Everyday Groupthink and Polarisation

Do we think better in groups? Groupthink and group polarisation psychology in action.

personal-875801_640Way back in my first post on cognitive biases I mentioned that a couple of the projects I am working on are quite high pressured, and involve a small, tight knit team. I love working in a small group, and currently our little band is on a roll, producing lots of good research and making some great contacts. For these particular projects, the team is made up of four people, each bringing their own strengths and differing areas of expertise. This sounds like a dream come true right? I’m very lucky, but also quite aware that our small, slightly insulated group brings its own risks, Indeed, the combination of a high pressure environment, a small team and high (in academic terms anyway!) stakes are all characteristics of situations which a psychologist named Janis1 suggest can encourage a phenomena called Groupthink.


Groupthink is defined as situations where groups making decisions can do amazingly badly. The classic example is the ‘Bay of Pigs’ fiasco, where a number of expert military and intelligence chiefs in the US were brought together to come up with a plan to overthrow Castro. The result was an ill-advised scheme. A small number of US backed Cuban revolutionaries were landed on a Cuban beach to try and overthrow Fidel Castro. This was a bad idea. The Cubans knew the forces were on the way, a proposed popular uprising in response to the invasion was banked on despite being objectively unlikely, and there was no air support for the ground forces. The result was a disaster resulting a the loss of a number of lives, the revolutionaries being captured, and a massive PR coup for Castro’s regime.

Why did a number of the US’s chief strategists and tacticians make such a terrible set of decisions? Janis puts it down down to groupthink. Analysis of the decision making processes of this case study (and others) suggests that small, insular decision making groups often overestimate the power and morality of the group (seeing them as invulnerable and morally correct), whilst also becoming closed minded to criticisms (rationalising away criticisms, stereotyping those who oppose them as weak, biased, evil etc). They also become very intolerant of internal dissent and criticism. This is particularly likely to happen when the group is under time-pressure. Combined, these factors can lead to grandiose schemes which are unlikely to succeed being developed, and no-one in the group being willing or able to challenge them. When combined with biases such as optimistic bias and the planning fallacy (see ‘A tale of two biases‘), you can see how groups go wrong.

and polarisation…

One feature common to groupthink (and many other less extreme group situations) is group polarisation. Group polarisation2 is said to occur when a group’s decision becomes more extreme following group discussion than the starting position of the group members attitudes would suggest. For example, everyone in a group is prepared to act a little bit risky. They get together and decide collectively to be very risky. This effect is common and psychologists think that it stems from a combination of processes. When group members exchange information they also increase the number of arguments they have in favour of a given position. They then become more confident in it, and endorse it more extremely. This is known as information influence. Social comparison processes also occur- group members estimate the position of other group members, and attempt to match it. We often overestimate how extreme others opinions are, so become more extreme ourselves. Of course, everyone else does the same, and the process becomes a vicious cycle. We’ve all been here – you sit around, come up with a plan that ‘seemed like a good idea at the time’.

Group work not sounding so attractive now huh? How does this link to my own work? Well, for one, it suggests we need some outside oversight for what we are doing. We hope we have achieved this by appointing a group of volunteers to an ‘Advisory Panel’ who will make suggestions on our work and, in particular, any decisions we make which move us away from our original plans. This may not always be practical for your own work, but having someone you trust to tell you when you are being an idiot and generally keeping an eye on you probably is possible, and if you can manage it you should. We also try and build a group culture where disagreement is encouraged and even valued. This is helped by one or two team members who, although I am very fond of them both, can be described as happy to disagree about anything, anywhere, anytime 😉 )

Ways to avoid Groupthink and polarisation

  1. Encourage disagreement
  2. Have outsiders with no stake in a decision review it if possible
  3. Make sure you note your initial position on an discussion, and check how far you have moved
  4. Work alone (only joking, working in a group makes you productive in other ways, and can be much more fun!)
  5. Have people develop separate ideas then bring them together to compare, this avoids convergence and polarisation.

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  1. Janis, I. L. (1982). Groupthink: Psychological studies of policy decisions and fiascoes (Vol. 349). Boston: Houghton Mifflin. 
  2. Isenberg, D. J. (1986). Group polarization: A critical review and meta-analysis. Journal of Personality and Social Psychology, 50, 1141-1151. 

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