Keep it Simple: Dominance Assessment of Short Feedback Loops

Rogelio Oliva
Mays Business School
Texas A&M University
roliva@tamu.edu

Mohammad Mojtahedzadeh
Attune Group, Inc.
mohammad@attunegroup.com


Oliva, R. and Mojtahedzadeh, M., 2004. Keep it Simple: Dominance Assessment of Short Feedback Loops. In Proceedings of the 2004 International System Dynamics Conference. Oxford, UK.


Two approaches have been developed to establish a formal link between system structure and behavior. Eigenvalue elasticity approaches take a system-wide perspective and have been based either on ad-hoc selection of loops (Forrester 1982; Kampmann 1996)--resulting in non-generalizable explanations--or on loops formed by the aggregate paths between state variables (Goncalves et al. 2000)--resulting in low-resolution explanations. The second approach, Pathway Participation Method (PPM) (Mojtahedzadeh et al. 2004), considers pathways as the building blocks of influential structure, but frequently identifies loops as the structure most responsible for an observed behavior. In this study we show, for various models, that the Shortest Independent Loop Set (Oliva 2003) contains the loops identified as most influential by PPM. Since the SILS is structurally derived, and under most circumstances unique, we propose it as a starting point for Kampmann method to derive complete, granular, and generalizable structure-behavior explanations.
Download