Abstract:

Individuals often receive others’ advice while making their decisions, and it is an effective way to improve the quality of decision outcomes by integrating outside information into their judgments. In the literature of decision behavior, decision making can be divided into two categories in terms of the number of participants, including individual decision and group decision. The core difference lying between individual decision and group decision is that group decision is made by two or more individuals via information sharing, exchanging, and discussing among group members. Accordingly, previous studies found a significant difference in advice-taking performance between individuals and groups. Based on the multi-stage of the decision process, the main factors causing the above issue include the presence or absence of initial opinion, the confidence for the initial decision, the subjective evaluation towards advice, and the objective feedback of advice. However, although group decision costs more labor, money, and time, joint decision making does not always be able to utilize advice more accurately than individual decision making does. In other words, the jury is still out on whether an individual or group can make better use of external advice.
We propose that group dynamics theory could provide an insightful perspective for understanding the group decision and its difference from an individual decision. Specifically, group dynamics theory suggests that group members are independent and mutually related to each other, and their interactions constitute a group dynamics system involving cohesive force, driving force, and dissipative force. First, cohesive force binds members as a whole, such that groups which appear to be coherent and unified are more likely to display prejudice toward external opinions and advice because of the high confidence and the desire of maintaining group stability; Second, driving force serves as a motivative factor that directs members to be more involved and endorsed in the decision process, which is beneficial to the sustainable development of the group. That is, group members motivated by driving force tend to express and exchange more information about decision tasks as well as adopt a systemic approach instead of a heuristic approach to process external advice, thereby, a group with high driving force may result in greater performance by taking advice; Third, negative factors within groups would undermine members proactivity and group effectiveness, manifesting as dissipative force, which may cause biased cognition and negative emotion of members, as a consequence, hindering group performance in decision behavior. Taken together, these three forces interact, complement, and restrict each other during the group decision making process, in turn, influencing group advice-taking. We argue that the significant distinction in advice-taking behavior between individuals and groups can be partly derived from this kind of dynamics system. Therefore, understanding the changes among cohesive force, driving force, and dissipative force within a group could help us explain and predict group behavior in decision making. 
To date, advice-taking at the individual level has been caught a lot of attention, whereas research on group advice-taking is still in its early stages and needs to be further investigated, meanwhile, there is also an urgent call for developing the corresponding theory, method, and measurement for the group decision. According to the group dynamics theory, future research can explore the effect of the nature of groups on advice-taking, including both objective construct (e.g. the optimal number of participants in decision making) and subjective construct (e.g. social status or power between participants). In addition, it is also worth noted that whether the way of interaction would impact the group dynamics system and its subsequent advice-taking behavior, such as interactive mediums and rules, communicative atmosphere. Moreover, despite advice-taking behavior, there are a lot of other issues in the decision process that could be addressed from the perspective of group dynamics theory, such as group thinking, shared information bias, and self-other decision. 

Key words: decision making, individual advice taking, group advice-taking, group dynamics theory