The Outcome Bias

Andrew O’Connell's brief blog post on HBR this week highlights research by three BYU professors - Lars Lefgren, Brennan Platt, and Joseph Price.   These three economists have written about the outcome bias, an important cognitive bias that impairs our ability to make good decisions.   According to Jonathan Baron and John Hershey, the outcome bias refers to the tendency of people to "take outcomes into account in a way that is irrelevant to the true quality of the decision."   In other words, you should not judge the quality of a decision simply based on an evaluation of the result, yet people do.  You should examine whether a choice was the best possible course of action given the information available at the time, and given the uncertainty in the situation.  Yet, we don't look back at how the decision was made in many cases.  We simply judge the result.  

Professors Lefgren, Platt, and Price explore the outcome bias by looking at the decision-making processes of professional basketball coaches.  These scholars report, "We find they [basketball coaches] are more likely to revise their strategy after a loss than a win—even for narrow losses, which are uninformative about team effectiveness. This increased strategy revision following a loss occurs even when a loss was expected and even when failure is due to factors beyond the team's control."   

Of course, the outcome bias works the other way as well.  How many times do we conclude that we made a good decision simply because a positive result was achieved?   Perhaps the positive outcome occurred despite the fact that made a poor choice.  Perhaps luck played a role.  We tend to downplay those possibilities, and we attribute the good result to our wise choice.  As a Navy Seal once told me, "The minute we forget that luck may have played a role in our most recent success is the minute when we enhance our risk of dying on the next mission."