REPLY Who wants to share models (SD6883)

[SDMAIL Tom Fiddaman]

Posted by  Tom Fiddaman <tom at ventanasystems.com>

Posted by  "'richard dudley'" <richard.dudley at attglobal.net>
> Modelwiki looks like a good experiment for sharing models (as opposed to
> the related question of collaborative model building).

Right. One could certainly use a wiki for collaborative model building 
as well (e.g., to keep a running discussion, documentation, and file 
links), but I'm sure better tools could be found. Probably the 
combination of a code management system and a forum would be better (as 
most sourceforge projects have). I'll try to get a colleague to share 
some experience using subversion (SVN) with Vensim text .mdl format 
models. That lets users keep models coordinated and review past changes 
(including who made them).

There have also been some papers on this topic in recent SD conferences. See
http://www.systemdynamics.org/conf2005/proceed/papers/LECLA437.pdf
and
http://www.systemdynamics.org/conferences/2006/proceed/papers/POWEL256.pdf

> Perhaps Tom might give some pointers regarding how we contribute to this.  I
> see several places where I can put information, but I have no guidelines.
> Is there an instant source of information for non-wiki users to get 
> started?

General wiki editing advice is here
http://en.wikipedia.org/wiki/Wikipedia:How_to_edit_a_page

What I know about wikis would make a very short book. However, I found 
it quite easy to create the pages that now exist at 
http://modelwiki.metasd.com

First, you need to register & log in to 
do anything besides browse. As I recall, I allowed self registration 
when I set things up, but if you have trouble, email me.
- Once registered, you can use the Edit tab on any page to modify it. 
You can also browse past changes, see who made them, and undo them if 
you don't like them.
- With respect to editing, I found I only needed to know about 5 things:
* you can organize a page with headers, using = Level 1 = , == Level 2 
== etc.
* you can create pages by simply including the new page name in an 
existing page, e.g. here is a link to a [[new page]] - then following 
the link will give you blank space to create the new page
* you can link to an [[existing page]] the same way
* you can link to [[an external site]] easily as well
* upload images as images; upload models and anything else as media; 
email me if you need a new file type authorized (vensim, powersim, and 
stella/ithink models are possible now)

The trick is for the distributed editing to wind up at a point that's 
reasonably organized. My guess is that the wiki will work as a 
repository for my existing model library. It might also work very well 
as a repository for the molecules, which already have a network 
structure of relationships (i.e., each molecule potentially has parents 
and children and associates). I suspect that it will eventually be 
outgrown as a general model repository though. For that, it would be 
advantageous to have a more structured database, enabling search and 
sorting. For example, one might wish to restrict one's browsing to only 
peer reviewed models in biology having less than 100 equations. However, 
without messing around a bit, I can't anticipate all the fields that 
would be useful in such a respository, so I think the wiki is a good way 
to get started by trying things. For that reason, I was deliberately 
vague about what ought to be done with it.

I think quality will be key. Only including peer reviewed models would 
be one solution, but rather limiting. Instead, I think it would make 
sense to develop the guidelines for submission further, in order to 
discourage submission of low-quality models (e.g. models with obvious 
formulation errors, or missing and unbalanced units). Also, I would 
encourage the use of the wiki text to make comments on models. This may 
be another area where a modelbase with a review and rating system would 
excel at showcasing the best work.

I realize that making this totally open could lead to a mess, but I 
rather doubt that will happen. I'll lock things down if there's an 
explosion of spam pages or some other disaster, but otherwise I'll just 
watch and contribute.

Tom
Posted by  Tom Fiddaman <tom at ventanasystems.com>
posting date  Tue, 08 Apr 2008 17:35:45 -0600