Ventana software support forum

Hi every body.

When trying to understand what was meant by "learn"
I tried to load learning3.mdl from Mr Richardson,
but could only load it as text and
when I wanted to transform in sketch Vensim said "syntax errors".

I am new to SD and must have made an error.

I feel that without a formal definition of the word "learn" it is rather
impossible to answer the question.
What I mean by formal definition is:

Say that you have two SD Models:
One that cannot learn ant the other that can.
Both have a finite set of definitions and can both be represented by
one of the current SD software.

If you open the cannot model, you can with a finite number of
modifications transform the cannot into the can.
All these modifications can be broken into very simple ones.
What is the simple modification that will transform the cannot into
a can?

Or maybe it is a set of modifications that will transform the cannot
into the can because the can can have the particularity of having
a submodel that gives it the learning power.

Or what is the minimum set of basic modifications that transform the
cannot into a can?
Is it a binary problem yes or no?
Or is it more a capacity of learning?
Can this capacity be measured?
Maybe not with any number integer even infinite or real.
That capacity must be equivalent to the total of knowledge of the
universe which is difficult to evaluate with standard system of measures.

When looking at the different answers it seems that a learning SD Model is
a model that will transform the way it reacts to a similar external stimulus after a
while.
What will cause the transformation? May be experience that is summarized
by exogenous data and the way it reacts to these exogenous data.

It is a sort of educated learning, bounded by the assumptions of the
maker of the model has made about the external word of the model and
by the purpose of the model.

One can imagine that the model can change the way it experiences
things, but it will need a second model to do that. A third model can
modify the second one etc..

Is that education helping the learning process or not?
The ideal solution would be to have a model that can experience without
preconceived idea and able to change without boundaries and without
any preconceived idea about the outside word.

But how can the model start its modification wihout a hint about how to react
at the beginning of its experience?

If education was bad for invention it would not be necessary to be a good
jazz improviser, to know by heart every sort of scales in all keys which takes a long
time. And knowing all the scales helps improvisation nevertheless the preconceived
way to play scales.
Learning the molecules helps creativity in SD Modeling and does not restrict it.

One can too imagine a model that is well educated and that can depending
on the situation forget everything he has learned, to have the possibility to
adjust to an external word different from the one expected.

While finding the subject intellectually interesting I am not presently much concerned
by the question of model learning but more by the model maker learning.

Having started SD last year I hoped at first that SD models would resolve the tricky problems
I have to resolve in my business.

After the Hines-Eberlein distance SD course I rushed to construct SD Models and after
some time I found happily for my mental health that the problem for me
was not to make a certain model but to increase my perception of reality
by constructing and "playing" with different models which is a much softer way to see
things and releaves the pressure to construct the perfect model.

J.J. Laublé.
From: "ALLOCAR SRASBOURG" <allocar-strasbourg@wanadoo.fr>