Are Two Heads Better Than One?: An Experimental Analysis of Group vs. Individual Decisionmaking
Two laboratory experiments - one a statistical urn problem, the other a monetary policy experiment - were run to test the commonly-believed hypothesis that groups make decisions more slowly than individuals do. Surprisingly, this turns out not to be true there is no significant difference in average decision lags. Furthermore, and also surprisingly, there is no significant difference in the decision lag when groups decisions are made by majority rule versus when they are made under a unanimity requirement. In addition, group decisions are on average superior to individual decisions. The results are strikingly similar across the two experiments.
Blinder, Alan S. and John Morgan. "Are Two Heads Better Than One? Monetary Policy By Committee," Journal of Money, Credit and Banking, 2005, v37(5,Oct), 789-811.