A little economics geekery on topics including the wisdom of crowds, futures markets and group deliberation. I was most interested in the deliberation part, which starts about 25 minutes in.
It’s even worse than garbage in, garbage out in deliberating groups. Typically some garbage in leads to more garbage out. So errors with respect to human cognition are frequently not just propagated in a deliberating group but actually amplified.
Often groups emphasize shared information at the expense of uniquely held information. So if you’re a deliberating group where a bunch of people actually know something, little bits of information that no one else has, those tend to play very little role in the deliberation. And the shared information, what everyone knows, that isn’t dispersed, that has the dominant role.
And this can get groups in big trouble where the uniquely held information, that is crucial, is downplayed or disregarded. And the deliberating group marches happily in the direction indicated by the shared information.
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