Human Stupidity: Historical: Group Reasoning III

It is not always true that groups always outperform individuals, though. Comparisons between the estimates of a group and those of the best informed individual in the same group did not provide such a clear cut answer. In that case, the results of the experiments were not consistent between different problems. Sometimes the groups were able to provide better results than their most competent member, while, under different circumstances, the best member was capable of outperform the group.




As a matter of fact, Kerr et al.  concluded there is no simple answer to the question of whether individuals or groups are more biased. Both gains and losses have been observed as consequence of obtaining the opinion of groups. Different circumstances on how the group interact can make a significant difference on the outcome as well as the type of question or task proposed. The number of papers on the subject is quite large and, here, I will just comment on a few cases where problems have been observed. The cases I will describe are very far from exhaustive and no claim about importance is made.


A classical case of group decisions going wrong is the circumstance coined by Irving Janis as groupthink in Victims of Groupthink: A psychological study of foreign-policy decisions and fiascoes. Groupthink is what happens when the desire to conform and agree with others is such that it interferes with critical thinking. In those situations, people might adopt some idea that they believe better conform to the group norms, instead of actually providing their best independent evaluation. This can happen in a variety of circumstances, from groups with a strong sense of belonging (sport fans or religious communities, for example), to cases where one opinions have a strong moral value attached to them or when people simply want to show support for a leader (for example, their boss).



What is particularly troublesome about groupthink is that, when it is observed, it is not just the case that the group makes decisions that are worse than its most competent member. It can actually happen that the group will reason in ways that are much worse than the average individual of the group would. Examples of this can be often observed in the behavior of crowds in sport events, where insults and violence happen far more often than it would be reasonable to expect if those same people were deciding as individuals.

Human Stupidity: Historical: Group Reasoning II

Group decisions happen every day. We choose the people who will represent us in the government (in several countries, at least), we participate in groups of different sizes that have to reach an agreement about how to act (assuming a collective action does happen). Sometimes a group decision can be described as the sum of mostly independent decisions and actions, taken individually, as in an election. At other times, we assemble and discuss and the final estimate or the final action is decided as a result of the social process that happens between the assembled people. And, under different circumstances, a society may move in a direction that is just the consequence of how many individual actions interact with each other, with no real sense of group decision, except as a consequence of the sum of the behaviors and their interactions. One example of this is the fluctuation of prices as a consequence of the individual decisions of buyers and sellers. In this last case, all reasoning can be described as individual reasoning, while in the first two, decisions are made as a consequence of the sum of the opinions and, sometimes, the interactions between those opinions.


While the case of how the actions of people can influence the decision of the societies as a whole is very interesting (and I will return to it farther ahead), when we talk about the reasoning of a group, this is usually understood to be the first two cases. At this point, we will just discuss the cases where some reasoning is expected from the group, with or without interaction between its members.


After so many disappointments on our individual abilities, it makes sense to start with some good news. More than a hundred years ago, during the West of England Fat Stock and Poultry Exhibition, Francis Galton observed a contest where people attempted to provide the best guess for the weight of a fat ox . Of course, people proposed a range of different values, some close and some very distant from the true value (1,198 pounds). What surprised Galton was the fact that the median of the guesses was actually very close to the correct value at 1207 pounds. Later, he reported the average of the guesses was even closer to the real value, at 1,197 pounds!


This effect, where some average estimate provided by a group of people shows a remarkable agreement with reality was later coined as the Wisdom of Crowds. Galton associated this with the strength of a democratic government, where decisions arise from some kind of averaging over the opinions of many. Of course, the observation of one single case of a group estimate was not enough for a conclusion and several experiments were performed to test how well groups perform. In a 1982 review, Gayle Hill discusses the case of several papers published since Galton's initial observation. In her review, Gayle presented four different comparisons (in all cases, the results for groups included both groups working independently as well as groups where people were allowed to interact with each other): groups versus individuals, groups versus the most competent member, groups versus statistically pooled responses, and groups versus mathematical models. What she concluded from reviewing previous work was that, in the case of groups versus individuals, the groups tended to perform better, as expected. So, what happens when we examine the other possibilities (as well as other possible effects)?

Human Stupidity: Historical: Group Reasoning

It should be clear by now that we should be very careful with any information our minds present to us. While our brains do a good job most of the time, they can easily be fooled and, depending on the circumstances, will fool themselves with no exterior help needed. As I have pointed before, this seems to conflict with all the amazing achievements we, as a species, were able to accomplish.

One possible explanation for this might be in that very phrase. We have accomplished as a species far more than any individual could. Even our greatest genius were able to do their work thanks to the many man who came before them (Newton's claim that he only saw further because he was standing on the shoulders of giants is so well known it has became a common place), in great disagreement with the descriptions of scientists in fictional works. The super genius who can understand anything fast has never existed outside comic books and other sources of entertainment. This suggests that, while we do lack something as individuals, it might be possible that our combined brain powers were responsible for all the advances and explanations we have created.

And, indeed, when observing human history, this seems to be the case. Each scientist contributed with a new piece to the large puzzle, some with larger pieces, some with smaller ones. But many of those pieces only made sense in the context of the knowledge society had at the time. We have new methods of preserving old knowledge. First, for whatever adaptive reason, our ancestors developed our language skills to a level not observed until now in any other species. Later we created ways to preserve that knowledge in permanent materials, through writing and several other information preserving technologies. And we are still creating new ways to do that today. It might seem that while we can be quite flawed as individuals, maybe mankind is much more capable than we are as humans.

This poses a question that deserves a new dive into the literature of psychological experiments: Are group of people better at reasoning and deciding than the individuals? If so, are they always better or that improvement only happens under some conditions?