Josh,

On 4/11/08, J Storrs Hall, PhD <[EMAIL PROTECTED]> wrote:
>
> Actually, the medical expert systems of the 80s I had any conection with,
> such
> as the glaucoma expert from Rutgers, beat out human doctors in diagnoses
> within their field of expertise.  (And still weren't adopted...)


Yes. There was a presentation at the last WORLDCOMP AI conference where a
computer was routinely beating people at identifying details in jaw X-rays,
that were needed to make key measurements to fit prosthetics. This sort of
an approach works well in closed systems that are well understood, but
poorly in "wide open systems" where the goal is to get some handle on a
bad situation, from which to leverage some sort of cure - and possibly even
something that has never before been proposed for that particular ailment.

How can a (simple) computer possibly do this? Because new (to the computer)
cause and effect chains usually have some known (to the computer) links. If
just one link in the lead up to the self-sustaining loop in the cause and
effect chain is known and has a cure, and if just one link in the
self-sustaining loop has any sort of treatment at all, then the condition
can easily be cured for once and for all, even though the overall condition
and diagnosis is completely unknown, and remains unknown to the computer.

BTW, the attached paper included some remarks about Jay Forrester & System
> Dynamics. Forrester came out of exactly the same background as Cybernetics
> --
> working on automatic radar-directed fire-control systems, at MIT, during
> WWII.  And both his stuff and Cybernetics consists basically of applying
> feedback and control theory (and general differential analysis) to things
> ranging from neuroscience to economics.


Like Joe Weizenbaum, Jay Forrester had a REALLY good idea that he put into
his writings, but only as a side note and not any sort of main theme.
However, I'll take a good idea from anywhere that I can find it. That idea
was that when you analyze many similar systems, like corporations, that you
typically find a few common modes of failures from among the countless
possible modes of failure. Once you have gotten to that point, you can
quickly correct most of the failures by simply screening for the common
modes of failure, with no simulation needed.

Jay was fixing corporations that are each unique, though they do operate in
a "standard" world. However, people (and circuit boards and most of the
other things that people might like computers to fix) are MUCH more alike
than corporations, so that most experts already know most of the known modes
of failure - with no computerized analysis needed to identify those
potential modes of failure.

Even military science has remained much as it was millennia ago, as
exemplified by writings like *The Art of War*, despite the emergence of
modern weapons. For example, in Roman times it took ~2% of a population to
occupy it, and that percentage remains true today. That we are attempting to
do this with ~1% of the population of Iraq underlies our failures there.
This was pointed out early in the Iraq conflict, but those generals were
promptly discharged for having a bad attitude.

Steve: If you're saying that your system builds a model of its world of
> discourse as a set of non-linear ODEs (which is what Systems Dynamics is
> bout) then I (and presumably Richard) are much more likely to be
> interested...


No it doesn't. Instead, my program is designed to work on systems that are
not nearly enough known to model. THAT is the state of the interesting (at
least to me) part of the real world.

In short, I am apparently going where no one has gone before - applying new
methods to solving difficult problems in poorly understood systems. I'll
gladly leave the easy stuff (modeling well-understood systems) to others.

BTW, there is a generally unrecognized principle (except to some experienced
System Dynamics types), that the cause and effect chains are LONG and
usually involve some lack of understanding among those who designed the
systems that we must now deal with. Only the most arrogant would presume
their own perfection in comparison with those who designed the world in
which we live. Correcting that arrogance is THE primary benefit of System
Dynamics, which forces people to code how the systems REALLY work (to make
the simulations play like reality) and not just how they THINK that those
systems work.

Hence, simulational System Dynamics must be confined to systems whose
operation can be observed or instrumented. Unfortunately, this lets out most
of the REALLY important real-world problems, especially medicine, from
simulated solution. That reasoning new cures for medical conditions that are
unknown to the computer at once appears to be SO difficult, yet is
relatively easy given the right approach, is why I/we chose chronic illness,
the hardest part of medicine, as our demo.


> ps -- of course, you know that if you're using Excel to integrate
> dynamical
> systems, you are in a state of sin.


(Sigh of relief for not being in a state of sin) Access is VERY different
from Excel. Access is really just Visual Basic with an integrated interface
into relational databases and a forms engine. When writing large/complex AI
programs that will never be fully tested, it is crucial that you generate as
few subtle/hidden bugs as possible, and I can think of no better platform
than VB to accomplish that. It can never be a "VB Puzzle Book" because the
language is SO simple and direct, but the very presence of the "C Puzzle
Book" is grounds for dismissing C as being a serious AI programming
language.

BTW, I have my own thoughts that are VERY different from the mainstream on
what the perfect AI programming language would be like, but that is a
different subject...

Steve Richfield

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agi
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