REPLY The Minimum Acceptable Model Standard (SD6764)

[SDMAIL Bill Harris]

Posted by  Bill Harris <bill_harris at facilitatedsystems.com>

"SDMAIL Bill Braun" <bbraun at hlthsys.com> writes:

> > Would an open source authorship approach to this be feasible? It offers the 
> > possibility of moving beyond the limitations that Tom Forest cites. I am not 
> > knowledgeable about the technology used for such an initiative. If there is 
> > energy around the idea, I'll take on the preliminary research.

Do you mean open source with respect to the modeling software, the
model, or the paper?  (I'm not clear on the antecedent of "this.")  All
seem quite doable /if/ the author so desires.  Creative Commons
(http://creativecommons.org/) is one popular approach; the Free Software
Foundation (http://www.fsf.org/) has another, much older, and perhaps
more rigorous approach.  

Anyone can license what they produce under one of their licenses or
under any of a number of others.  http://www.fsf.org/licensing/licenses/
has a rather comprehensive list of such licenses and comments about the
extent of the freedom each offers.  The OSS simulator I use is licensed
under the GNU GPL 2.0 or later.  I could imagine licensing a model under
the GPL (or not).  I could imagine licensing a paper under the GNU FDL
or perhaps one of the Creative Commons licenses (again, or not).

There are challenges.  The journal in which you publish may want the use
of a copyright.  Your client or organization (or perhaps you) may have
proprietary ownership or control concerns.  If you use a GPL'd,
compiling simulator, then the compiled model is automatically GPL'd, and
so you can't distribute a compiled version of a model without also
making the entire source available, which can be a bit of a barrier (and
without granting those same rights to anyone who gets a copy).  At a
minimum and painted in broad brush strokes, I can't legally distribute a
compiled model I build in my OSS tool without also shipping out the
source to the model, the simulator, and the GNU Scientific Library (or
otherwise complying with the requirement to make the source available),
which inflates the package size quite dramatically (and there may be
more GPL'd source linked in that I'd have to identify).  I can
distribute the source code of a GPL'd model with no problems; you'd just
have to build and install the software in order to try it out.

"SDMAIL Bob Eberlein" <bob at vensim.com> writes:
> > I am not sure I see this as a problem, so much as an opportunity. And
> > where I think it directly applies is in the creation of a library, if
> > I may use the term loosely, of models addressing different problems.
> >
> > This is something that I, and a number of others, have been interested
> > in putting together for some time. One of the stumbling blocks has
> > been a framework for acceptability. One possibility was a thorough
> > review by people experienced in the field, the other was simply to let
> > everything in.

Bob,

There's something attractive about that.  If I may, let me drift a bit
with the idea.

When I was a practicing engineer, I read the standard (typically IEEE)
journals.  I also read the trade press -- EDN, Electronic Design, and
others.  Those didn't provide peer-reviewed articles, but they did often
provide newer, shorter, and more practical advice.  Some of it, to be
sure, was funded by vendors eager to sell the latest components or
instruments.  Some were high-quality articles on design techniques (and
some were of lesser quality).  Most trade magazines also had short
"design ideas" sections, typically full of a partial page articles
showing what someone saw as a novel yet simple circuit design to address
some goal.  I think the author would typically get paid $25 to $50 if
their article were published and perhaps another $100 if it were
selected as best of the issue or best of the year.

Even without peer review and with only editorial vetting, you eventually
got to know who was likely to publish better ideas because you often
vetted the articles yourself by trying out the design ideas: those that
didn't work well or where the math didn't support the ideas tended to
fall by the wayside.

EDN and the like were supported solely by advertising, so engineers got
it for free.  Advertisers were willing to sign up, for they could
reasonably expect to see engineers design good components into circuits
and systems, and that would hopefully bring an ongoing revenue stream
that more than made up for the cost of the advertising.  Since our
models don't get implemented in hardware which gets replicated for a
large number of industrial or conusmer customers, it's unlikely we'll
find as many advertisers willing to support such an active trade press.

I think it could be helpful to have such a forum for system dynamicists.
To a degree, this mailing list does that and does it well.  There have
been a number of discussions here about some of the finer points of SD
practice, discussions well worth saving.  

Interestingly, Electronics and Electronic Design used to publish
compendiums of their design ideas from their magazines from time to
time.  Those sound a bit like your idea for a model library.

There are a couple of things that attract me about the design ideas
approach: 

- - It evolves.  It doesn't start life as the set of things we see as
  important today; it starts as a free-flowing stream of things that
  various people find useful.

- - It's not dependent upon one format or vendor.  People would mostly
  submit schematics, but there were some mathematical equations and some
  short program listings.

- - It didn't feel terribly controlled.  You submitted an article, and the
  editors wrote back to say "Thank you, you're accepted," or "Thank you,
  but you're not accepted."  If you were rejected, you could always
  submit it to another magazine, for there were quite a few.

- - It didn't feel as if you were giving up something proprietary.  Things
  that were that short were rarely descriptions of entire systems.  It
  was more likely that they'd describe a nifty, cheap, one-IC SW
  receiver or a small amplifier -- something you could definitely
  consider reusing as part of something else, but nothing you'd likely
  use on its own, at least not for profit.

- - It was eclectic.  What one editorial panel didn't like, another might
  like, so you'd get a variety of ideas that didn't all match.  That was
  perhaps more educational than only seeing great designs (although the
  process usually did seem to generate decent designs).

- - It does serve as a useful reference.  I would clip interesting
  articles from magazines, and I may still have a couple of the
  compendiums stored in a box somewhere.

I could see us sharing more ideas like that here (and I see lots of
challenges).  If we did, I don't think it matters that we use a variety
of different tools.  Most tools seem to have text output that looks
enough like Vensim or like Dynamo so that people can understand the
equations.  I'm perhaps the oddball when I'm using my OSS simulator, but
I bet most of you could follow that code with no problem (you can find
samples on my Web site and in my blog).

What I find hard is figuring out the incentives that would cause a
significant number of us to share those ideas in such a fashion.  In the
engineering case, it was a bit of fame and a bit of cash for a bunch of
engineers who likely didn't know each other.  We're tending to get to
know each other here, so we can get fame by pressing "Send."  In our
case, I'm not sure that 

The field was also more diverse: one engineer might have insights into
using one type of device, and another might have insights into using
another type of device.  We only use stocks and flows :-) -- we don't
specialize very much (at that level).  Are there enough interesting and
useful ways to put 1-4 stocks together (at some size, it turns into a
regular paper) that haven't been covered in the Molecules, in BD or any
of the other standard texts, or in Barry's Intro to Systems Thinking to
keep this flowing?  Perhaps there are.  I guess an experiment is one way
to find out.

Thoughts?  Did I miss the boat entirely on your idea, Bob?

"SDMAIL Bob Eberlein" <bob at vensim.com> writes:

> > That is not to say that Tom Forest's point should be ignored. There is
> > lots of work that would be a lot better if people just applied some of
> > (a bit of or even a gesture toward) the canonical System Dynamics
> > approach. But I think we should encourage people to do that, not
> > exclude them for failing to do so (as long as the have interesting
> > results).

Hear!  Hear!

One of the things I sometimes hear when people express concerns about
the quality of work done in a field (SD or something else) is a desire
to exclude poor work, to prune it out of the standard places, to
regulate or certify it out of existence.

For some reason, I've never thought such an approach to be as useful as
one that encourages better work rather than excises poorer work.
Excluding poor work seems to involve notions of the imposition of power
and of who defines what is good.  It might blow up, as people rebel
against that imposition.  It might succeed at first and then fail later,
as new and useful developments may get quelled because they don't fit
the standard rubric.



Bill
- -- 
Bill Harris             
Facilitated Systems  
Posted by  Bill Harris <bill_harris at facilitatedsystems.com>
posting date  Wed, 20 Feb 2008 19:41:09 -0800