Hi All,
This thread on extracting models from written documents generates a
certain Aha-erlebnis, as the germans would probably say.
The ratio behind the initial request seems to be the availability of a
tool that does the hard work:
extracting knowledge from certain sources.
If that would be possible, it would leave more time to the real SD-work.
John Gunkler stated:
>(...) And the people who have been working for two decades on what
>was initially called "artificial intelligence" (especially, expert
>knowledge capture) have developed protocols for interviewing "expert"
>subjects. Perhaps there is something quite useful that we could tap
>from their experience. It seems to me that capturing "mental models"
>and capturing "expert knowledge" of some circumscribed subject area are
>very similar exercises.
>
The suggestion made, is that AI might have come up with certain results
the SD community could use.
As far as I know this is not the case. One might even question the
possibility of extracting knowledge from written sources.
The same question arose in the AI and Law community some 10 to 15 years
ago. Then, the research started
with high expectations aiming at the development of knowledge systems
which could accept as input a certain
story - text based - and generate as output a legally acceptable
reasoning and options for solutions.
This result has never been reached and there are lots of reasons why it
didnt and probably never will.
One of the interesting observations which can be made with respect to
this research, is that it also
wanted to extract knowledge from experts: either by using thinking-
aloud protocols or by analysing
written sources (such as legal cases). Based on the idea: if we could
detect how experts handle a case - or
a problem - one could deduct from this a certain protocol how (other)
problems should or could be tackled.
Jac Vennix already reported on this list on his experiences with the
frist type:
>Just a cautionary note on extracting models from written documents. I have
>done something along those lines for my PhD research. I extended the coding
>procedure as described in Axelrods book. However, even after extensive training
>of six students in extracting clds from written pieces of text (guided by
>a coding procedure book), I was not able to get a sufficient inter coder
>reliability (i.e. > 0.80). Now this was over 10 years ago, but I do not
>have the impression that much has changed in the last decade wrt this issue.
>
The latter one - extracting knowledge from written texts (in terms of
general rules) - also failed.
One of the main reasons is - in short - that knowledge is not static: it
developes and changes.
Using any method of extracting knowledge implies that the result is by
principle outdated.
Particularly within the legal domain this is unacceptable. Also, the
result is very hard to be validated, since,
almost any outcome in a legal dispute is possible. It depends on the
line of argumenation. And that relates to
the basic idea in SD: a different question or RMoB of a certain problem
may generate different models.
Just like Sterman has put it: the actual validation of models is impossible.
The usage of (the strict meaning of) validation within SD is a
contraditio in terminis.
A second point is that any written text is in itself the result of an
extracting method, though most of
the time done by the expert himself. Any text therefore is double
biased: first, there is the perception of
this particular expert, and second, there is - again - the subjective
representation of his perception
in words. And even a third stage: the subjective perception of this text
by the reader ...
A third point is that SD - just like the legal domain - depends on
argumentation or, as it is put
by Forrester and Senge: building confidence.
We do not just present a model, we argue about it while creating is. One
is not convicted
just because the judge says so, but - in ideal circumstances - because
the judge is convinced that
this particular outcome is the most reasonable one AND he - the judge -
does motivate this point of view.
This implies that a black box is never acceptable: we have to be convinced
of the soundness of the proposed way of handling a certain problem. In
skipping this part, leaving it
to a sophisticated - if ever possible - knowledge-modelling tool, one
would diminish one of the most
important- though hard - parts in SD.
Greetings,
Carolus Grütters
Law & IT
University of Nijmegen
The Netherlands
From: Carolus =?ISO-8859-1?Q?Gr=FCtters?= <
c.grutters@jur.kun.nl>