The Condorcet Jury Theorem when Individual Competence is Low

April 23, 2009

The Condorcet Jury Theorem is often cited in support of the thesis that a group is a better truth-tracker than an individual. In other words, suppose there is a group of N people, presented with two options k_1 and k_2 (one of which is true, while the other is false) and the probability of a single member i (i \in N) to make the right choice as to which option is the true one, is > 0.5. When the previous conditions are met, the Condorcet Jury Theorem shows that the larger the size of the group, the higher is the probability of the group to hit the right option.

Several generalizations and relaxations of assumptions have been given (in particular, on the generalizability of the theorem to k options where k>2, see Christian List and Robert E. Goodin 2001) but I haven’t found much literature on the problem when the individual competence in giving the correct answer is <0.5. In particular I have the following observations:

Read the rest of this entry »

5 Comments | Social Epistemology | Permalink
Posted by Carlo Martini

Follow

Get every new post delivered to your Inbox.

Join 35 other followers