your opinion:
Thanks.
I would guess Marken is respected; I have not read the paper, only his brief mention of the results in a talk he gave summarizing his 25 years of PCT-related research. I have no idea whether you would consider it "strong evidence". However, here is a portion of that synopsis:
Sorry, but that doesn't sound like an interesting result that vindicates PCT. You can even rephrase the general insight without controls terminology!
Like this: "given a system that is demonstrably robust against failure mode X, it's unlikely to fail in mode X".
Positing a "control system" is just unnecessary length and unnecessary delimitation of the general rule. PCT doesn't get you this insight any faster. And while human factors engineers would discourage similarly named, very different drugs, even they would admit it might not be worth fixing if the system has already operated without ever swapping out the drugs.
OK. Well, I've read the paper now, and I find that I strongly disagree with a key component of Marken's methodology, and that I think this zeroes in on the cause of our argument here about what kind of experimental evidence counts for PCT. Frankly, though, I don't want to spend time arguing against it only for you to say "OK, maybe Marken is a crank, but that doesn't say anything against other PCT researchers". So if it's not too much trouble, could I ask you to read the (short) paper and tell me:
If the answer to either of these questions is "No", then we're just back where we started, with me asking for experimental evidence for PCT in a cognitive context. If the answer to both is "Yes", then I think I can explain my disagreement.
If Marken will turn out to be both a crank and a respected member of PCT community, it will say something about the community.
ETA: Technical report "Error in Skilled Performance: A Control Model of Prescription Writing" (2002) can be found online here.
Thanks for your efforts at an even-handed attempt at seeing if PCT meets vital reality checks.
If it's not too much trouble, would you mind answering even ONE of the many, many points and questions I've brought up in this thread? I mean, as long as we're not trusting each other, I frankly don't trust you not to change your criteria on the fly, either.
For example, you've still not defined what your criteria for what you'd consider a "novel" result, nor which "standard model" you would use as a baseline for comparison. Nor have you addressed the issue of any of the many cognitive variables that are available for your direct observation, nor what your criteria are for what you'd deem "cognitive" vs. "motor".
These are all areas where you are quite free to change your stance at will, and I do not wish to waste any more of my time, if your true goal here is simply to find an excuse (at any cost) to not learn something. I want to make sure that you've stated your true objection first.
Fair enough.
It's hard to define explicitly what I'd consider a novel or surprising result, because— as you point out— mainstream psychology doesn't appear to have a unified reductionistic model of cognition, just an array of identified results and sub-models. I've thus made that requirement more charitable, changing it from "something novel or surprising" to the lower standard of "good modeling by control theory of a cognitive phenomenon", excluding motor response and some games (like a fielder catching a fly ball) in which acting externally like a simple control system is an easy and successful strategy.
By "motor response" I mean just the way that the actual nerves and muscles can vary their particular actions, while not changing the conscious description of what I'm doing. For example, I assign significant probability that a simple control circuit can be found that neatly fits the actions of my leg muscles (or the nerve signals that connect to them) when I'm walking and keeping my balance. I would, however, find it much less probable that a similarly simple control circuit fits my pattern of working vs. procrastinating. (Since control circuits are apparently Turing-complete, of course there's going to be some control circuit that matches it, but in the case of balance I think there's probably one with few enough parameters that it compresses the data effectively, compared to other models; while in the case of akrasia I doubt this.)
So I would count work vs. procrastination, or prescription errors, or charitable donations, or changing beliefs, as just a few examples of cognitive phenomena. Something like variation in libido over time, though, wouldn't surprise me as much if I find a control circuit model for it (though it would surprise me more than the balance example). I think it's fair to ask PCT for experimental evidence in the cognitive domain, since the way you diagnose and prescribe around here seems to presuppose some rather simple control circuits in cognitive phenomena.
As for considering direct introspection rather than experimental evidence, I'm rather mistrustful of what I consciously intuit about my own mind, since conscious awareness seems to be often distorted for signaling purposes, and since the false perception of religious experience (which I really wanted to be genuine) was one thing that kept me religious longer than I should have been. At this point, I strongly prefer experimental evidence.
With that said, could you read Marken's paper and tell me whether you stand behind it in the terms I asked above?
Now that I've read it, I have to say I agree with you: it is not good evidence. At best, it's an application of PCT to generate an interesting hypothesis or two.
I'm not sure why you'd expect akrasia to be a simple circuit. If it were a simple conflict, between exactly two things, you'd likely be able to resolve it consciously without much effort. A few weeks ago, I did a workshop where we charted a portion of one person's control structure in the area of not working on the iPhone app they wanted to write. It took a couple hours and filled most of a page with the relevant cognitive-level variables and their interconnections.
This is quite consistent with e.g. Ainslie's model of akrasia as involving multiple competing "interests"; I see PCT as an improvement over Ainslie in providing a straightforward implementation mapping, plus simplified management of Ainslie's notion of "appetites", which is not very well worked out (IMO) and a little too handwavy.
Replacing Ainslie's idea of "interests" having "appetites" with controllers measuring time-averaged variables seems like a straightforward win: instead of two entities, you have just one entity that's structurally similar to things we know our brains/nervous systems already have. (Also, Ainslie has no worked-out model for how prioritization and agreement between interests occur; PCT on the other hand has hierarchy and reference levels to account for them.)
Individually, the circuits are simple; collectively, the networks are not. I used to think things were simpler than they are, because I focused only on the things (functional beliefs) that were effectively connections between control circuits. I rarely addressed the settings of the circuits themselves, or used them as a springboard to identifying other beliefs or variables.
There's a difference between having a false label applied to a true experience, and having a false experience. The existence of perceptions such as "how much work I've gotten done lately" or "how much fun I'm having" is certainly some evidence for PCT's notion of time-averaged perceptual variables that can influence decision-making. It's also parsimonious to assume that the brain is unlikely to have evolved specific circuits for these perceptions, rather than simply having a basis for acquiring new perceptions.
In effect, the PCT model of cognitive variables explains how we represent all the things we "just know" or "just feel", including expert intuition in specialized subjects. The PCT prediction would be that if someone is skilled enough in a subject to have a specific intuition about something, we should be able to find a specific neural signal whose intensity corresponds to the degree of that intuition, and which is a time-averaged function of other (possibly gated) input signals.
I don't see how any of this seems extraordinary or controversial in the slightest, on the perception side.
Control, perhaps, might be more controversial... especially given the implication that we don't control our own actions directly, but can only do so through interaction with the control network. But for me, that implication is uncontroversial, because I've been writing about that (independently formed) idea since 2005.
Powers hypothesizes that "awareness" simply is a debugger that can go in and inspect any part of the network, injecting settings or testing hypotheticals. Anything we do by direct conscious intention would therefore consist of "manually" setting control values in the network, which of course would have no long-term effect if a higher-level controller puts the settings right back when you're done. What's more, if your conscious meddling is interfering with something in an "important" (high) position in the network, it's likely to reorganize in such a way that you no longer want to meddle with the network in that particular way!
And that actually sounds like the most straightforward explanation of akrasic behaviors, ever, and is also 100% consistent with everything I've already previously observed about mind hacking.
That is, we really don't control our own behaviors: our networks do. Free will is really just a special case, even if it doesn't seem that way at first glance. PCT just offers a better explanation than my rough models had for why/how that works.
Good. The experiment is, however, very good evidence for the hypothesis that R.S. Marken is a crank, and explains the quote from his farewell speech that didn't make sense to me before:
The basic problem is that, generically, if your model uses more free parameters than data points, then it is mathematically trivial that you can get an exact fit to your data set, regardless of what the data are: thus you've provided exactly zero Bayesian evidence that your model fits this particular phenomenon.
(This is precisely the case in the paper you pointed me to. Marken asserts that his model successfully predicts the overall and relative error rates with high precision; but if these rates had been replaced with arbitrary numbers before being fed to him, he would have come up with different experimental values of the parameters, and claimed that his model exactly predicted the new error rates! This is known around here as an example of a fake explanation.)
The fact that Marken was repeatedly told this, interpreted it to mean that others were jealous of his precision, and continued to produce experimental "results" of the same sort along with bold claims of their predictive power, makes him a crank.
Anyhow...
The point I keep stressing is that, if cognitive-domain PCT is precise enough to do treatment with, then it can't be bereft of experimental consequences; and no matter how appealing certain aspects of it might be intuitively, a lack of experimental support after 35 years looks pretty damning. If every cognitive circuit is so complicated that you can't make an observable prediction (about an individual in varying circumstances, or different people in the same circumstances, etc) without assuming more parameters than data points... then PCT doesn't actually teach you anything about cognition, any more than the physicists who ascribed fire and respiration to phlogiston actually learned anything from their theory.
You've pointed me to one experiment, which turned out to be the work of a crank; I've accordingly lowered the probability that PCT is valid in the cognitive domain, not because the existence of a crank proves anything against their hypothesis, but because that was the most salient experimental result that you could point to!
I'm still quite able to revise my probability estimate upwards if presented with a legitimate experimental result, but at the moment PCT is down in the "don't waste your time and risk your rationality" bin of fringe theories.
I'm not sure I follow you. I didn't get the impression that Marken's model had more tunable parameters than there were data points under study, or that it actually was tunable in such a way as to create any desired result.
I don't follow how this is the case. If I establish that a person is controlling for, say, "having a social life", and I know that one of the sub-controlled perceptions is "being on Twitter", then I can predict that if I interfere with their twitter usage they'll try to compensate in some way. I can also observe whether a person's behavior matches their expressed priorities -- i.e., akrasia -- and attempt to directly identify the variables they're controlling.
If at this point, you say that this is "obvious" and not supportive of PCT, then I must admit I'm still baffled as to what sort of result we should expect to be supportive of PCT.
For example, let's consider various results that (ISTM) were anticipated to some extent by PCT. Dunning-Kruger says that people who aren't good at something don't know whether they're doing it well. PCT said - many years earlier, AFAICT - that the ability to perceive a quality must inevitably precede the ability to consistently control that quality.
Which directly implies that "people who are good at something must have good perception of that thing", and "people who are poor at perceiving something will have poor performance at it."
That's not quite D-K, of course, but it's pretty good for a couple decades ahead of them. It also pretty directly implies that people who are the best at something are more likely to be aware of their errors than anyone else - a pretty observable phenomenon among high performers in almost any field.
This baffles me, since AFAICT you previously agreed that it appears valid for "motor" functions, as opposed to "cognitive" ones.
I consider this boundary to be essentially meaningless myself, btw, since I find it almost impossible to think without some kind of "motor" movement taking place, even if it's just my eyes flitting around, but more often, my hands and voice as well, even if it's under my breath.
It's also not evolutionarily sane to assume some sort of hard distinction between "cognitive" and "motor" activity, since the former had to evolve from some form of the latter.
In any event, the nice thing about PCT is that it is the most falsifiable psychological model imaginable, since we will sooner or later get hard results from neurobiology to confirm its truth or falsehood at successively higher levels of abstraction. As has previously been pointed out here, neuroscience has already uncovered four or five of PCT's expected 9-12 hardware-distinctive controller levels. (I don't know how many of these were known about at the time of PCT's formulation, alas.)