Selecting a variety of futures for scenario development

Systematic development of future scenarios involves identifying key factors and their different possible values, then selecting combinations of factor values on which to build scenarios. This article recapitulates basic methods of reducing the number of possible combinations of factor values by removing futures containing incompatible factor value pairs, then uses probability and cross-impact measures to further eliminate improbable futures. Working with the remaining plausible futures, the aim is to select a small number of them for scenario development in such a way that there is a balance between the factor values explored. The motivation is to explore possible futures while avoiding unintentional bias by over-representing some factor values and neglecting others. The tool used is a mathematical formulation that is easily solved as an integer linear program. The process is illustrated with a small example.