[comp.ai] Cognitive System using Genetic Algorithms

joh@wright.EDU (Jae Chan Oh) (01/25/88)

I am working on a learning system using genetic algorithms. And I'm
trying to find some engineering applications using this concept.

I would like to have the informations about real details of the
CS-1(cognitive system-1) by J. Holland, LS-1 by S.F. Smith, or whatever
it is related. ( I have read the articles about thease systems, but the
idea of the "classifier" was not clear to me)

Any hints, literature references, or even source listings are very
appreciated.( source listings will be prefered )

If there is interest, I will summarize the results and will email it.

Thanks in advance.

P.S.: Does any one know the email addresses of J. Holland( U of Michigan),
S.F. Smith ( Carnegie-Mellon, I guess) or anyone who've been related in
genetic algorithms ?

-- 
Jae Chan Oh   CSNET: joh@CS.wright.EDU  UUCP: ...!cbosgd!wright!joh
Wright State University Research Building
3171 Research Blvd, Kettering, Ohio 45420 

g451252772ea@deneb.ucdavis.edu (0040;0000006866;0;327;142;) (01/25/88)

About a month or so ago I complained of the engineering focus of disserta-
tions done by Holland's students.  I got a very nice reply from a former
student, Lashon Booker, who cited a number of more abstract projects 
(including his own).  All these theses are available through U. Microfilms
(which happens to be based in Michigan), at about $25 each.  

Lashon is still quite active; he's at booker@nrl-aic.ARPA.  There is a BBS
for genetic algorithms; to subscribe, send mail to GA-List-Request@nrl-aic.ARPA.
(I did some time ago but have no reply yet... hmmm)

And a standard set of C subroutines for classifier systems is available for 
media cost from Rick Riolo at U.Mich.  Contact him at 
Rick_Riolo@ub.cc.umich.edu for details - I got mine on a 1.2 meg AT disc (just
fits).  Other formats available (Sun, Mac, ... ).  This is ver 0.98, so it's
not totally stable yet.  I'm slowly getting acquainted with it all...

Oh yes: the books INDUCTION, 1986, by Holland et al; GENETIC ALGORITHMS AND
SIMULATED ANNEALING, 1987, L. Davis; and GENETIC ALGORITHMS AND THEIR 
APPLICATION, Proceed. 2nd Intl. Conf. Gen. Alg. (L. Erlbaum Assoc, Pub),
are all of interest.  

I, for one, would be curious what else you learn, although my interests are
more in the theoretical arena (population genetics, et al).  


Ron Goldthwaite / UC Davis, Psychology and Animal Behavior
'Economics is a branch of ethics, pretending to be a science; 
 ethology is a science, pretending relevance to ethics.'

dwt@zippy.eecs.umich.edu (David West) (02/12/88)

In article <1062@ucdavis.ucdavis.edu> g451252772ea@deneb.ucdavis.edu.UUCP (PUT YOUR NAME HERE) writes:
>The author discusses neural nets, 
>simulated annealing, and one example of GA, all applied to the TSP, but
>comments that "... a thorough comparason ... _would be_ very interesting"
  [...]
>o	As noted, the TSP is a canonical candidate.

I believe the TSP is popular because it is easy and compact to program.
The performance of a general method such as GAs can be strongly influenced
by the problem representation, and it turns out that the most straightforward
representations for genetic operations are particularly badly matched to the
most straightforward representations for TSPs.  This makes the TSP a rather
unfortunate choice of introductory example for people who are unfamiliar
with GAs.

>Finally, I noted above that the production rules take system inputs as
>bit-strings.  This representation allows for induction,... 

It is *one* way of getting a form of induction, and has the property that
only very simple operations on the internal representation are used; the 
extent to which this is useful depends, again, on the joint appropriateness 
of the representations of the genetic operators and the world.  
An "appropriate" representation has the property that the expected 
fitness of the result of (say) a crossover is not severely worse than 
that of its parents. This is something that must be ensured by the experimenter
if (as is most common) the representational mapping itself is not subject to
genetic selection.

 -David West