Re: Membership functions.

news (jhughes@SPAM-WHACKERretrostudios.com)
Fri, 25 Jun 1999 05:49:32 +0200 (MET DST)

Earl Cox wrote in message ...
>You should not be surprised that changing the shape of a knowledge base's
>fuzzy sets changes the output control surface of the rules. After all, it
is
>the fuzzy sets that specify the semantics of the rule. If you change the
>shape of a fuzzy set, you change the semantics of the knowledge. The fact
>that the organizational framework -- the rules -- remain the same is
>immaterial. When you change the topology (or, more properly, the
morphology)
>of the fuzzy sets, you change the way the collection of rules behave, you
>change how truth membership grades are transferred, and you change how the
>solution control surface is constructed.
>
>A very simple expert system shows this. Consider a weight estimating system
>of one fuzzy rule,
>
> if height is Tall then weight is Heavy
>
>where Tall is a linear increasing fuzzy set and weight is a right-facing
>S-curve. Running this rule will give us an estimate of weight. If you now
>change the shape of Tall to a skewed S-curve, you will get a very different
>weight estimate. In fact, without changing the rule, you can generate many
>different weight estimating models simply by changing the fuzzy set shapes.
>
>Just a comment.
>Earl
>
>
>Pramit 'Jake' Sarma wrote in message ...
>>A very useful experimental way to check the 'goodness' of MF geometry is
>>by inspecting the input/output surface generated by the fuzzy
>>inferencer with a given rule-base. There can be striking differences in
>>the surface for different MF shapes for the *identical* rule-base.
>>

Has anyone built a public domain or freeware member function editor?
Something simple that reads and writes a text file that describes the fuzzy
set's member functions, using triangular or S/Z representations, and lets
the user graphically inspect and alter the set?

I'm kinda new to the group, but I've been reading comp.ai.fuzzy for a couple
of weeks and have been reading "Fuzzy Logic for Real World Design" by Heske
& Heske, for a project I'm working on. Unless I find something to help do
this for me, it looks like my first real task will be to design a general
purpose fuzzy set editor... seems like that wheel would have been invented
by now somewhere.

Any ideas?

Thanks,
JH
PS-(to reply via email, remove the SPAM-WHACKER from my email)

############################################################################
This message was posted through the fuzzy mailing list.
(1) To subscribe to this mailing list, send a message body of
"SUB FUZZY-MAIL myFirstName mySurname" to listproc@dbai.tuwien.ac.at
(2) To unsubscribe from this mailing list, send a message body of
"UNSUB FUZZY-MAIL" or "UNSUB FUZZY-MAIL yoursubscription@email.address.com"
to listproc@dbai.tuwien.ac.at
(3) To reach the human who maintains the list, send mail to
fuzzy-owner@dbai.tuwien.ac.at
(4) WWW access and other information on Fuzzy Sets and Logic see
http://www.dbai.tuwien.ac.at/ftp/mlowner/fuzzy-mail.info
(5) WWW archive: http://www.dbai.tuwien.ac.at/marchives/fuzzy-mail/index.html