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The dangers of deliberation: suppressing rather than amplifying hidden knowledge

by Michael Nielsen on November 6, 2008

Continuing yesterday’s theme, Cass Sunstein’s “Infotopia” provides a remarkable example of the things that can go wrong when groups collaborate. From an experiment in simulated elections:

Information was parceled out to group members about three candidates for political office; if the information had been properly pooled, the group would have selected Candidate A, who was clearly the best choice. The experiment involved two conditions. In the first condition, each member of the four-person group was given most of the relevant information (66 percent of the information about each candidate). In that condition, 67 percent of the group members favored Candidate A before discussion, and 85 percent after discussion…

In the second condition, by contrast, the information that favored Candidate A was parceled out to various members of the group, rather than shared by all. As this condition was designed, the shared information favoured the two unambiguously inferior candidates, B and C. If the unshared information emerged through discussion and was taken seriously, Candidate A would be chosen.

In that condition, fewer than 25 percent of group members favored Candidate A before discussions, a natural product of the initial distribution of information. But (and this is the key result) the number of people favoring Candidate A actually fell after discussion, simply because the shared information had disproportionate influence on group members. In other words, groups did worse, not better, than individuals when the key information was not initially shared by group members. The commonly held information was far more influential than the unshared information, to the detriment of the group’s ultimate decision.

Sunstein gives many similar examples where groups behave worse than individuals; all failures of collective cognition. Of course, the examples are of limited import, because he’s talking about groups using rather unstructured processes. With good facilitation, good process, or simply good tools, many of these collective cognitive biases can likely be avoided.

  1. have to look at collective consciousness to get a handle on this .. not the brain, not the mind, but the way awareness works, through the subtle bodies .. then it is perfectly understood … ask any yogi

  2. Hi, Michael.

    I’ve found your blog recently while generally searching for more perspectives on scientific publication…a ref librarian friend and I sent several blog posts from a few different sites as a form of “discussion”. As a result, I’ll begin incorporating many of your posts into an advanced undergrad class I teach — I’m very much looking forward to discussing the changing publication landscape with those who will be likely participants! I’m also going to structure their experience with some of the sharing platforms to see if “ambient intimacy” as a concept has an analogue in “ambient literacy” — it ought to be fun!

    An interesting application of “collective intelligence” is the SWoRD program out of of the University of Pittsburgh —
    I haven’t tried it in classes yet b/c of the time required, but seems like an interesting statement regarding the power of collaborative input compared to the individual comment of an expert.

    The SWoRD home page is under construction, with plans apparently to re-emerge as “consilience” — a concept I remember reading at an airport bookstore many years ago:), but only have a vague recollection of meaning something to do with collective knowledge. I wonder about the change of name since consilience as a topic then didn’t seem to take off. Still, I’ve read the studies the Pitt team has done, and the conclusions are provocative, especially since “peer review” at the undergrad level is usually unproductive, even as a training into the concept at higher levels.


  3. Mickey – I’m very glad to hear you find the work useful, and hope your undergrads get something out of it. I’d never heard of “ambient intimacy” before, and have been Googling around; it’s fascinating. Thanks also for the pointer to SWoRD, which I’ll check out.

    Consilience was, I think, revived by E. O. Wilson’s book of the same name a few years ago. I enjoyed it a great deal, enough that my first book (authored with Ike Chuang) opens with a quote from Consilience.

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