Here is an excerpt from a classic article written by Walter Frick for Harvard Business Review (January 22, 2018). To read the complete article, check out others, sign up for email alerts, and obtain subscription information, please click here.
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To make a good decision, you need to have a sense of two things: how different choices change the likelihood of different outcomes and how desirable each of those outcomes is. In other words, as Ajay Agrawal, Joshua Gans, and Avi Goldfarb have written, decision making requires both prediction and judgment.
But how do you get better at either? We’ve published volumes on this subject —here are a few of my favorites — but there are three rules that stand out. Following them will improve your ability to predict the effects of your choices and assess their desirability.
Rule #1: Be less certain.
Nobel-prize-winning psychologist Daniel Kahneman has said that overconfidence is the bias he’d eliminate first if he had a magic wand. It’s ubiquitous, particularly among men, the wealthy, and even experts. Overconfidence is not a universal phenomenon — it depends on factors including culture and personality — but the chances are good that you’re more confident about each step of the decision-making process than you ought to be.
So, the first rule of decision making is to just be less certain — about everything. Think choice A will lead to outcome B? It’s probably a bit less likely than you believe. Think outcome B is preferable to outcome C? You’re probably too confident about that as well.
Once you accept that you’re overconfident, you can revisit the logic of your decision. What else would you think about if you were less sure that A would cause B, or that B is preferable to C? Have you prepared for a dramatically different outcome than your expected one?
You can also practice aligning your level of your confidence to the chance that you’re correct. Try out quizzes like this one or this one. You’ll realize that while it’s not possible to always be right, it’s totally possible to become less overconfident.
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Here is a direct link to the complete article.