NetNews Usenet Archive 1993 #1/NN_1993_1.iso/spool/bit/listserv/csgl/2116

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Date:         Tue, 12 Jan 1993 13:19:00 GMT
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Subject:      Catching (not throwing) up
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From Greg Williams (930112)

Buried under two feet of white paper, rather than two feet of white H2O. Gary,
Koza's mammoth tome didn't help this situation. Pat's first comment was,
"Yeah, LISP -- it makes sense for this. Or assembly language (like in
TIERRA)." Mine: "Somebody's going to make a lot of bucks off this for a long
time." We're now thinking that some of the ideas will be helpful in writing
our "super" NSCK (with reorganization). I recommend, especially to Martin
Taylor and his colleagues, John R. Koza, GENETIC PROGRAMMING: ON THE
PROGRAMMING OF COMPUTERS BY MEANS OF NATURAL SELECTION, MIT Press, 1992. (And
also, by the way, Robert A.M. Gregson, TIMES SERIES IN PSYCHOLOGY, Erlbaum,
1983.)

Neat paper on adaptive control at sea, as discussed by the "Gang" and Bill
recently: Wim Velderhuyzen and Henk G. Stassen, "The Internal Model Concept:
An Application to Modeling Human Control of Large Ships," HUMAN FACTORS 19,
1977, 367-380. (Several papers in the same issue show highly predictive models
for driving a car, etc.)

-----

>Rick Marken (930110.1030)

>You seem to treat the writings of Skinner and other behaviorists as though
>they were religious texts.

Well, maybe the APOCRYPHA. A VERY loose canon!

>I personally don't much CARE what these people SAY; you can find a quote in
>Skinner to show that he knew all about PCT as easily as you can find a quote
>in genesis to show that the Biblical author (God?) knew all about evolution
>or quantum physics.

I wasn't claiming that behaviorists (or Skinner in particular, or nonPCTers in
general) "know all about PCT." I was claiming that it appears to me that some
PCTers have claimed that an "outputs-don't-alter-inputs" stance for these
folks which at least some of them do not actually evidence.

>So I'm not going to waste my time trying to find quotes in the
>scripture of conventional psychology (or life science in general)
>to support my claim that they believe in an output generation
>model of behavior. You can prove ME wrong about my claim by
>pointing to ONE -- just ONE -- study in conventional psychology
>that involves testing an organism to determine what perceptual
>variable it is controlling for; just one.

I wasn't claiming that nonPCTers generally disturb one organism to find out
what it is controlling for. I was claiming that what they DO generally do is
not always based on the idea that inputs can NEVER be affected by outputs.
Even my 10-year-old son is brighter than some PCTers have painted the
intelligence of the behaviorists; Evan knows that if there is a feedback
connection through the computer in a tracking experiment, then that condition
needs to be recognized. I claim that behaviorists actually realize that too.
The FACT of a feedback connection is accepted by them. They STILL can propose
an input-output model, which says that, at a given time t, H = f(C,T)
(including the possibility of derivatives and maybe integrals of C). They
would say that it is fine if the history of C is influenced by past values of
H.

-----

>Gary Cziko 930110.2106

>Perhaps we need to make a distinction between generative and explanatory.

>To explain we would have to move to an underlying level, from psychology to
>physiology, for instance.

>So perhaps a difference between behaviorism and PCT is that while both try
>to be generative, only PCT tries to be explanatory.  To make predictions we
>need a generative theory.  To answer "why" something happens, we need an
>explanatory one.

This is basically what I've been saying in trying to raise the question: are
PCT models of tracking (to date) really explanatory? Are there any underlying
variables (hypotheticals) in them, or just observables? The arm model
certainly includes hypotheticals, and is explanatory, as well as predictive.

>Where does this leave Newton?

Maybe the Bill Powers of his generation.

-----

>Bill Powers (930110.1900)

>Explaining how a music box works could go like this:

>1. Turn the key until it won't turn any more.
>2. Open the lid; this causes the music to play.
>3. To stop the music, close the lid.
>4. If the music stops by itself, return to step 1.
>5. The above explains how the music box makes music.

>Or like this:

>The key on the music box winds a spring. When the lid is opened,
>a catch is released and the spring turns a drum with little pins
>sticking out of it. The pins bend and release flat springs, each
>spring making a different sound. This explains what causes the
>music to play.

Exactly the point of my "radio" parable. Now, where does a model for tracking
which uses C,H, and T as its variables fit? And where does a model of
gravitational attraction which uses distance and mass (observationally
proportional to weight) fit? In what sense do these go beyond description?

-----

>Dennis Delprato (930111)

>Greg Williams (930109)

>And through which mechanisms does this history operate?  The
>operant theorist is forced to stay descriptive.  Fear of mysterious
>nonspatiotemporal inner processes leads them to posit no
>underlying process.  Admirable perhaps when all that was
>available was mysterious.  Wide open territory for PCT.

Exactly. And for all of "cognitive" psychology. Still, I think Skinner's
"prematurity" warning still counts for something, especially with regard to
postulating the details of HUMAN innards.

>The trouble may be that they stop with a description of the
>experimental set up (i.e., procedure).  They take the procedure
>(e.g., S dee-Response-Reinforcer, coupled with deprivation or
>the like) sufficient for explanation.  Incorporation of a
>control system account requires that one go beyond the obvious
>details of the procedure, including history of reinforcement and
>verbal statements that "feedback is involved."

Actually, from what I've read, they actually claim that they DON'T WANT TO
COME UP WITH AN EXPLANATION -- ONLY PREDICTION/CONTROL. But the upshot is as
you say, of course, and they can't get as close to their professed goal as
they could with PCT models (which, as noted yet again above, might be very
difficult to generate for complex situations).

>Seeing the whole loop, with BOTH environmental and organismic influences on
>output, is EXACTLY the middle way between environmentalism and organismism
>which I was arguing for some time back.

>Bill is right.  Skinner always came back to the environment as the ultimate
>independent variable.  Although he and many followers have verbally stated
>that environment determines response and response determines environment
>(stimulus), in practice, this has amounted to nothing.  True, some followers
>(e.g., Baum) have gone a bit farther than did Skinner, but Bill can tell us
>about these.

Maybe I was unclear. Skinner's extreme historical environmentalism and an
extreme "moment-by-moment" mechanistic organismism need melding into a broader
-- and I think truer -- picture. I was agreeing with Bill that Skinner was an
environmental determinist. PCT provides the basis for the truer picture: both
the perceptual inputs (fed-back "inputs," reflecting environmental
disturbances) and the reference signals (resulting from the organism's history
and genetics) COMBINE to produce outputs at any time.

>Some behavior analysts are getting away from stimulus as true
>independent variable and response as true dependent variable.
>BUT, as with above comment, they do not go anywhere with this
>thinking.  Close but so far.

P. Meehl in a recent PSYCHOLOGICAL REPORTS has a very sophisticated article
about Skinner's original bowing and later recantation of state (internal
variables. Indeed, some behaviorists are beginning to consider the effects of
manipulating deprivation.

>In my opinion, the major stumbling block for behavior analysts
>as far as PCT is the requirement to take S-R and R-S as
>SIMULTANEOUS.  This is very difficult for two basic reasons:
>(1) our culture teaches lineal thinking and (2) the damn
>procedure (itself a product of lineal biases) is lineal
>(ess D then R then reinforcer).  The only way to get S-R
>and R-S simultaneous is via theory, then this poses the added
>difficulty of changing the status of the response consequence.

How true.

>Hope I've said something to help Greg.  My perspective suggests
>there is a great opportunity for one to prepare an interesting
>paper entitled something like "From Feedback Functions to
>Perceptual Control Systems."

I value your comments. I suspect that we better not hold our breath until
someone writes that paper. My perception is that here in the "PCT ghetto" (as
Tom Bourbon has put it), most have already come to the conclusion: why bother
trying to convince the affluent folks uptown of ANYTHING? When the revolution
comes, we'll show THEM!

As ever,

Greg