October 21, 2015
2 Heads Are Better Than 1, Right?
by Dean Harring
Bringing more people into a decision can help -- or hurt. Groups may not only fail to correct individual biases but may amplify them.
Everybody knows that two heads are better than one. We’ve known it since kindergarten, where we were taught that cooperation, collaboration and teamwork are not just socially desirable behaviors-they also help produce better decisions. And while we all know that two or more people working together are more likely to solve a problem or identify an opportunity better than one person doing it alone, it turns out that’s only true sometimes.
Ideally, a group’s collective intelligence, its ability to aggregate and interpret information, has the potential to be greater than the sum of the intelligence of the individual group members. In the 4th century B.C., Aristotle, in Book III of his political philosophy treatise Politics, described it this way: “When there are many who contribute to the process of deliberation, each can bring his share of goodness and moral prudence…Some appreciate one part, some another, and all together appreciate all.”
But that’s not necessarily how it works in all groups, as anyone who has ever served on a committee and witnessed groupthink in action can probably testify.
Groups are as prone to irrational biases as individuals are, and the idea that a group can somehow correct for or cure the individual biases is false, according to Cass Sunstein, Harvard Law School professor and author (with Reid Hastie) of Wiser: Getting Beyond Groupthink to Make Groups Smarter. Interviewed by Sarah Green on the HBR Ideacast in December 2014, Sunstein said that individual biases can lead to mistakes but that “groups are often just as bad as individuals, and sometimes they are even worse.”
Biases can get amplified in groups. According to Sunstein, as group members talk with each other “they make themselves more confident and clear-headed in the biases with which they started.” The result? Groups can quickly get to a place where they have more confidence and conviction about a position than the individuals within the group do. Groups often lock in on that position and resist contrary information or viewpoints.
Researcher Julie A. Minson, co-author (with Jennifer S. Mueller) of The Cost of Collaboration: Why Joint Decision Making Exacerbates Rejection of Outside Information, agrees, suggesting that people who make decisions by working with others are more confident in those decisions and that the process of making a judgment collaboratively rather than individually contributes to “myopic underweighting of external viewpoints.” And even though collaboration can be an expensive, time-consuming process, it is routinely over-utilized in business decision-making simply because many managers believe that if, two heads are better than one, 10 heads must be even better.
Minson disagrees: “Mathematically, you get the biggest bang from the buck going from one decision-maker to two. For each additional person, that benefit drops off in a downward sloping curve.”
Of course, group decision-making isn’t simply a business challenge–our political and judicial systems rely and depend on groups of people such as elected officials and jurors to deliberate and collaborate and make important decisions. Jack Soll and Richard Larrick, in their Scientific American article You Know More than You Think, observed that while crowds are not always wise, they are more likely to be wise when two principles are followed: “The first principle is that groups should be composed of people with knowledge relevant to a topic. The second principle is that the group needs to hold diverse perspectives and bring different knowledge to bear on a topic.”
Cass Sunstein takes it further, saying for a group to operate effectively as a decision-making body (a jury, for instance) it must consist of:
- A diverse pool of people
- Who have different life experiences
- Who are willing to listen to the evidence
- Who are willing to listen to each other
- Who act independently
- Who refuse to be silenced
Does that sound like a typical decision-making group to you? When I heard that description, I immediately thought of Juror 8 (Henry Fonda) in “12 Angry Men”–a principled and courageous character who single-handedly guided his fractious jury to a just verdict. It is much harder for me to imagine our elected officials, or jury pool members, or even the unfortunate folks dragooned into serving on a committee or task force at work, as sharing those same characteristics.
The good news is that two heads are definitely better than one when those heads are equally capable and they communicate freely, at least according to Dr. Bahador Bahrami of the Institute of Cognitive Neuroscience at University College London, author of “Optically Interacting Minds.” He observed: “To come to an optimal joint decision, individuals must share information with each other and, importantly, weigh that information by its reliability.”
Think of your last group decision. Did the group consist of capable, knowledgeable, eager listeners with diverse viewpoints and life experiences, and a shared commitment to evidence-based decision-making and open communication? Probably not, but sub-optimal group behavior and decisions can occur even in the best of groups. In their Harvard Business Review article “Making Dumb Groups Smarter,” Sunstein and Hastie suggest that botched informational signals and reputational pressures are to blame: “Groups err for two main reasons. The first involves informational signals. Naturally enough, people learn from one another; the problem is that groups often go wrong when some members receive incorrect signals from other members. The second involves reputational pressures, which lead people to silence themselves or change their views in order to avoid some penalty-often, merely the disapproval of others. But if those others have special authority or wield power, their disapproval can produce serious personal consequences.”
On the topic of “special authority” interfering with optimal decision-making, I recently heard a clever term used to describe a form of influence that is often at work in a decision making group. The HiPPO (“Highest Paid Person’s Opinion”) effect refers to the unfortunate tendency for lower-paid employees to defer to higher-paid employees in group decision-making situations. Not too surprising, then that the first item on Sunstein and Hastie’s list of things to do to make groups wiser is “Silence the Leader.”
So exactly how do botched informational signals and reputational pressures lead groups into making poor decisions? Sunstein and Hastie again:
- Groups do not merely fail to correct the errors of their members; they amplify them.
- Groups fall victim to cascade effects, as group members follow the statements and actions of those who spoke or acted first.
- They become polarized, taking up positions more extreme than those they held before deliberations.
- They focus on what everybody knows already-and thus don’t take into account critical information that only one or a few people have.
Next time you are on the verge of convening a roomful of people to make a decision, stop and think about what it takes to position any group to make effective decisions. You might be better off taking Julie Minson’s advice, electing to choose just one other person to partner with you to make the decision instead. Seldom Seen Smith, the river guide character in The Monkey Wrench Game by Edward Abbey, was obviously a skeptic when it came to group decision-making, but he may have been on to something when he declared:
“One man alone can be pretty dumb sometimes, but for real bona fide stupidity, there ain’t nothin’ can beat teamwork.”