[From Rick Marken (2003.11.28.0910)]
Marc Abrams (2003.11.28.0904)
> You say that we need a "working model of HPCT.
_YES_ (Not shouting, just really emphasizing)
> What do you have in mind?
Nothing specific and concrete at this point, just _a lot_ of ideas. For
instance, I believe we need to bring emotion and memory into the model.
In my paper _Looking at behavior through control theory glasses_
(Review of General Psychology, 6, 260�270, 2002) I describe several
working models of behavior. Several are hierarchical control models.
None of them explicitly incorporates memory or emotion but all produce
behavior that is very similar to the behavior they were designed to
imitate (catching fly balls, balancing brooms, pointing at targets,
moving through crowds, etc.). Does this mean that they are not really
working HPCT models, from your point of view?
> How will you recognize that we have a working model of HPCT?
When the model can produce the predicted results of the theory
How about when the model can produce the actual results that are
My spreadsheet hierarchy model certainly produces the predicted results
of hierarchical PCT: successful simultaneous control of several
perceptions of the same _type_ by systems at one level of of the
hierarchy by systems that achieve these perceptions by varying lower
outputs that have direct effects on the environment or that determine
the references for lower level systems.
Other models, such as the simple integrated output with transport lag
model of tracking, predict actual behavioral results. A simple
one-level control model nearly perfectly predicts behavior in a
polarity reversal experiment. Try the "Levels of Control" demo at
http://www.mindreadings.com/ControlDemo/Levels.html. When you complete
a run, the filled squares plot the behavior of a one-level model, which
is a prediction of how you will behave when the polarity of the
connection between mouse and handle suddenly changes. The open squares
are your actual behavior. If the plot of your behavior matches the
behavior of the model the model has successfully predicted your
behavior. This is a true prediction because the model has no idea what
you are going to do when the polarity changes. The model can also
predict your "adaptation" to the polarity change that occurs about 1/2
second after the change but this requires adding another level of
control to the model.
I am frankly amazed that your complaints about PCT (or HPCT) are about
it being neither a "working model" nor "predictive". Maybe I've spent
too many years being a lapdog but it seems overwhelmingly clear to me
that my master has developed a theory of behavior that is not only
implemented as a working model but that predicts behavior with
Richard S. Marken
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