Development of decision rationale in complex group decision making

This study explores the characteristics of rationale development in a complex group decision making task and considers design implications for better supporting rationale development in group decision making. Twelve three-person, multi-role teams performed three instances of a collaborative decision making task with physical maps. We used rhetorical structure theory to analyze the structure of their decision making discourse. We found that groups begin their reasoning processing by stating and relating information and finish their reasoning through a point-counterpoint discussion. We also found that established groups reduced their need to analyze information during the last moments of a decision. Implications for the design of group decision support systems to encourage rationale development are presented.