The value of changing your mind

Decision-Making

With all due respect to the lessons of experience, I prefer the rigor of evidence. When a trio of psychologists conducted a comprehensive review of thirty-three studies, they found that in every one, the majority of answer revisions were from wrong to right. This phenomenon is known as the first-instinct fallacy.

In one demonstration, psychologists counted eraser marks on the exams of more than 1,500 students in Illinois. Only a quarter of the changes were from right to wrong, while half were from wrong to right. I’ve seen it in my own classroom year after year: my students’ final exams have surprisingly few eraser marks, but those who do rethink their first answers rather than staying anchored to them end up improving their scores.

Six months after the decision, the team remembers reaching the final answer immediately. The earlier versions have disappeared from the shared file. On an exam paper, the eraser would at least have left a mark.

The evidence on exam revisions contradicts the folk wisdom that first instincts deserve sacred status. Sometimes the second answer is anxious fiddling. Often it follows from noticing something missed. Order of arrival proves nothing. I want a visible revision point for decisions that can still change. State the current answer and why. Name the evidence that would change it. When new information arrives, record whether it affected the assumptions or merely made somebody uncomfortable. That separates updating from twitching.

The social part matters more than the method. If changing your mind is treated as a confession, people will wait until the evidence becomes humiliatingly overwhelming. Reward someone for moving early on a good signal and the next person may do it before the error gets expensive. You can hear the euphemism already: “I’m not changing the plan; I’m incorporating learning.” Laugh if you like. People can still deliver the revised plan while the proudly consistent group becomes wrong on schedule.

The review begins with version one beside version four. Two changes followed new evidence. One followed a senior opinion. The fourth answer was better, but the team inspects the route there too.