ABSTRACT
It has been common wisdom over the years that decisions made by groups will be better (or at least less bad) than decisions made by single individuals. Luckily, this common wisdom tends to be correct (Hill, 1982; Kerr & Tindale, 2004). There is now a very large literature demonstrating the “Wisdom of Crowds” (Suroweiki, 2004), or at least the performance advantage of groups over individuals. Thus, the fact that important decisions are often made by groups rather than individuals tends to be good for society and the institutions within which the decisions are made (Davis, 1980). However, there is also evidence that the superiority of groups is not a given (Janis, 1982; Kerr, MacCoun, & Kramer, 1996; Tindale, 1993). In many cases, groups have been shown to make disastrous decisions with deadly consequences (e.g., the Challenger explosion, Bay of Pigs incident, instances of ethnic cleansing, etc.; Forsyth, 2009, Nijstad, 2009; Tindale, Munier, Wasserman, & Smith, 2002). Until recently, the theories used to explain the good decisions and actions of groups have differed from those used to explain the poor decisions and actions. However, recent attempts to identify the basic principles underlying group decision making have begun to show that both good and bad decisions by groups may stem from the same underlying processes (Kerr & Tindale, 2004; Tindale, 2008). These processes, some adapted over many eons of human evolution, have served groups, and their members, well (Kameda & Tindale, 2006; see Van Vugt and Kameda, this volume). However, as human environments have changed, some of these basic processes have led to less than optimal if not disastrous consequences. In situations where the outcomes tend to be negative, these basic processes are not suited to the informational or motivational environment and therefore do not lead to superior performance. Thus, for both good and bad outcomes, the basic group processes remain largely the same, but the environments in which they occur differ in terms of the degree to which such processes are useful.
