Do the Parallel Lines Meet? A Comparison between Pathway Participation Metrics and Eigenvalue Analysis

摘要

The search for tools and techniques aimed at model analysis has gained momentum in the system dynamics community during the last decade. A variety of approaches have been developed, modified and applied to replace or enhance the traditional intuitive-based schemes for understanding the behavior of dynamic models according to its feedback structure. Despite the diversity of the methods developed for model analysis, recent studies suggest that there is considerable convergence in the results they produce. The objective of this paper is to explore some of the similarities and differences between pathway participation metrics and eigenvalue elasticity analysis that can potentially explain the reasons for the convergence and divergence in analysis. In the first part of the paper, we lay out some of the theoretical differences and similarities in approaches between aspects of pathway participation metrics and eigenvalue elasticity analysis in order to explain how they, despite the significant differences in the process of model analysis, can produce similar and comparable results under certain conditions. The second part of the paper presents application of pathway participation metrics in four well-known models that have been previously analyzed using the eigenvalue elasticity approach. The case studies highlight some of the similarities and differences between the two approaches in detecting the dominant structure.