REPLY Structural changes and validity (SD6661)

[SDMAIL ybarlas]

Posted by  ybarlas at boun.edu.tr

Hi again,

I received a couple of emails on what I wrote on this topic (that one could
model meta-dynamics of structural changes.  My replies are extensions and
illustrations of George's (Richardson) example on modeling structural changes 
using exponential averages. 

The following more practical clues could be perhaps useful to some
folks interested in modeling such phenomena: 

The key method is to use a 'potential' model structure that is much more
comprehensive/larger than the one needed in any time period. Then one could use
exponentially weighted averages that would gradually phase out some structures
and introduce new ones (with weights that are dynamically determined in time,
some approaching zero while others emerging from zero ).  This, of course, if
we assume that structural changes are not sudden and revolutionary, but rather
evolutionary. In case of sudden structural changes that occur as a result of
critical accumulations, we can use IF THEN ELSE structures. 
 
Examples of such structures exist in models dealing with goal formation. A
recent and comprehensive version(s) can be found in: 

- Barlas Y. and Hakan Ya?arcan. A Comprehensive Model Of Goal Dynamics In
Organizations: Setting, Evaluation And Revision. To appear in Complex Decision
Making: Theory and Practice, Springer, 2007.

- Barlas Y. and Hakan Ya?arcan. Goal setting, evaluation, learning and revision:
A dynamic  Modeling approach. Evaluation and Program Planning. 29(1). 2006. pp
79-87.

all the best,
Yaman Barlas
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Yaman Barlas, Ph.D.              	
Chair,  Industrial Engineering Dept.            
Bogazici University,                  
34342 Bebek, Istanbul, TURKEY              
Posted by  ybarlas at boun.edu.tr
posting date  Mon, 15 Oct 2007 11:26:40 +0300