Symbolic and numerical methods in hybrid multi-criteria decision support

Abstract

Abstract During the development of an expert system for regional planning (The Shanxi Province Decision Support System) by IIASA's Advanced Computer Applications (ACA) group, two spatial planning systems evolved. PDAS, a system for the optimization of the industrial structure of an area, which is based on numerical multicriteria optimization techniques; and REPLACE, a site-selection system, implemented in PROLOG, which is based on a qualitative, constraint-satisfaction method. Although both approaches partially overlap, each approach has certain advantages over the other. As a natural extension of the Shanxi DSS, within the framework of a project on Hybrid Decision Support Tools sponsored by the U.S. Bureau of Reclamation, an attempt has been made to integrate the two approaches by developing a hybrid multicriteria alternative selectiion module (HYDAS-HYbrid Discrete Alternative Selection) which will work as a postprocessor for both modules. In HYDAS, artificial intelligence (AI) paradigms and numeric multicriteria optimization techniques are combined to arrive at a hybrid approach to discrete alternative selection. These techniques include: (1) qualitative analysis, (2) various statistical checks and recommendations, (3) robustness and sensitivity analysis, and (4) help for defining acceptable regions for analysis. HYDAS is implemented on high performance workstations using C, PROLOG, and the X graphics library and window system.