Don’t Be Mean! We Regress to the Mean With or Without Scolding.

Posted on February 20, 2015


Thinking-Fast-and-Slow-CoverYou’ve probably had this experience, and made the very same mistake that most people make.

You perform a task exceptionally well, compliment yourself for a job well done, and then notice your next attempt at the very same task is much less effective. Compliments, you decide, affect your performance for the worse!

On the other hand, you’ve probably had the opposite experience, too. You do something very poorly, scold yourself for your poor performance, and then notice that your next attempt at the same task has improved. Aha! A good scolding, you decide, affects your performance for the better!

Before you know it, you’re trying not to jinx yourself with compliments and cursing at yourself like a drill sergeant whenever you make a mistake.

Unfortunately, your assessment of what’s happening is totally wrong! Rewarding improvements in performance is always more effective in the long run than punishing mistakes — no matter what your experience seems to suggest!

What’s happening is that your brain’s instinctive desire to make sense of the world around you, quickly and easily, is overlooking the statistical phenomenon known as regression to mean.

The key factor in your misunderstanding of the situation is the exceptionally good or poor performance that prompts you to compliment or berate yourself. Whenever you deviate exceptionally from normal performance, the next time you undertake the very same task, you’re much more likely to perform at levels more typical for you — that is closer to your average or mean performance.

This will almost always happen whether you compliment yourself or not! Perform a task exceptionally well, and you can expect the next attempt to be less successful and closer to your mean. Perform a task very poorly, and you can expect your very next attempt to be better and closer to your mean performance.

Your brain, unfortunately, isn’t a statistician by nature, and its love of easy answers makes it hard for you to resist your hunch that compliments jinx and scolding improves performance simply because you’re much more likely to compliment exceptional performance and scold its very poor cousin.

Useful nuggets like our tendency to misunderstand the role of regression to mean are found throughout Thinking, Fast and Slow, written by Nobel Prize winner, Daniel Kahneman, who won the Nobel Prize for Economics and, unfortunately, not for Literature. It may seem like a cheap shot, but I doubt this book would have gone to press in its present form, if its author didn’t have the highly marketable stamp of approval from the Nobel committee.

Thinking, Fast and Slow, is a hard slog of a read, and, in places, downright crippling. Not because the subject matter it covers is necessarily difficult or esoteric but because it’s not terribly well written. It’s tone and style varies so much, it’s difficult to understand even who this book is intended for. At times, it’s far too detailed and academic for the casual reader, but, because it’s ultimately a rehash of well-known and widely accepted research, I doubt any experts in the field will want to read it just to discover the personal anecdote Kahneman uses to explain the common mistake I described at the outset.

I can’t recommend Thinking, Fast and Slow, especially when there are many well-written books that cover the same ground. If you’re interested in learning more about the relationship between the conscious and unconscious systems of the brain, start with Strangers to Ourselves by Timothy D. Wilson.  If you want to learn more about the ineffective shortcuts our brain often makes when reasoning, I’d start with You Are Not So Smart or You Are Now Less Dumb by David McRaney. Or check out his site.

If you want to explore and discuss in greater detail the ideas and research in these books, I can help.

Posted in: Thinking