• The "cascade effect" or "herding", where group members follow the statements and actions of those who spoke or acted first.
• Polarisation, where members take more extreme positions than those held before deliberations.
• "The common knowledge effect", where information held by all group members has a greater influence on group judgements than information held by one or a few.
The authors concluded that a central goal in group decision-making should be to ensure that groups aggregate the information their members actually have and do not let faulty informational signals and reputational pressures get in the way.
They described several ways to achieve that goal, including:
• Leaders and high-status group members can encourage others to express their own views by refusing to take a firm position at the outset, and indicating a willingness and desire to hear uniquely held information.
• Informing the group that each member has a different and relevant role, or distinctive information to contribute.
• Encouraging authentic dissent or, potentially, appointing a "devil's advocate" or "red team" (for example, to construct a case against a proposal or plan).
• Voting anonymously to insulate group members from reputational pressures and reduce the problem of self-silencing.
• Structuring incentives to reward group success, thereby encouraging information disclosure.
The application of behavioural research to the issue of group performance has important implications for boards. In particular, it demonstrates that board decision-making may be improved by:
• Educating board members on potential individual biases and mental short-cuts, as well as the nature of and reasons for group errors.
• Adopting certain practical safeguards and correctives to help facilitate effective decision-making. The chair will play an important role in this regard.
Henri Eliot is CEO of Board Dynamics.