Lest there be error

CSGnet Archive CSG2003
1

[From Fred Nickols (2002.03.05.0642)] --

Bruce Nevin (2003.03.04 22:11 EST)]

Bruce Gregory (2003.0304.2125)--

Bruce Nevin (2003.03.04 15:49 EST

Bill Powers (2003.03.04.0332 MST)--

The hypothesis we will be testing immediately is that stress leads to
reorganization which is detectable as _dis_organization of a previously
skilled performance.

An alternative hypothesis that you must distinguish somehow is that a
degradation of performance is due to distraction. How do you know that the
freezing foot or whatever is not simply distracting the subject from
attending fully to the task?

What is a distraction? It seems to me that it might be a reaction to an
error in a loop controlling a variable other than the variable of interest.

In this case, yes. Another form of distraction is control without error
that demands attention (lest there be error). This can be control with high
gain, or could be control that engages some of the means of control
(eyesight, hands, left foot, whatever) so that they are not available as
means for controlling the variable from which you are distracted.

"Lest there be error." That implies to me that we act not just to keep
perceptions at or near the reference signal, sometimes in response to
disturbances, but also to predicted disturbances as well. Thus, a zero
error signal might not result in no action. OR -- and that's a big or --
any given CV might exist nested in an array of related CVs, some of which
have to do with preventing disturbances (i.e., maintaining the conditions
that make controlling the primary CV of interest a feasible
undertaking). As you can see, I'm not sure I understand "lest there be
error." Could you and others say more about it?

The notion of distraction is related to attention. It might be useful to
think about how ignoring is done. Some control requires concentration. You
concentrate by ignoring everything else. A distraction is something you are
unable to ignore. That encompasses both types noted above.

It would seem to me that a "distraction" (i.e., something you are unable to
ignore) is some other CV that has gotten out of kilter and demands
attention as well.

By the way, I'm assuming that any zero difference between a perception of a
CV and the reference signal for that CV needn't actually be true zero but,
like in the old fashioned circuits on which I used to work, can be of some
value ( + or - ) as long as it is within some tolerance ( + or - ).

Anyway, please say some more about "lest there be error."

Fred Nickols
nickols@safe-t.net
www.nickols.us

···

At 09:27 PM 3/4/2003, Bruce Gregory wrote:

At 07:06 AM 3/4/2003, Bill Powers wrote:

2

from [Marc Abrams (2003.03.05.0723)]

[From Fred Nickols (2002.03.05.0642)] --

>Bruce Gregory (2003.0304.2125)--

>>Bruce Nevin (2003.03.04 15:49 EST

>>>Bill Powers (2003.03.04.0332 MST)--

>>>
>>>>The hypothesis we will be testing immediately is that stress leads to
>>>>reorganization which is detectable as _dis_organization of a

previously

>>>>skilled performance.
>>>
>>>An alternative hypothesis that you must distinguish somehow is that a
>>>degradation of performance is due to distraction. How do you know that

the

>>>freezing foot or whatever is not simply distracting the subject from
>>>attending fully to the task?
>>
>>What is a distraction? It seems to me that it might be a reaction to an
>>error in a loop controlling a variable other than the variable of

interest.

>
>In this case, yes. Another form of distraction is control without error
>that demands attention (lest there be error). This can be control with

high

>gain, or could be control that engages some of the means of control
>(eyesight, hands, left foot, whatever) so that they are not available as
>means for controlling the variable from which you are distracted.

"Lest there be error." That implies to me that we act not just to keep
perceptions at or near the reference signal, sometimes in response to
disturbances, but also to predicted disturbances as well. Thus, a zero
error signal might not result in no action. OR -- and that's a big or --
any given CV might exist nested in an array of related CVs, some of which
have to do with preventing disturbances (i.e., maintaining the conditions
that make controlling the primary CV of interest a feasible
undertaking). As you can see, I'm not sure I understand "lest there be
error." Could you and others say more about it?

Fred, I'm certainly not trying to answer for Bruce, he will clarify his
intent. But I would like to give my take on this. I believe and hypothesize
that we have a hierarchy of CV's and in conjunction with that a hierarchy of
arousal ( was anxiety ) What we pay attention to is tied to what CV's are
aroused at the time. A distraction could be , as you suggest, simply a
another CV that has taken priority ( if only temporarily ) from another CV.
You could also call a distraction a disturbance to a CV. This also seems to
make sense, because when a variable is disturbed and goes around the loop an
error could occcur and arousal take place. I agree with your "nested"
concept. You could call them supporting CV's. They are no different ( have
the same properties ) from any other CV, Just a way of practically dealing
with them.

Marc

3

[From Bill Powers (2003.03.05.0734 MST)]

Fred Nickols (2002.03.05.0642) --

>"Lest there be error." That implies to me that we act not just to keep
>perceptions at or near the reference signal, sometimes in response to?\
>disturbances, but also to predicted disturbances as well. ...l I'm not
sure I >understand "lest there be error." Could you and others say more
about it?

Thanks, Fred.I hate to be the one who's always carping about dubious
concepts from outside PCT.

The only situation I can see in which there might be an advantage in acting
prior to the occurrance of error is the one in which there must be some
preparation prior to the actual movement to correct error. An example is a
catcher holding his mitt up in the general region where the ball is
expected to arrive. This preparatory action reduces the distance over which
the mitt will have to move when the ball is actually thrown, and possibly
saves a very small fraction of a second that may or may not make any
difference. The probability of moving the mitt rapidly in the right
direction prior to the delivery of the ball is practically zero, so the
catcher simply has to wait to see where the mitt is relative to the
projected path of the ball, and let the error produce the motion..

As to actually producing an error-correcting action when the error is zero,
I think that this proposition needs some work. Suppose you're driving a
car, maintaining a constant speed, and you see a rise in the road
approaching. Should you press down on the accelerator? What will happen if
you do? Won't you create a speed error?

There are some small gains to be had from "feed-forward," but they are
greatly exaggerated by those who want to make this phenomenon a significant
part of control behavior.

Best,

Bill P.

4

[From Bill Powers (2003.03.05.0748 MST)]

[Marc Abrams (2003.03.05.0723)]--

>Fred, I'm certainly not trying to answer for Bruce, he will clarify his
>intent. But I would like to give my take on this. I believe and hypothesize
>that we have a hierarchy of CV's and in conjunction with that a hierarchy

arousal

>(was anxiety )

Hey, all you guys, what's going on here? Anxiety? Arousal? For that matter,
Stress? What theory are these words from? Is there any reason to think that
these words have any usable definitions at all? If they had any real
definitions I'd be happy to consider them, but as far as I know they're
just vague noises people make when they're trying to indicate that
something has gone wrong. Please correct me if that's a stupidly wrong
impression that I have. I don't mind starting from such terminology, but
the first job we have is to figure out what they refer to, if anything,
that can be represented in a working control-system model. We can do
research on evidence of reorganization that shows up when errors are
induced in various control systems, because those terms have experimental
meaning. We can't do research on anxiety, arousal, or stress (and when you
come right down to it, neither can anyone else).

>What we pay attention to is tied to what CV's are aroused at the time.

What? Suppose the controlled variable happens to be the amount of salary I
make. How does the amount of salary I make get aroused? How is it different
from when it's just lying there?

>A distraction could be , as you suggest, simply a another CV that has
taken priority >(if only temporarily ) from another CV.

Can a CV do that? In fact, can a CV do anything by itself? I thought the
brain selected perceptions to control, set reference levels for them, and
acted to bring them to the selected reference levels. The CVs are the
externally visible variables that (the observer assumes) are being
perceived and controlled. Aren't they? Are you offering a new theory here?

>You could also call a distraction a disturbance to a CV. This also seems to
>make sense, because when a variable is disturbed and goes around the loop an
>error could occcur and arousal take place.

Now CVs can go around the loop? How the heck do they do that? I thought
they were variables we observe in the environment which seem to be under
control by some organism (or other device).

Are you guys tired of PCT? If so, just say so and I'll stop bugging you
like this. If you're serious about PCT, then let's stick to PCT.

Best,

Bill P.

5

from [ Marc Abrams (2003.03.03.1040) ]

[From Bill Powers (2003.03.05.0748 MST)]

Hey, all you guys, what's going on here? Anxiety? Arousal? For that

matter,

Stress? What theory are these words from?

Bill, it's my contention that PCT error is in fact Stress, or what people
commonly refer to as Stress. Error is defined in the Oxford Dictionary as an
action of wandering or roaming. I believe that wandering or roaming is
caused by an arousal of some type from an electrical signal or chemical
reaction. I believe that is what takes place when the comparator "compares"
the goal to the state of the variable. Am I wrong in these beliefs?I didn't
want to use the word anxiety because it had a negative conotation only, and
arousal seemed to fit. I guess "excited" could also be used.

Is there any reason to think that these words have any usable definitions

at all?

Maybe not for us, but you better be able to talk in terms that others can
understand. I'm all for accurate and precise terminology. I know that
existing words and more precisely, word definitions, do not lend themselves
to the PCT model. Inventing new meanings is not the answer. So we got to go
with what's out there. It's a problem.

If they had any real
definitions I'd be happy to consider them, but as far as I know they're
just vague noises people make when they're trying to indicate that
something has gone wrong.

Is this your definition of error? If so, I don't think it's a useful one to
communicate that idea.

Please correct me if that's a stupidly wrong
impression that I have. I don't mind starting from such terminology, but
the first job we have is to figure out what they refer to, if anything,
that can be represented in a working control-system model.

I agree. That's the purpose of the research

We can do
research on evidence of reorganization that shows up when errors are
induced in various control systems, because those terms have experimental
meaning. We can't do research on anxiety, arousal, or stress (and when you
come right down to it, neither can anyone else).

I don't understand. Are you now saying that the DSR or Heart Variabilty
Meter _cannot_ be used as correlates for "measuring" changes in CV's,
"learning" or for "Stress". I know these obviously are not and cannot be
direct measurements of these phenomenon, so what in fact _is_ being
measured?

What? Suppose the controlled variable happens to be the amount of salary I
make. How does the amount of salary I make get aroused? How is it

different

from when it's just lying there?

Exactly how do you control for the amount of salary you make. The definition
of arousal is to stir up, to excite. If some error occured to that variable,
such as, having your salary docked or garnished, or a raise, would possibly
indicate either a change in CV's or lesser or higher gain in them.

>A distraction could be , as you suggest, simply a another CV that has
taken priority >(if only temporarily ) from another CV.

Can a CV do that? In fact, can a CV do anything by itself? I thought the
brain selected perceptions to control, set reference levels for them, and
acted to bring them to the selected reference levels. The CVs are the
externally visible variables that (the observer assumes) are being
perceived and controlled. Aren't they? Are you offering a new theory here?

No, I simply used shorthand, instead of indicating the whole control loop

>You could also call a distraction a disturbance to a CV. This also seems

to

>make sense, because when a variable is disturbed and goes around the

loop an

>error could occcur and arousal take place.

Now CVs can go around the loop? How the heck do they do that? I thought
they were variables we observe in the environment which seem to be under
control by some organism (or other device).

Sorry, I meant variables.

Are you guys tired of PCT? If so, just say so and I'll stop bugging you
like this. If you're serious about PCT, then let's stick to PCT.

Take a deep breath. :slight_smile: We are all with you.

Marc

6

[From Bruce Nevin (2003.03.05 13:15 EST)]

Fred Nickols (2002.03.05.0642)–

Bruce Nevin (2003.03.04 22:11 EST)]

Another form of distraction is control without
error

that demands attention (lest there be error).

“Lest there be error.” That implies to me that we act not
just to keep

perceptions at or near the reference signal, sometimes in response
to

disturbances, but also to predicted disturbances as well. […] I’m
not sure I understand “lest there be error.” Could you
and others say more about it?

Bill Powers (2003.03.05.0734 MST) –

Thanks, Fred.I hate to be the one who’s always
carping about dubious

concepts from outside PCT.

Not a “concept from outside of PCT”, merely hasty and off-hand
language. Sorry. Not controlling my writing with high enough gain
(“hasty” & “careless”) because completing the
reply was an interruption to an entirely separate sequence I was
controlling.
When my attention wanders, there is error, so I concentrate on the CV.
This is not in anticipation of error, it is merely ongoing control with
gain high enough to prevent error.
“Concentrate”: what this seems to mean is that I
“ignore” other CVs that are ‘close enough’ to their reference
values, that is, don’t produce any control actions directed at them,
including “attentive” observation actions such as looking at
them, listening to them - selecting their sounds out of the complex of
audio input - etc.
Then the value of some other CV diverges from its reference value. It
appears that this error “attracts” my attention.
“Attract attention”: What this seems to mean is that I begin
control outputs to reduce the error, and the means of control (eyes,
hands, etc.) can only (or only easily) be used on one of the CVs at a
time.
This is what makes the second CV a “distraction” from
controlling the first.
Consequently, at the time of “distraction” there is no error in
control of the first CV, but after I have been “distracted”
there is error.
There are other forms of “distraction”. Suppose I’m a child
obligated to do something but don’t really want to. My attention
“wanders” from the task because I’m not “really
motivated”. One might guess that there is a control system that
scans the environment for something “of interest”, but more
simply the loop gain for controlling the CV drops low enough that error
in one of many other always concurrent control systems becomes a stronger
“candidate for attention”. (I’m using these words loosely
because I don’t know what the mechanism is for error “attracting
attention”.) Completing a sequence, say, has high gain as means of
controlling the obligation, but I control the current step with low gain
(I don’t want to do it, I just want it to be done) and
consequently am distracted when the gain drops below that for - what’s
that buzzing sound? Oh, look at that fly by the window. I wonder if I
could catch it.

The notion of
distraction is related to attention. It might be useful to

think about how ignoring is done. Some control requires concentration.
You

concentrate by ignoring everything else. A distraction is something you
are

unable to ignore. That encompasses both types noted
above.

It would seem to me that a “distraction” (i.e., something you
are unable to

ignore) is some other CV that has gotten out of kilter and demands

attention as well.

I agree. See above.

By the way, I’m assuming that any zero
difference between a perception of a

CV and the reference signal for that CV needn’t actually be true zero
but,

like in the old fashioned circuits on which I used to work, can be of
some

value ( + or - ) as long as it is within some tolerance ( + or -
).

I agree. See above.

    /Bruce

Nevin

···

At 06:44 AM 3/5/2003, Fred Nickols wrote:

7

[From Bill Powers (2003.03.05.1404 MST)]

Bruce Nevin (2003.03.05 13:15 EST)--

Not a "concept from outside of PCT", merely hasty and off-hand language.
Sorry. Not controlling my writing with high enough gain ("hasty" &
"careless") because completing the reply was an interruption to an
entirely separate sequence I was controlling.

Etc.

I can see that my viewpoint is not particularly appreciated. I will stop
being annoying, Marc, have you received the attachment yet? I'm working on
the writeup, but not very fast.

Best,

Bill P.

8

[From Bruce Nevin (2003.03.05 23:26 EST)]

Bill Powers (2003.03.05.1404 MST)--

···

At 04:08 PM 3/5/2003, Bill Powers wrote:

I can see that my viewpoint is not particularly appreciated. I will stop
being annoying

Huh? Is someone annoyed? Sorry to be dense, but I don't understand what you're saying.

         /Bruce Nevin