[kepler-dev] Kepler UI- "Boxes and Arrows"

Ferdinando Villa ferdinando.villa at uvm.edu
Sat Jun 19 13:57:28 PDT 2004

Hi Dan - one comment only, linking back to the previous discussion in

In the web page at http://www.nceas.ucsb.edu/~higgins/BoxesAndArrows,
you write this about the Stella version:
>A little thought shows that a Stella model is really a graphical
>representation of a set of coupled rate equations. The net flows
>are just the rates at which stocks increase or decrease. Stella does
>a nice job of hiding these mathematical details, while letting the
>user determine what concepts determine the amount (stocks) of
>various parameters. Note, however, that it would be difficult to use
>Stella models for some other types of workflows - e.g. a set of
sequential image processing steps applied to some scanned image.

Exactly - it would be difficult because Stella is a system dedicated to
creating instances of a very limited ontology - that of stocks, 
flows etc. It's also why the Stella diagram is a lot simpler and more
readable (with limitations) than the others - in fact it contains a
whole new compartment, vegetation, that doesn't even fit in the kepler
window. In fact, Stella is a half-baked conceptual modeling environment.
The "image analysis" ontology could create a Stella-like diagram for
what you mention. And we can do better than Stella!

Also, the strength in Stella is not that the boxes are the "data" as
you mention... the strength is that the boxes are the SPECIES and the
ECOLOGICAL PROCESSES! That's how ecologists see it, and that's why they
like it.

Now - we know SEEK is an ontology-driven system... and we want to
hide the semantic types in the connections. I think your page shows
nicely that we should at least think harder about some kind of
conceptual modeling.

Cheers, ferdinando

On Fri, 2004-06-18 at 17:13, Daniel Higgins wrote:
> Hi All,
>     The recent Kepler thread discussing all sorts of UI issues got me
> thinking about a lot of the issues discussed.  In particular, I liked
> Bertram's characterization of such visual systems as "Boxes and
> Arrows". As a result I put together a personal web page with a number
> of example screen shots from various "Box and Arrow" systems (e.g.
> Stella, Kepler) to try to show similarities and differences. I also
> added some thoughts of my own. If you are interested, see
> http://www.nceas.ucsb.edu/~higgins/BoxesAndArrows/
> Comments are always appreciated.
> Dan Higgins

More information about the Kepler-dev mailing list