Studies of small groups have shown that deliberation tends to cause polarization. That is, when a group discusses something, its median opinion tends to become stronger in the direction of the median opinion at the beginning of the discusssion.

What it is: in more detail

In more detail, take some group and before they talk, poll everyone about their opinion on an issue, with “0” being a neutral stance, “-10” and “10” being the extremes of one side or another. Now let the group discuss the issue. Afterwards, poll the group again. You will often find that the median opinion has become more extreme in the direction of the original group bias. For example, let’s say the median opinion of the group is 3 to begin with. Maybe it will be 5 after the discussion. The studies that deal with this use issues where the quanitification of opinion is not a problem; either there is a binary decision to be made, or the decision itself is quantifiable (how much funding for some budget, for example). (TODO: add a diagram here)

Perhaps this will be referred to as “inter-group” polarization to distinguish it from the system of “intra-group” polarization where after a discussion some people may be more strongly in one direction whereas other people end up more strongly in another (statistically, an increase in varience of the distribution of opinions).

Sometimes something else happens; an increase in group varience, but a common tendency. For example, if a group had two members, A and B, and A started out at 5 and B started out at -5, and then after a discussion A was at 3 and B was at -9. Intra-group polarization (varience) has increased, but there is a trend in the direction in which the group members opinions has shifted (downwards). (is this desirable? does the direction of the trend indicate the ‘right’ decision to make?) (TODO: diagram)

When it is a problem

Obviously, polarization is troubling; for example, if the conservatives and liberals hang out in small groups of their own kind a lot, one would expect their views to become more polarized, making it harder to acheive consensus across party lines.

When it is not a problem

For binary decisions, it’s inevitable that people that lean towards one answer will lean towards that answer more strongly once they see there is a consensus on it, and those who are against the consensus will not be as secure in their answer when they see there is widespread opposition.

Related factors

In small groups, a push to consensus paradoxically leads to more (intra-group) polarization. This effect is greatest when a binary decision must be made, for example, on a jury. Perhaps the push towards consensus in such a situation actually makes people go into a goal mentality where they feel that they know which decision they want, and they try to acheive that decision.

Further Reading

Steve Rosell (sp?) & Daniel Yankelovich’s book





This is an old discussion, but I just saw this:

Haven’t even read it, beyond the headline.

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