The role of multidirectional temporal analysis in scenario planning exercises and Planning Support Systems

Planning Support Systems (PSSs) have advanced the process of scenario planning by anticipating potential future outcomes to specific scenario stimulus or investment choices. The models used in these PSSs have typically been restricted to forward-looking exercises, limiting the depth and breadth of understanding of particular problem sets. In this paper we argue that PSS-based scenario planning processes and outcomes might be improved by including multi-directional temporal analysis. This includes alternative timeline navigation methods such as backcasting, recasting, and pastcasting, along with traditional (forward looking) forecasting. These methods can greatly improve the general understanding of modeled results by providing an ability to more deeply inspect the potential consequences of proposed scenarios. We demonstrate these benefits using an application of University of Illinois' Land-use Evolution and impact Assessment Model (LEAM) in McHenry County, IL. In this study, multi-directional techniques were used to analyze the results of LEAM simulation scenarios in terms of actual county spatial and population distributions. Possible issues of variable co-linearity and error attribution were addressed along with a method for improving explanatory power through parameter shrinkage. Based on analysis, we discuss how the ability to navigate through timelines can augment scenario planning processes and help guide strategic sustainable development.