Taking PCT for granted, Science or what?

[From Rick Marken (980306.2350)]

Me:

No. Remember, the controlled variable is affected _oppositely_ by
my statement _and_ your reply...See, it comes out the same.

Jeff Vancouver (980306.1615 EST) --

Not quite. Where is "being respected" located?

Ah. Good question. It exists as a perception in the brain of
the observer. This is really the difference between the terms
"controlled variable" and "controlled perception". "Controlled
variable" refers to the observer's _perception_ of the
perceptual variable that is being controlled by the actor.

"Controlled variable" _does not_ mean "real thing out there in
the world" and "controlled perception" doesn't mean "the actor's
perception of the controlled variable". It's ALL perception --
for both the actor _and_ the observer of the actor. A controlled
variable is just as much a perception as the perceptual variable
to which it (presumably) corresponds.

In our tracking tasks it may seem like the controlled variable is
the _real_ position of the cursor and that the controlled perception
is the actor's perception of that position. But the controlled
variable also exists only as a perception for the observer; the
controlled variable is often a different _kind_ of perception than
the perceptual variable to which it corresponds. In our experiments,
the controlled variable is the perception of a list of numbers in
the computer; these numbers presumably correspond to the perceptual
variable that the actor is actually controlling. The fit of our
models to behavior suggest that our perception of the controlled
variable corresponds _very closely_ to the perceptual variable
the actor is controlling.

The fact that a controlled variable is a perception is obvious when
you look carefully at the variables that people control. For
example, consider "making a fist". The "fist" seems like a real
thing out there but it is not; it the state of a visual perception
("degree of hand clench"?) that is an arbitrary function of an
arbitrary set of lower level input perceptions (of finger and hand
positions). The fist is a perception for an observer as much as it
is a perception for the actor, although the actor's perception of
"degree of hand clench" is likely to be based on different lower
level perceptions -- ie. kinesthetic _and_ (maybe) visual perceptions.

My point is that the term "controlled variable" (cv) represents the
_observer's_ perception of the perceptual variable (p) that the actor
is controlling. Both the cv and p are perceptual variables. When the
Test is successful, the aspect of the observer's perceptions that
has been identified as the cv should be nearly isomorphic to the
perceptual variable, p, that the actor is actually controlling.

My "you're insulting me" has no effect on my "level of respect
felt." This is because I am out-of-control on my CV.

Then "level of respect" is not a variable you are controlling.
Or you are simply not controlling it successfully. I personally
think you are controlling a variable that is more accurately
described as "my understanding of PCT". When I say "no" or
"you are wrong" it is a disturbance to your perception of how well
you understand PCT and you try to correct this perception by saying
that I am insulting you. You just don't want to hear Bill or me
contradict your claims about the relationship between PCT and
conventional psychology, for example. If your idea of being
respected is not having your views of PCT contradicted then I think
you really are going to have a tough time controlling for that
definition of "respect" on this net.

Me:

To understand how o cancels the effect of d on p you have to
understand how control systems work, not how o affects d!!

Jeff:

"Cancel out" does not mean "affect." Turning the car steering
wheel cancels the effect of the wind without actually pushing
the wind. I do not think you intend to insult me...I am insulted
... To me it shows a lack of respect. Had Bill said what I said
you would not have thought he meant what you thought I meant. T

Yes. If Bill had said what you said I would have said the same to him.
What you said was this:

But then what is the physical system that allows o to have an
impact on d? Since d and o are operating in the physical
environment, that is the laws that apply, correct?

There is no "physical system" of "laws" that allow o to have an
impact on d. This comment reflects a lack of understanding of what
a cv (or p) is. Suppose. for example that a person is controlling
for a triangular pattern in the "coin game". Disturbances to this
perception are certain movements of the coins; these disturbances
can be corrected by moving coins, adding coins, etc. Note that
there is no physical system that allows these outputs to have an
impact on the disturbance. The outputs (coin movements) have an
"impact" because they influence a controlled perception (the
triangular pattern of the coins) that exists only in the brain
of the actor (and of the observer, maybe, as a perception of the
controlled variable). There may be no direct physical impact at
all of the actor's coin movements (o) on the tester's coin
movements (d). Indeed, the only time the actor's movements (o)
physically affect the disturbance (d) is when the actor moves
one of the coins moved by the tester back into its original position.

Dick Robertson (980306.1825CDT) --

I wonder whether we haven't reached a point where Bill, Rick and
others ought to save some of your posts in a special file called,
"generic refutations," or the like, and when some, "same old issue"
crops up again, hit the reply button and hit Macro A, B, or C, etc.,
as applies and get on with it?

I don't think we'll ever reach that point. I think that the nice
thing about the net is that we can learn from these on-line
discussions (and I have learned a ton from them) in a way that
is impossible from books. I think the discussions on the net,
though often repetitive in overall substance, can address detailed
questions and concerns in a way that is impossible by just pointing
someone to "B:CP p. 34" or "LCS, p 56", etc. If some of the
discussions seem too detailed or repetitious then it's really not
that difficult to start another thread. If the new thread is
interesting to some people then it will continue. I think we tend
to discuss what people want to discuss. Actually, I think it's
interesting that the discussions so often return to the nitty
gritty basics of the natire of behavior and the nature of control;
I think that's really where the PCT revolution lives.

Anyway, I am really glad to see that your paper (with David) will be
published in the IJHMS issue that Martin is editing. I would like to
see a copy as soon as possible (maybe you could e-mail me an
electronic version?) because I think it's a good example of the
kind of applied type research I have been trying to describe
(offline) to Tim Carey and Susan Souter.

Best

Rick

ยทยทยท

--

Richard S. Marken Phone or Fax: 310 474-0313
Life Learning Associates e-mail: rmarken@earthlink.net
http://home.earthlink.net/~rmarken/

[From Bruce Gregory (980307.0649)]

Rick Marken (980306.2350)

Ah. Good question. It exists as a perception in the brain of
the observer. This is really the difference between the terms
"controlled variable" and "controlled perception". "Controlled
variable" refers to the observer's _perception_ of the
perceptual variable that is being controlled by the actor.

"Controlled variable" _does not_ mean "real thing out there in
the world" and "controlled perception" doesn't mean "the actor's
perception of the controlled variable". It's ALL perception --
for both the actor _and_ the observer of the actor. A controlled
variable is just as much a perception as the perceptual variable
to which it (presumably) corresponds.

Very nice post. This point is exactly the one I have been getting at
by talking about dwelling in different perceptual worlds.

Bruce

[From Bill Powers (980307.0708 MST)]

Rick Marken (980306.2350)--

JEFF:>> But then what is the physical system that allows o to have an

impact on d? Since d and o are operating in the physical
environment, that is the laws that apply, correct?

RICK:>There is no "physical system" of "laws" that allow o to have an

impact on d.

The problemn here is that you and Jeff are using "disturbance" differently.
Jeff is talking about something like Martin Taylor's "disturbance signal",
the effect that actually occurs. You are talking about d, the remote
variable that produces this effect.

Actually, Jeff is talking about the disturbance as "the effect that would
occur if the output did not cancel it." That's why "DS" is such an elusive
idea. It can't be observed directly, because it is opposed by the output.
All that can be observed directly is qi and Fe(o). Given the computed
effect of Fe(o), it is plain that qi is not what it should be if the output
were the only thing affecting it. The only way in which qi can be what it
is, given the observed influence of o, is for some other influence to be
acting oppositely to the effect of o. Suppose we observe that qi is 3,
while Fe(o) is +200. If Fe(o) is +200, then qi should be +200. Since qi is
observed to be 3, it is obvious that there must be some other influence
having an effect of -197 on qi, in the same units. That -197 is the
magnitude of DS. We don't observe any variable with a magnitude of -197; DS
isn't a real physical variable until we can find some physical way to
account for that -197 units of effect. That's why we talk about d and Fd in
PCT, instead of DS.

Best,

Bill P.