Subject: Feedback Loops

Posted by Phil Minnaar on 2/7/2006
In Reply To:Feedback Loops Posted by Jay W. Forrester on 2/7/2006

Message:

Dear Prof Forrester,

I venture to say that the word "loop" implies a series of variables in which a change in the first variable causes a change in the next variable, which then causes a change in the next variable and so on and that the last variable in the series then causes a change in the first variable, thereby closing the feedback loop.

In the case of a lightning flash the temperature of the molecules in the air is changed to an exceedingly high level. The heat is dissipated in all directions throughout the surrounding molecules with smaller and smaller changes in temperature outwards. The temperature of the molecules eventually return to normal but I do not see the feedback loop to the original overheated molecules in this case.

Another case: In drawing causal loop diagrams one searches for those balancing loops and reinforcing loops by following a possible path through the variables and many times reaches a dead end.

Another case: In an organization a department can function, causing a lot of changes in many things, but without control from Top Management because of a lack of feedback.

Am I missing something? Please help.

Phil Minnaar

Follow Ups:

Feedback Loops - John Sterman 2/8/2006