[Philip 5/5]
RM:At first I didn’t get it but I think I get it now. I think the line labeled “delta” (which I presume is the derivative) is the reference for
the 1st order perception. So maybe what you are saying is that if the perceptual variable controlled at the 2nd level is the integral of the perceptual variable controlled at the 1st order then the 1st order perceptual variable will be controlled relative to a reference that is proportional to the derivative of the 2nd order perception. And that sounds right. Is that what you mean? It would be nice to see a mathematical (or simulation) proof of this.
PY: Yes, exactly.
The output of the 1st order input function, f, is controlled relative to
a reference that is proportional to F’, the derivative of the 2nd order
perception.
RM: Now what would happen if you reversed the order of levels. That is, have the 1st order perception be the integral of its input and the 2nd order perception be the derivative of the 1st order perception. Would it
work? Could you design a control hierarchy where a derivative is controlled by means of varying the reference for the integral of a variable?
PY: I’m not sure what you mean. Do you mean?: let the output of the 1st order input function be the integral of its input; and the let output of the 2nd order input function be the derivative of the output of the 1st order input function. And your question is: can this derivative (the output of the 2nd order input function) be controlled by means of varying the reference compared to the the integral of a vairable (the output of the 1st order input function)?
PY: I’m thinking such a control hierarchy could be designed. But Powers seemed to prefer controlling the integral (position) by means of varying the reference for the derivative (velocity).
···
On Wed, Jun 3, 2015 at 9:30 AM, Richard Marken csgnet@lists.illinois.edu wrote:
[From Rick Marken (2015.06.03.0930)]
[Philip 6/2]
There has been some talk about the nature of input functions in PCT.
Let the output of an input function be the number compared to the reference value.
A first order input function outputs an environmental measurement as a number.
A second order input function outputs the integral of the output of the first order function. Output(2nd-order input) = integral(1st-order input).
The final value of the 1st-order input will thus tend to a value which depends on its time integral. The first dimension is time.
Does this clarify anything?
RM:At first I didn’t get it but I think I get it now. I think the line labeled “delta” (which I presume is the derivative) is the reference for the 1st order perception. So maybe what you are saying is that if the perceptual variable controlled at the 2nd level is the integral of the perceptual variable controlled at the 1st order then the 1st order perceptual variable will be controlled relative to a reference that is proportional to the derivative of the 2nd order perception. And that sounds right. Is that what you mean? It would be nice to see a mathematical (or simulation) proof of this.
RM: Now what would happen if you reversed the order of levels. That is, have the 1st order perception be the integral of its input and the 2nd order perception be the derivative of the 1st order perception. Would it work? Could you design a control hierarchy where a derivative is controlled by means of varying the reference for the integral of a variable?
Best
Richard S. Marken
www.mindreadings.com
Author of Doing Research on Purpose.
Now available from Amazon or Barnes & Noble
Rick
–