Abstract for: Operator confidence in models: comparing two business examples

Forrester (1973, pages 24 & 35) discusses “how operators (people who make decisions to control action) develop confidence in a model’s suitability for purpose. …From the viewpoint of the operator…there is a network of contacts between a model and reality. As the multiple contacts are explored without showing serious discrepancy between a model and the real world it represents, confidence in the model increases.” We describe two modeling projects begun at essentially the same time with shared sponsorship and a shared modeler, but which used different approaches. One approach we name Comparison of Alternative Policies (CAP). The other we name Comparison of Alternative Mental Models of System Structure (CAMMSS). CAP is classical system dynamics; whereas, the CAMMSS approach seems fairly atypical. However, the CAMMSS-developed model is getting significantly more operator interest and referrals than the CAP-developed model. This leads us to believe that operators have more confidence in the CAMMSS-developed model. We explore how the CAMMSS-developed model may provide operators more non-discrepant contacts with their perception of reality, thus creating Forrester’s conditions for more operator confidence. Our origins for CAMMSS lie in Senge’s (1990, 2006, pages 47-51 in both editions) description of how to improve performance in the Beer Game.