REPLY SD Impact on National Government Policies (SD6181)

[System Dynamics Mailing List]

Posted by  Bill Harris <bill_harris at facilitatedsystems.com>

>> The idea that the field has been growing at a rate of 10-20% per year
>> sounded like an old estimate to me, so I decided to look at some actual

Jack,

Of course, there's the question of how to measure growth.  Assuming that
SDS membership is a useful proxy for the number of people doing SD (and
ignoring what "doing SD" means), one could also look on this as a
production function:

                          SD projects
                          done per year          
                            -----                +-------------------+
              ============>(     )==============>| Cumu. SD Projects | 
                            -----                +-------------------+
                            ^   ^-\              
                          /-       ---\
                        /-             ---
                      /-                  projects per
            +--------/----+               member per year
            | SDS Members |
            +-------------+

Thus the size of the field (SD projects done per year) could be the
integral of SDS membership times some constant representing the average
number of projects per person per year.  The number of projects per
person per year may grow over time as people become more proficient
(assuming they can find the need), too.

As I think you noted elsewhere, though, how important is this really?
What's the real problem?  Is it that we see too high a fraction of
governmental decisions being bad (the subject of this thread)?  Then
that's perhaps the major component of the RBP, with SD and other
techniques as potential productivity aids to reduce that stock.

Bill

PS: If anyone is curious, I created the stock and flow diagram using
artist-mode in Emacs.  One can also do text-mode graphs using the dumb
terminal in Gnuplot.
--
Bill Harris                      http://facilitatedsystems.com/weblog/
Facilitated Systems
Posted by  Bill Harris <bill_harris at facilitatedsystems.com>
posting date  Thu, 11 Jan 2007 06:44:49 -0800