Decision model for complex group argumentation

•Propose a novel decision model for group argumentation under complexities.•Resolve the two-fold complexity derived from the problem and the group in our model.•Evaluate our model to practice supplier selection.•Explore the theoretical and practical development of a classic metasynthesis for complex system designs.

This paper reports on a decision-making model that can be used for group argumentation when decisions contain twofold complexities: the problem itself and the people (i.e., the decision makers). Related studies have been well documented in literature; however, research on the group mechanism remains limited with regard to two aspects: (1) the complexities of problems and people and (2) the interaction manners of opinions derived from people. In this study, we develop a mechanism called the complex group argumentation (CGA) framework for group decision making. This solution applies the classic methodology of system designs, that is, qualitative-to-quantitative metasynthesis, and contains two core processes, namely, complexity resolution and group argumentation. From a practical perspective, we evaluate the performance of the CGA framework in the context of supplier selection (SS). Results show that our approach can satisfy the requirements of practical SS, while simultaneously coping with the disadvantages of real-world complex GDM. The results of this research can inspire studies on group argumentation in academics and provide proposals for mechanisms on the development of group support systems in the industrial community.