Maintaining Disparities : Analysis with a small evolutionary game model

Abstract

In an earlier System Dynamics Conference, the authors used a small model to illustrate oscillations in local responses to health disparities. It was noted that further work would address medium term trends and thresholds shaping public action to reduce disparities. This paper begins to address those issues using Heckathorn’s model of ‘The Dynamics and Dilemmas of Collective Action’. Among many other things the model illustrates the implications of hypotheses related to the relative ‘fitness’ of voluntary action, reciprocity and sanctions. The hypotheses can be used to explore the concept of governance in a causal loop diagram adopted by the WHO Commission on Social Determinants of Health. The conclusion is that the model (a) provides a framework for analysing elite responses evident in decisions made and avoided by governance groups with duties to promote public health, and (b) has the theoretical depth necessary to be recognised as a ‘canonical situation model’ as proposed by Lane and Smart.