Design and implementation of desision tree analysis-decision support system ; DETRA-DSS

Abstract

Decision tree analysis is a formal methodology by which complex decision problems can be decomposed into sequences of contemplated decisions (or acts) and their uncertain consequences (or events). The analysis is naturally and conveniently depicted in the form of tree. Main purpose of this research is to build an interactive graphics system for the analysis of decision tree, which we will call DETRA-DSS(DEcision TRee Analysis - Decision Support System). In designing this system, specific interest was concentrated on developing a new dialog method which combines Question/Answer, menu, and input-in-context-of-output. We also added a file management subsystem to store the decision tree for later use. With these dialog and file management subsystem, we can define the required functional capabilities of the system which include some evaluation procedure such as getting EVPI and performing sensitivity analysis. Finally, based on these required functional capabilities, 20 separated programs, which can be independently invoked as the decision process proceeds, are developed and contained in a 5.25" diskette. The system was implemented into IBM PC mainly due to its wide availability and graphics supporting capability. Using DETRA-DSS, a decision maker can construct, modify, store, and evaluate complex decision trees in a very interactive, easy, and flexible way. We believe this system will help to support the decision making process in an uncertain and ambiguous situation.