# UEC/NEC summary

**URL:** <http://discourse.iapct.org/t/uec-nec-summary/11863>\
**Category:** CSG2002\
**Created:** [May 28, 2002, 1:30pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863 "2002-05-28T13:30:04Z")\
**Posts on this page:** 19\
**Page:** 1

<div class="post-metadata">

**Author:** ![Stephen\_O\_Shaughness](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/s/df705f/32.png) [@Stephen\_O\_Shaughness](http://discourse.iapct.org/u/Stephen_O_Shaughness)\
**Post date:** [May 28, 2002, 1:30pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/1 "2002-05-28T13:30:04Z")

</div>

As someone who spends time in the woods following trails with choice points,  
on the way to a goal, I think I speed up as I gain confidence that I'm  
making the right choices. That's obviously not a smooth gradient, but I  
doubt if the measurement of the rats was that fine.  
David Wolsk

This reminds me of this weekends Indy 500.

Race teams are given a finite amount of fuel. If they race, flat out, for  
500 miles they won't make it. This years winner probably didn't have enough  
fuel to finish the race and was being passed by #2 when a yellow flag caused  
all drivers to slow down (conserving fuel) and hold their positions. Thus  
#1 was able to finish the race (and win)

#2 was increasing his speed (much like the rat) because he had the resources  
to accomplish his goal and his goal was in sight. Unfortunately the rules  
of the game forced him back into second place position.

It seems to me the further a rat (race driver or any other organism) is from  
the goal the more they are conserving and strategizing. The closer the goal  
the more resources can be diverted to achieving it. The rat/gradient  
example may be moot now, but there are still some points worth  
acknowledging.

Do we assume the rat, at the start of the maze, knows there is food at the  
end? It could be the rat is always in a search mode for food. This  
expends a lot of energy literally going in circles. As a given direction  
becomes more promising (closer to the goal) the rat can expend more energy  
or at least direct more energy in a given direction. Maybe the gradient  
observation is really a change in strategies. The rat shifting from search  
mode to acquire mode.

The strategies used near the start of the Indy 500 are not the same ones  
used at the end of the race. Rules of the game, track conditions, yellow  
flags, and quality/quantity of pit stops all change the dynamics of the  
race.

Can we set up a simple experiment with a dog on a leash? A spring scale (or  
if anyone has access to a strain gage and computer to log the pull) attached  
to the leash. I would move a food dish closer to the dog rather than have  
the dog move to the dish. In any case, with the dish several feet from the  
dog I think she is going to be in a different mode. She is going to be  
looking at the dish and the experimenters and wondering what tricks she is  
going to have to perform in order to be rewarded. With a food dish inches  
from her nose she is going to be in an acquire or eating mode. The human  
handlers are out of her field of view. Surely she has learned that food  
next to her nose is for eating and nothing else. Thus she will expend a  
large amount of energy in pulling towards what appears to be a sure thing.  
Is the gradient smooth or are there transitions?

Steve O

> **···**
>
> -----Original Message-----  
> From: David Wolsk [[mailto:davidwolsk@SHAW.CA](mailto:davidwolsk@SHAW.CA)]  
> Sent: Friday, May 24, 2002 1:38 PM  
> To: CSGNET@listserv.uiuc.edu  
> Subject: Re: UEC/NEC summary

---

<div class="post-metadata">

**Author:** ![bnhpct](http://discourse.iapct.org/user_avatar/discourse.iapct.org/bnhpct/32/34_2.png) [@bnhpct](http://discourse.iapct.org/u/bnhpct)\
**Post date:** [May 22, 2002, 11:34pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/2 "2002-05-22T23:34:48Z")

</div>

[From Bruce Nevin (2002.05.22 15:11 EDT]  
The UEC or NEC (I thought that was a Japanese computer company) is a  
proposed mechanism to account for the phenomenon of ‘giving up’, reducing  
gain when maximum gain does not reduce error, and conversely a mechanism  
that is proposed to increase gain as error diminishes.  
First we need clear instances of the phenomenon.  
Buridan’s ass and the pill bug are not instances for reasons  
discussed.  
The ill-mannered horse bolting for the barn to be fed is I believe not an  
instance for reasons that I described: I believe the horse is controlling  
a sequence perception, the last step of which is getting fed. There is  
lots of at least anecdotal evidence for controlling the pace of the steps  
of a sequence, performing them rapidly if the last step is desired or  
slowly if it is being avoided. I am not aware of any modelling of this.  
In fact, I’m not aware of any modelling of varieties of sequence control.  
I believe this would be a fruitful place to look.  
I think maybe arm wrestling was mentioned as an example in an earlier  
spate of UEC discussion. The idea was that a person resists and suddenly  
gives up. My experience is that the person resists until their arm is  
pushed past the vertical some distance. It appears to me that the strong  
muscles of the shoulder, back, and chest that are effective at the peak  
of the arc and increasingly so as they push down past the peak are  
disadvantaged ‘behind’ the peak of the arc and increasingly so as they  
push up toward the descending arm of the other. As you push forward and  
down, curving the back forward, to some degree the entire upper body is  
being used as a lever whose fulcrum is where you are sitting, and as you  
push past the arc you have your body weight to back you up, as it were.  
As the other pushes your arm back behind you, to lift your arm you are  
curving your shoulder and to some extent your back backward and lifting  
your upper body weight as well as the weight of the other transmitted by  
their muscular effort. This is why getting past the top of the arc is the  
whole game in almost every arm wrestling contest. I believe this has much  
to do with the ‘giving up’ in this situation. Also, unless the person is  
a neophyte at arm wrestling they remember that it is nearly impossible to  
recover once they’ve lost that crucial ground at the balance point.  
_Nevertheless_ you do see people resisting until their arm is  
actually pressed against the table and indeed it is possible to do this  
yourself. So if there is an automatic mechanism for ‘giving up’ and arm  
wrestling provides an instance of it, this deliberate prolongation of  
fruitless effort shows that it is possible for a higher control system to  
override that mechanism. So you have the intervention of higher control  
systems even if you add the UEC/NEC to the model.

Therefore, if an alternative explanation is possible with the  
intervention of higher control systems, that explanation does not add any  
complexity, because the intervention by higher control systems has to be  
there anyway even if you have the UEC/NEC mechanism.

```
    /Bruce
```

---

<div class="post-metadata">

**Author:** ![Bill\_Williams\_UMKC](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/b/48db29/32.png) [@Bill\_Williams\_UMKC](http://discourse.iapct.org/u/Bill_Williams_UMKC)\
**Post date:** [May 22, 2002, 11:58pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/3 "2002-05-22T23:58:27Z")

</div>

[From Bill Williams 22 May 02 CST 19:00]

> [From Bruce Nevin (2002.05.22 15:11 EDT]
> 
> First we need clear instances of the phenomenon.

I don't think you've explained why you don't see the superior good in the  
Giffen effect as an instance of the phenomena. From a position in which there  
is more than enough money for the consumer to supply calories by consuming the  
superior good, an increase in price will result in first more money being spent  
on the superior good, and then when the budget and caloric lines crossing less  
money being spent on the superior good. This seems to me could be considered an  
instance of the phenomena.

Bill Williams

> **···**
>
> \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_  
> Do you want a free e-mail for life ? Get it at [http://www.email.ro/](http://www.email.ro/)

---

<div class="post-metadata">

**Author:** ![Richard\_Marken2](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/r/edb3f5/32.png) [@Richard\_Marken2](http://discourse.iapct.org/u/Richard_Marken2)\
**Post date:** [May 23, 2002, 12:53am UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/4 "2002-05-23T00:53:22Z")

</div>

[From Rick Marken (2002.05.22.1800)]

Bruce Nevin (2002.05.22 15:11 EDT)

> The UEC or NEC (I thought that was a Japanese computer company) is a  
> proposed mechanism to account for the phenomenon of 'giving up'

I think the UEC is an explanation of "giving up" control actions without  
"giving up" the reference for the controlled variable. So "giving up"  
is kind of an ambiguous way of describing the phenomenon explained by  
the NEC. It's giving up my efforts to consume the Jack Daniels that I  
still want, for example.

This is not an easy phenomenon to demonstrate. It is not demonstrated,  
for example, by simply seeing that I no longer act to consume Jack  
Daniels (that I no longer produce a particular controlled result). I may  
not be drinking Jack Daniels because I no long want (have a reference)  
for it. If that's the case, then we already have an explanation for  
\_that\_ phenomenon: hierarchical control. What we have to show is both  
that I no longer consume Jack Daniels \_and\_ that I \_want\_ to consume it  
and \_will\_ consume it if error (the difference between my goal and the  
intended result) is made \_small\_ enough!

I think we need to develop clever, artificial situations to demonstrate  
this phenomenon (\_if it occurs\_). I am not sure it \_does\_ occur. It  
\_seems\_ to me that it does occur. But that's just my subjective  
experience. I'm still working on an experimental demo of the NEC  
phenomenon. So far, no luck.

The NEC is, thus, an explanation for a phenomenon that may not actually  
exist. I think it does exist but demonstrating its existence will not be  
easy. Again, this is because any such demonstration must show clearly  
that the controller has given up the actions but \_not\_ the goal of  
control.

> Buridan's ass and the pill bug are not instances for reasons  
> discussed.

Probably not. I agree.

> The ill-mannered horse bolting for the barn to be fed is I believe not  
> an instance for reasons that I described:

I think this one is still pending. Your explanation (hierarchical  
control) might be right; but the NEC could be right, too. We don't know,  
from observation alone, whether the horse gave up the goal of getting to  
the barn (as per your explanation) or not (as per the NEC explanation).

I think the only way to approach this question (whether or not there is  
an NEC phenomenon) is to do the research that reveals it. Of course,  
that places the burden on those of us who think there \_might\_ be an NEC  
phenomenon. Those of you who don't believe in such a phenomenon can rest  
easy because there has been no demonstration of it. So the UEC  
hypothesis is, at worst, unnecessary

Best regards

Rick

> **···**
>
> ---  
> Richard S. Marken  
> MindReadings.com  
> marken@mindreadings.com  
> 310 474-0313

---

<div class="post-metadata">

**Author:** ![Bill\_Williams\_UMKC](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/b/48db29/32.png) [@Bill\_Williams\_UMKC](http://discourse.iapct.org/u/Bill_Williams_UMKC)\
**Post date:** [May 23, 2002, 1:13am UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/5 "2002-05-23T01:13:50Z")

</div>

[From Bill Williams 22 May 02 CST 20:]

There have been experimental economic studies in which a consumer buys an  
icecream cone for one price. Then the consumer is offered an increasing  
sequence of prices for the icecream cone. But, the consumer demands quite a bit  
more for the cone than the purchase price. This result creates difficulties for  
the orthodox economic theory of choice-- which would lead one to think that the  
consumer ought to be willing to sell the cone for only slightly more than was  
paid for it.

Bill williams

> **···**
>
> \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_  
> Do you want a free e-mail for life ? Get it at [http://www.email.ro/](http://www.email.ro/)

---

<div class="post-metadata">

**Author:** ![bnhpct](http://discourse.iapct.org/user_avatar/discourse.iapct.org/bnhpct/32/34_2.png) [@bnhpct](http://discourse.iapct.org/u/bnhpct)\
**Post date:** [May 23, 2002, 3:29am UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/6 "2002-05-23T03:29:32Z")

</div>

[From Bruce Nevin (2002.05.22 15:11 EDT]

Bill Williams (22 May 02 CST 19:00) –

> **···**
>
> At 02:58 AM 5/23/2002 +0300, William Williams wrote:
> 
> > I don’t think you’ve explained why you don’t  
> > see the superior good in the
> > 
> > Giffen effect as an instance of the phenomena.
> 
> You’re right, I forgot that. Mea culpa. This looks like an instance of  
> the _phenomenon_, but the model that produces this behavior does so  
> by the interaction of control systems, it does not depend upon a UEC or  
> NEC mechanism to do so. So it’s a counterexample to the UEC/NEC  
> _explanation_ of the phenomenon.
> 
> ```
> /Bruce
> 
> ```

---

<div class="post-metadata">

**Author:** ![Bill\_Williams\_UMKC](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/b/48db29/32.png) [@Bill\_Williams\_UMKC](http://discourse.iapct.org/u/Bill_Williams_UMKC)\
**Post date:** [May 23, 2002, 3:49am UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/7 "2002-05-23T03:49:03Z")

</div>

> [From Bruce Nevin (2002.05.22 15:11 EDT]
> 
> Bill Williams (22 May 02 CST 19:00) --  
> \>I don't think you've explained why you don't see the superior good in the  
> \>Giffen effect as an instance of the phenomena.
> 
> You're right, I forgot that. Mea culpa. This looks like an instance of the  
> phenomenon, but the model that produces this behavior does so by the  
> interaction of control systems, it does not depend upon a UEC or NEC  
> mechanism to do so. So it's a counterexample to the UEC/NEC explanation of  
> the phenomenon.

OK. So, maybe it would be helpful if a distinction could be introduced between  
UEC/NEC as a caption for a Phenomena and UEC/NEC as a caption for an  
explaination?

Bill Williams

> **···**
>
> > At 02:58 AM 5/23/2002 +0300, William Williams wrote:
> 
> \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_  
> Do you want a free e-mail for life ? Get it at [http://www.email.ro/](http://www.email.ro/)

---

<div class="post-metadata">

**Author:** ![Richard\_Marken2](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/r/edb3f5/32.png) [@Richard\_Marken2](http://discourse.iapct.org/u/Richard_Marken2)\
**Post date:** [May 23, 2002, 1:49pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/8 "2002-05-23T13:49:51Z")

</div>

[From Rick Marken (2002.05.23.0850)]

Bruce Nevin (2002.05.23 11:17 EDT) --

> \>  
> \>it would be helpful if a distinction could be introduced between  
> \>UEC/NEC as a caption for a Phenomena and UEC/NEC as a caption for an  
> \>explanation?
> 
> Indeed.
> 
> As a phenomenon or as a family of phenomena, we are looking for examples.  
> The Giffen effect seems to be an example, maybe the only sure example we  
> have so far.

The Giffen effect seems to be a clear cut example of hierarchical control. It  
doesn't look like a NEC phenomenon to me.

The Giffen effect is paradoxical only if we look at the relationship between  
the price of and consumption of one product, say, bread. What we see is that  
an increase in price leads to an \_increase\_ in consumption of bread. This  
relationship between price and consumption is paradoxical only in the context  
of certain (admittedly common) assumptions about what the relationship between  
these variables \_should\_ be. But when you look at the picture from a  
hierarchical control perspective there is nothing paradoxical happening at  
all. The consumer is adjusting consumption of a variety of different foods,  
each costing a different amount, as the means of controlling both caloric  
intake and expenditures simultaneously. A simple, two level hierarchy of  
control systems readily accounts for this result (when the higher level  
reference for expenditures is set to an appropriately low -- poor -- level).

The NEC phenomenon is a decrease in effort with an increase in error and an  
increase in effort with a decrease in error. This seems to be happening in the  
horse and barn example. As the horse moves away from the barn (resulting in a  
presumed increase in error) there is eventually a decrease in effort (the  
horse stops trying to get back to the barn) and as the horse returns to the  
barn there is a sudden \_increase\_ in effort as the horse starts getting close  
to the barn (resulting in a presumed decrease in error). So the horse and barn  
phenomenon seems like it \_might\_ be based on a NEC. But it might not; the  
horse may be revising it's reference for distance to the barn depending on its  
distance from the barn; so the phenomenon may actually be based on  
hierarchical control; but at least it \_looks like\_ it could be based on a NEC.  
I don't see why you think the Giffen effect suggests a NEC.

Best regards

Rick

> **···**
>
> > At 06:49 AM 5/23/2002 +0300, William Williams wrote:
> 
> --  
> Richard S. Marken, Ph.D.  
> The RAND Corporation  
> PO Box 2138  
> 1700 Main Street  
> Santa Monica, CA 90407-2138  
> Tel: 310-393-0411 x7971  
> Fax: 310-451-7018  
> E-mail: rmarken@rand.org

---

<div class="post-metadata">

**Author:** ![Richard\_Marken2](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/r/edb3f5/32.png) [@Richard\_Marken2](http://discourse.iapct.org/u/Richard_Marken2)\
**Post date:** [May 23, 2002, 2:14pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/9 "2002-05-23T14:14:11Z")

</div>

[From Rick Marken (2002.05.23.0915)]

Bruce Nevin (2002.05.23 11:17 EDT) –

> Actually there _are_ other examples of the phenomenon  
> in existing control theory demos. We know what the control systems in the  
> demos are doing that results in the appearance of ‘giving up’. This can  
> help us to look with a discriminating eye at the appearance of ‘giving  
> up’ in [our perceptions of] the natural world around us.  
> Again, what is “giving up”? Is it “giving up” actions while the reference  
> for input remains or is it giving up the reference for input itself? The  
> NEC explains the former type of “giving up” (if it happens); hierarchical  
> control explains the latter. You cannot tell what type of “giving up” is  
> actually occurring by simply looking – even with a “discriminating eye”  
> – at the appearance of behavior.  
> I don’t believe there is any _valid_ way to resolve the question of  
> whether or not there is really a need for the NEC hypothesis other than  
> by doing the appropriate PCT-based research. Modeling _alone_ won’t do  
> it. You’ve got to “dare to disturb” the universe. That is, you’ve  
> got to carefully push on some controlled variables and see what happens.

Best regards

Rick

> **···**
>
> * * *
> 
> Richard S. Marken, Ph.D.
> 
> The RAND Corporation
> 
> PO Box 2138
> 
> 1700 Main Street
> 
> Santa Monica, CA 90407-2138
> 
> Tel: 310-393-0411 x7971
> 
> Fax: 310-451-7018
> 
> E-mail: [rmarken@rand.org](mailto:rmarken@rand.org)

---

<div class="post-metadata">

**Author:** ![bnhpct](http://discourse.iapct.org/user_avatar/discourse.iapct.org/bnhpct/32/34_2.png) [@bnhpct](http://discourse.iapct.org/u/bnhpct)\
**Post date:** [May 23, 2002, 3:17pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/10 "2002-05-23T15:17:39Z")

</div>

[From Bruce Nevin (2002.05.23 11:17 EDT]

> it would be helpful if a distinction could be introduced between  
> UEC/NEC as a caption for a Phenomena and UEC/NEC as a caption for an  
> explanation?

Indeed.

As a phenomenon or as a family of phenomena, we are looking for examples. The Giffen effect seems to be an example, maybe the only sure example we have so far.

As an explanation, the label has referred to the proposal that something in the output function of control systems is the cause of the phenomenon. An advantage is that if this is valid then modelers can write a bit of code once and use it everywhere.

To make the distinction, maybe we should reserve NEC for the phenomenon and use related terms that refer specifically to the class of mechanisms being proposed. For example:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NECOF -- NEC from an output function mechanism  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NECCI -- NEC from control system interaction  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NECS -- NEC from control of a sequence

as distinct from

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NEC -- Nonlinear error curve contrary to expectation,  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;either reducing output despite increasing error  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;('giving up') or increasing output despite  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;diminishing error. Unequivocal instances are  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;being sought.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;/Bruce

> **···**
>
> At 06:49 AM 5/23/2002 +0300, William Williams wrote:

---

<div class="post-metadata">

**Author:** ![bnhpct](http://discourse.iapct.org/user_avatar/discourse.iapct.org/bnhpct/32/34_2.png) [@bnhpct](http://discourse.iapct.org/u/bnhpct)\
**Post date:** [May 23, 2002, 3:36pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/11 "2002-05-23T15:36:13Z")

</div>

[From Bruce Nevin (2002.05.23 11:17 EDT]

Bruce Nevin (2002.05.23 11:35 EDT)–

> The Giffen effect seems to be an example,  
> maybe the only sure example we have so far.

Actually there _are_ other examples of the phenomenon in existing  
control theory demos. We know what the control systems in the demos are  
doing that results in the appearance of ‘giving up’. This can help us to  
look with a discriminating eye at the appearance of ‘giving up’ in [our  
perceptions of] the natural world around us.

In the e. coli chemotaxis demo, the agent could be said to ‘give up’  
because of rising error when it starts tumbling. (The e. coli organism  
‘gives up’ consuming nutrients and starts expending energy  
tumbling.)

In the Crowd demo, we frequently observe an agent ‘giving up’ a path  
toward its target and backtracking. Indeed, we might say this of a person  
making a way through a crowd, that they ‘gave up’ trying to get through  
where there were lots of people and backtracked to try another  
route.

What other examples of the appearance of ‘giving up’ can we see in our  
existing demos? Are there any examples of the converse, increasing effort  
as error diminishes?

```
    /Bruce

```

> **···**
>
> At 11:17 AM 5/23/2002 -0400, I said:

---

<div class="post-metadata">

**Author:** ![Richard\_Marken2](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/r/edb3f5/32.png) [@Richard\_Marken2](http://discourse.iapct.org/u/Richard_Marken2)\
**Post date:** [May 23, 2002, 6:31pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/12 "2002-05-23T18:31:40Z")

</div>

[From Rick Marken (2002.05.23.1330)]

Me

> \> I don't see why you [Bruce Nevin] think the Giffen effect suggests a NEC.

Bill Williams (23 May 02 CST 13:30)

> Its the behavior of the superior good that looks as if it might be an instance  
> of a Non-linear Error Curve. If the budget is well above the level required to  
> purchase all of the calories by consuming only the superior good then-- when the  
> price of the superior good is increased, \_at first\_ the amount expended on the  
> superior good increases. Then when the price of the superior good has risen to  
> the point that it is neccesary to consume some of the inferior good to ubtain  
> the required calories \_then\_ expenditures which had gone to the superior good  
> will begin to shift into the cheaper source of calories. So, first as a result  
> of the price increase for the superior good expenditure increase, and then when  
> the price increases still further expenditures on the superior good begin to  
> decrease.

Ah. I think I see. The consumption of the superior good is the controlled variable.  
The amount expended on the superior good is the action used to get the amount  
consumed to its reference level. The price of the superior good is a disturbance to  
consumption of that good. So what you are referring to is the relationship between  
action and disturbance, which is an inverted U: as the price of the superior good  
(disturbance) goes up the amount purchased (action) first increases and then  
decreases. This inverted U looks like an NEC and \_would be\_ an NEC if the  
disturbance were actually proportional to error. Is this right, Bill?

This is a good example of an apparent NEC, since we know that, in the model,  
anyway, the change in action results from a change in the reference for the amount  
of superior good consumed.

Best regards

Rick

> **···**
>
> ---  
> Richard S. Marken, Ph.D.  
> The RAND Corporation  
> PO Box 2138  
> 1700 Main Street  
> Santa Monica, CA 90407-2138  
> Tel: 310-393-0411 x7971  
> Fax: 310-451-7018  
> E-mail: rmarken@rand.org

---

<div class="post-metadata">

**Author:** ![Bill\_Williams\_UMKC](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/b/48db29/32.png) [@Bill\_Williams\_UMKC](http://discourse.iapct.org/u/Bill_Williams_UMKC)\
**Post date:** [May 23, 2002, 6:34pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/13 "2002-05-23T18:34:11Z")

</div>

[From Bill Williams 23 May 02 CST 13:30]

[from Rick Marken]

> \> [frm Bruce Nevin]

> \> As a phenomenon or as a family of phenomena, we are looking for examples.  
> \> The Giffen effect seems to be an example, maybe the only sure example we  
> \> have so far.
> 
> The Giffen effect seems to be a clear cut example of hierarchical control. It  
> doesn't look like a NEC phenomenon to me.
> 
> I don't see why you [Bruce Nevin] think the Giffen effect suggests a NEC.

Its the behavior of the superior good that looks as if it might be an instance  
of a Non-linear Error Curve. If the budget is well above the level required to  
purchase all of the calories by consuming only the superior good then-- when the  
price of the superior good is increased, \_at first\_ the amount expended on the  
superior good increases. Then when the price of the superior good has risen to  
the point that it is neccesary to consume some of the inferior good to ubtain  
the required calories \_then\_ expenditures which had gone to the superior good  
will begin to shift into the cheaper source of calories. So, first as a result  
of the price increase for the superior good expenditure increase, and then when  
the price increases still further expenditures on the superior good begin to  
decrease.

Bill Williams

> **···**
>
> \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_  
> Do you want a free e-mail for life ? Get it at [http://www.email.ro/](http://www.email.ro/)

---

<div class="post-metadata">

**Author:** ![bnhpct](http://discourse.iapct.org/user_avatar/discourse.iapct.org/bnhpct/32/34_2.png) [@bnhpct](http://discourse.iapct.org/u/bnhpct)\
**Post date:** [May 23, 2002, 9:51pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/14 "2002-05-23T21:51:56Z")

</div>

[From Bruce Nevin 2002.05.23 17:51 EDT]

Rick Marken (2002.05.23.1330)--

> **···**
>
> At 01:31 PM 5/23/2002 -0500, Richard Marken wrote:
> 
> > This is a good example of an apparent NEC, since we know that, in the model,  
> > anyway, the change in action results from a change in the reference for the amount  
> > of superior good consumed.
> 
> Keeping the distinction between phenomenon and mechanism to which Bill Williams so astutely called our attention, the Giffen effect is a good example of NEC the phenomenon, but not of NECOF, a mechanism in the output function of control systems whose effect is the NEC phenomenon.
> 
> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;/Bruce

---

<div class="post-metadata">

**Author:** ![Bill\_Williams\_UMKC](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/b/48db29/32.png) [@Bill\_Williams\_UMKC](http://discourse.iapct.org/u/Bill_Williams_UMKC)\
**Post date:** [May 24, 2002, 2:16am UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/15 "2002-05-24T02:16:01Z")

</div>

[From Bill Williams 23 May 02 21:14]

> [From Rick Marken (2002.05.23.1330)]
> 
> Me
> 
> \> \> I don't see why you [Bruce Nevin] think the Giffen effect suggests a NEC.  
> \>  
> Ah. I think I see. The consumption of the superior good is the controlled

variable.

> The amount expended on the superior good is the action used to get the amount  
> consumed to its reference level. The price of the superior good is a

disturbance to

> consumption of that good. So what you are referring to is the relationship

between

> action and disturbance, which is an inverted U: as the price of the superior

good

> (disturbance) goes up the amount purchased (action) first increases and then  
> decreases. This inverted U looks like an NEC and \_would be\_ an NEC if the  
> disturbance were actually proportional to error. Is this right, Bill?

Almost. Starting from an initial condition in which the consumer has more than  
enough money to purchase more than enough meat (the superior good) to supply  
all the calories required, then-- at first when the price of meat increases  
more money will be spent on purchasing meat. So, at first as the price of meat  
increases more will be spent on meat while the consumption of meat stays the  
same. THe "meat error" when the budget line is above the caloric requirement on  
the superior good axis is zero. But, the "output" the money expended to keep  
the meat error zero is increasing with increases in the price of meat. When the  
consumer gets to the point where it is neccesary to purchases some of the  
cheaper ( cheaper in the sense of dollars/unit of calories )good then a "meat  
error" develops. But, this meat error is less urgent than the possiblity of  
developing a caloric errror. Therefore, to prevent a caloric error  
expenditures shift from meat to expenditures on some cheaper source of calories  
like bread or potatoes. This generates a plot for the price of meat vs  
expenditures on meat in which at first the expenditures on meat increase in  
proportion to the increasing price of meat-- up to the point at which it is  
neccesary to shift consumption away from meat to a cheaper source of calories.  
At this point the relationship between the price of meat and the expenditures  
on meat shifts. Now, further increases in the price of meat generate a  
decrease in expenditures on meat.

This, the reaction of expenditures on meat-- first increasing and then  
decreasing as the price of meat is increased, isn't the relationship upon which  
the Giffen Paradox literature has focused. Orthodox economists are bothered by  
the possiblity that there might be a good for which an increase in the price of  
the good generates an increase in the volume of the good purchased. They worry  
about this possiblity because--- if such behavior actually occurs, then they  
will not be able to assume stablity in the market-- where they need to be able  
to believe that a small disturbance ( a price ) increase will generate a  
"negative feedback." If the intial price increase results instead in more of  
the good being demanded, then this it is thought will generate a price increase  
in the market and the "positive feedback" will destroy their argument that the  
market is always stable and consumer behavior will always generate equilibrium  
and other good stuff.

The point I think regarding the behavior of the superior good ( meat ) is that  
using ordinary control loops, an output "expenditure" is generated that first  
increases as the disturbance ( the price increases ) is applied and then at  
some definable point begins to switch and generate a decrease in response to  
still further price increases. It doesn't quite match the UEC in the sense  
that while the price of meat is a first generating more output ( expenditure )  
the error for meat consumption remains at zero. So, what is involved is a  
disturbance to output relationship rather than an association between error and  
output. The peculiar feature of this case may be a result of the increasing  
disturbance, at first, not generating an error.

Bill Williams

> **···**
>
> \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_  
> Do you want a free e-mail for life ? Get it at [http://www.email.ro/](http://www.email.ro/)

---

<div class="post-metadata">

**Author:** ![Bill\_Powers1](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/b/8e7dd6/32.png) [@Bill\_Powers1](http://discourse.iapct.org/u/Bill_Powers1)\
**Post date:** [May 24, 2002, 2:30am UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/16 "2002-05-24T02:30:22Z")

</div>

[From Bill Powers (2002.05.23.1951 MDT)]

Bruce Nevin (2002.05.23 11:17 EDT)--

\>In the e. coli chemotaxis demo, the agent could be said to 'give up'  
because of rising \>error when it starts tumbling. (The e. coli organism  
'gives up' consuming nutrients \>and starts expending energy tumbling.)

> In the Crowd demo, we frequently observe an agent 'giving up' a path  
> toward its target and backtracking. Indeed, we might say this of a person  
> making a way through a crowd, that they 'gave up' trying to get through  
> where there were lots of people and backtracked to try another route.
> 
> What other examples of the appearance of 'giving up' can we see in our  
> existing demos? Are there any examples of the converse, increasing effort  
> as error diminishes?

The only reason these examples can "be said" to show the "giving up"  
phenomenon is that the meaning of the term changes, and we use a very  
liberal interpretation of what we see. I would not like to see the  
phenomenon trivialized in that way -- if it really is that trivial, we  
should just forget about it.

Perhaps someone with access to a large University library can find the  
paper describing the effect as I first heard of it. The authors will (I  
believe) be Dollard and Miller, or perhaps one of them alone, although the  
first author could have been a graduate student. The subject is "approach  
gradients," and the observation was that as a rat approached a food dish,  
its efforts to get closer increased, as measured through a tether  
restraining the rat. It is this effect we have to explain, although if it  
is seen only in rats and only in that experiment, finding an explanation  
may not be very important. Look up \_Dollard Miller approach gradient\_ in  
Google and you'll see what you get into.

I'm concerned about that experiment, because it seems to contradict PCT: as  
any error gets smaller, the effort used to correct it ought to get smaller,  
or its rate of increase ought to be smaller. Instead, the proximity of the  
food dish seems to serve as a stimulant to the approach efforts, which is  
of course the S-R interpretation Dollard and Miller put on that sort of  
thing. Whoever did that experiment should have sensed something wrong,  
because if the effort really kept increasing all the way to the food dish,  
the rat should have gone shooting by it instead of stopping to eat. But we  
still have to worry about the behavior far from the food dish. And at least  
as I do things, I can't explain it just by cooking up some imaginary  
higher-level systems defined so they will do just what we observe. If  
that's all that's happening, there are too many scenarios that would give  
the same appearance, and none of them is compelling for that reason.

A key feature of this phenomenon was that there was a \_gradient\_ of effort,  
so the effort was a smooth function of distance (in the wrong direction for  
PCT). That is hard to explain in terms of a logical system that is  
reasoning symbolically about what's happening. Whatever is creating the  
appearance of a change in gain is doing it in an analog fashion.

We can model a system in which the gain of the output function is high for  
errors below some threshold and declines for errors above that threshold in  
proportion to the excess. We don't need to say what is causing the gain to  
decline with increasing error in this way -- whether it's a learned  
algorithm, competition between contradictory goals, something  
physiological, or merely an illusion created as something else entirely is  
controlled. The explanation will not alter the effect of having an output  
function behave in that way as the error changes.

The simplest simulation experiment will be to vary the sensitivity of the  
gain-changing relationship to excess error. With zero sensitivity, the  
effort will simply go on increasing as long as the error increases. As the  
sensitivity is slowly raised, we will start to see the increase of effort  
falling below a linear relationship. At some sensitivity, the effort will  
just level off, as if the output function were saturating, and at still  
higher sensitivities we will start to see the effort decreasing as error  
increases further (and of course, increasing if the error then decreases).

These changes in the output function will not be directly reflected in the  
relationship between disturbance and effort. A lot will depend on the  
feedback function and the disturbance function. If the disturbance is  
coupled to the controlled variable as through a spring, it is likely that  
the whole system will become unstable at the critical point, or begin to  
behave as a flip-flop as the error fluctuates around the critical point.  
This should give us a better idea of the kinds of relationships we should  
look for in real behavior. It will certainly help us distinguish the sort  
of "giving up" behavior that results from this ertror-effort relationship  
from other behavior that might also fall into a category indicated by those  
words.

I'm fooling around with Bill Williams' source code for the Ass and will  
communicate about the results if there are any.

Best,

Bill P.

---

<div class="post-metadata">

**Author:** ![bnhpct](http://discourse.iapct.org/user_avatar/discourse.iapct.org/bnhpct/32/34_2.png) [@bnhpct](http://discourse.iapct.org/u/bnhpct)\
**Post date:** [May 24, 2002, 3:29am UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/17 "2002-05-24T03:29:38Z")

</div>

[From Bruce Nevin (2002.05.23 23:28 EDT)]

Bill Powers (2002.05.23.1951 MDT)--  
The only reason these examples can "be said" to show the "giving up"

> phenomenon is that the meaning of the term changes, and we use a very  
> liberal interpretation of what we see.

The point of bringing this up is that all we have initially is what we see. In the models we know what is going on. When we observe something happening in nature or in the laboratory we don't. The models, as always, are instructive as to what might be going on behind the appearances in nature or in the laboratory.

> the observation was that as a rat approached a food dish,  
> its efforts to get closer increased, as measured through a tether  
> restraining the rat.

We're assuming that the rat is controlling the quantity 'distance from food', that error is inversely proportional to distance (or directly proportional to proximity to the food), and that this is all that is going on.

If I'm lifting a heavy rock, and I've almost got it to the top, I exert tremendous effort, as much as I can, to put it over the top. Why is that? My rationalization of this is that I make extra effort because I'm almost there and also because if I don't get there on this try the chances of getting there on a second try aren't likely to be better. And I want to get on with whatever it was that I was lifting that rock up there for, or whatever I was going to do next.

Suppose this is a sequence that the rat is controlling:

1. Move mouth close to food.  
2. Eat.

Then error in the sequence control system is due to Step 1 not being completed. It seems to me, subjectively, that if a step in a sequence is almost completed (and the sequel is desired rather than averted) the gain increases for completing that step and proceeding to the next.

Some experimentation and modelling of sequence control might determine whether this is true, and could provide more insight into the rat experiment.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;/Bruce

> **···**
>
> At 08:30 PM 5/23/2002 -0600, Bill Powers wrote:

---

<div class="post-metadata">

**Author:** ![Richard\_Marken2](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/r/edb3f5/32.png) [@Richard\_Marken2](http://discourse.iapct.org/u/Richard_Marken2)\
**Post date:** [May 24, 2002, 5:30am UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/18 "2002-05-24T05:30:25Z")

</div>

[From Rick Marken (2002.05.23.2230)]

Bill Powers (2002.05.23.1951 MDT)

> Perhaps someone with access to a large University library can find the  
> paper describing the effect as I first heard of it. The authors will (I  
> believe) be Dollard and Miller, or perhaps one of them alone, although the  
> first author could have been a graduate student. The subject is "approach  
> gradients," and the observation was that as a rat approached a food dish,  
> its efforts to get closer increased, as measured through a tether  
> restraining the rat. It is this effect we have to explain, although if it  
> is seen only in rats and only in that experiment, finding an explanation  
> may not be very important. Look up \_Dollard Miller approach gradient\_ in  
> Google and you'll see what you get into.

I do remember that study, vaguely (I think I saw it referred to in an  
undergraduate course on "Motivation"). I can cull up an image of it from  
memory. The image is a picture of a rat wearing a harness that is connected to  
a force measuring device. I don't have a memory of the force distance plot,  
if such a plot was presented. I looked on Google and found articles that refer  
to Miller and Dollard's approach-avoidance "theories" and their notion of an  
approach gradient. But no reference to that particular "rat harness" study.  
Finding this study may require some effort, which may increase as I get closer  
to it. If anyone can find it I bet Bruce Abbott can!

Best

Rick

> **···**
>
> --  
> Richard S. Marken  
> MindReadings.com  
> marken@mindreadings.com  
> 310 474-0313

---

<div class="post-metadata">

**Author:** ![DAVID\_WOLSK1](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/d/13edae/32.png) [@DAVID\_WOLSK1](http://discourse.iapct.org/u/DAVID_WOLSK1)\
**Post date:** [May 24, 2002, 6:38pm UTC](http://discourse.iapct.org/t/uec-nec-summary/11863/19 "2002-05-24T18:38:07Z")

</div>

snipped

> I'm concerned about that experiment, because it seems to contradict PCT:

as

> any error gets smaller, the effort used to correct it ought to get

smaller,

> or its rate of increase ought to be smaller. Instead, the proximity of the  
> food dish seems to serve as a stimulant to the approach efforts, which is  
> of course the S-R interpretation Dollard and Miller put on that sort of  
> thing. Whoever did that experiment should have sensed something wrong,  
> because if the effort really kept increasing all the way to the food dish,  
> the rat should have gone shooting by it instead of stopping to eat. But we  
> still have to worry about the behavior far from the food dish. And at

least

> as I do things, I can't explain it just by cooking up some imaginary  
> higher-level systems defined so they will do just what we observe. If  
> that's all that's happening, there are too many scenarios that would give  
> the same appearance, and none of them is compelling for that reason.
> 
> A key feature of this phenomenon was that there was a \_gradient\_ of

effort,

> so the effort was a smooth function of distance (in the wrong direction

for

> PCT). That is hard to explain in terms of a logical system that is  
> reasoning symbolically about what's happening. Whatever is creating the  
> appearance of a change in gain is doing it in an analog fashion.

As someone who spends time in the woods following trails with choice points,  
on the way to a goal, I think I speed up as I gain confidence that I'm  
making the right choices. That's obviously not a smooth gradient, but I  
doubt if the measurement of the rats was that fine.  
David Wolsk

> **···**
>
> ----- Original Message -----  
> From: "Bill Powers" \<powers\_w@FRONTIER.NET\>  
> To: \<CSGNET@listserv.uiuc.edu\>  
> Sent: Thursday, May 23, 2002 7:30 PM  
> Subject: Re: UEC/NEC summary