REPLY SD Impact on National Government Policies (SD6170)

[System Dynamics Mailing List]

Posted by  "Jack Homer" <jhomer at comcast.net>

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 
data.  Thanks to Roberta Spencer for the raw data; any errors in 
calculation of average growth rates (AGR) below are mine alone.

SD Society Membership:
Global: 1985-167, 1996-572, 2000-946, 2005-1052;  AGR 85-05: 9.6%, 
AGR 85-96: 11.8%, AGR 96-05: 7.0%, AGR 00-05: 2.1%

North America: 1996-315, 2000-422, 2005-485; AGR 96-05: 4.9%, 
AGR 00-05: 2.8%

Europe: 1996-160, 2000-358, 2005-373; AGR 96-05: 9.9%, 
AGR 00-05: 0.8%

Rest of World: 1996-97, 2000-166, 2005-194; AGR 96-05: 8.0%, 
AGR 00-05: 3.2%

ISDC Attendance (selecting only North America East Coast conferences for 
consistency):
1990 Boston-191, 1996 Boston-275, 1998 Quebec-331, 2001 Atlanta-352, 
2003 NYC-460, 2005 Boston-521.  AGR 90-05: 6.9%, AGR 98-05: 6.4%.

Conclusion: Although we may have grown at that 10-20% rate in the more 
distant past, we have grown at only single-digit rates, and in decelerating 
fashion, since the 1990s.  (Society membership and conference attendance seem 
like reasonably good gauges for size of the field.  If anyone has other 
relevant and available time series, those would be interesting to see.)

In SD, we pride ourselves at looking squarely at the facts and not trying to 
gloss them over with wishful thinking.  Can't we just get over the notion that 
we're going to have big numbers someday?  Let's buckle down to do what a small 
field must do if it is to succeed: Stop tilting at windmills on our own, and 
work and publish collaboratively with people from other fields, esp. experts in 
application areas.

Jack Homer 
Posted by  "Jack Homer" <jhomer at comcast.net>
posting date  Tue, 9 Jan 2007 13:25:33 -0500