18  Improving group decision making

One effective way we could improve group decisions is by replacing groups with models. A second approach is to improve the deliberative process itself.

Below are four example options, although the evidence for their efficacy is mixed.

Role assignment involves giving people discrete roles, such as labelling someone as an “expert”. The purpose is to bring out unshared information by making it clear that the individual expert has a role to play. Stasser et al. (1995) found this to be the case.

Devil’s advocacy is the appointment some group members to deliberately advocate against the group’s inclinations. The research behind devil’s advocates is mixed (Katzenstein (1996)). There is some evidence that devil’s advocacy can be helpful and can enhance group performance but this appears heavily dependent on the particular context. Further, there is less research in organisational contexts outside the lab, which leaves open the question of how the organisational context affects effectiveness. For example, if the dissenter does not genuinely hold the view they are espousing (which is often the case if the role is assigned), can they be effective? Will people discount the dissent accordingly? It may be better for groups to encourage real dissent.

Red teaming is the creation of a team tasked with criticising or defeating the preferred solution or plan. There is some evidence of their value, in areas such as in mock trials and war games (Sunstein and Hastie (2015)), but there is little general evidence that they boost group decision making performance.

The Delphi method was invented at the RAND Corporation to assist analysis during the cold war. It is a process by which you ask people to state their opinions anonymously and independently before deliberation. These opinions are then made available to others. It is effectively a secret ballot plus reasons, and provides a basis for hidden information to emerge without reputational or informational cascades. Several rounds of this process can be held as the group converges on a solution. It’s a great way to flush out doubts and dissent.

Rowe and Wright (2001) reviewed tests of the Delphi method against statistical groups. They found the Delphi groups were superior in 12 of 14 studies.