Against All Odds: Tentative Steps Toward Efficient Information Sharing in Groups (with Darius Schlangenotto & Radovan Vadovic)

Sometimes people vote with little to go on. Sometimes people talk without knowing much. Since they do, it makes sense for others to also vote or talk. Bringing forward all this information, however, can be harmful. It dilutes the voices and votes of those who better understand the issue at hand. Are such groups doomed? Is there hope that they might learn from each other to restrain themselves? Can they achieve this even though they clearly cannot figure it out in a group conversation?

Darius Schlangenotto, Wendelin Schnedler and Radovan Vadovic examine this question in a recent working paper with an experiment. In a large first-year class, teams were formed. Each team was very likely to contain one person who knew whether an urn contained more blue or green balls. All other members only saw one ball from this urn. Whether well-informed or not, all were allowed to vote, either for blue or green, or abstain. Initially, so many people vote that the group's majority picks the correct color only slightly more often than a coin. Had they restrained themselves and abstained, they would have gotten it almost always. Then, people were allowed to talk to their neighbors. Since the neighbors were not in the team, the conversation could not be used to agree on abstention. Nevertheless, the share of those how abstain more than doubled. So even under rather adverse conditions, groups seem to shift toward a better outcome after individual conversations.

For further information