Hindsight Bias
JUNE 14, 2010
tags: availability heuristic, hindsight bias, Baruch Fischhoff, Karl Teigen
by David McRaney
The Misconception: After you learn something new, you remember how you were once ignorant or wrong.
The Truth: You often look back on the things you’ve just learned and assume you knew them or believed them all along.
Source: Nick Douglas
“I knew they were going to lose.”
“That’s exactly what I thought was going to happen.”
“I saw this coming.”
“That’s just common sense.”
“I had a feeling you might say that.”
How many times have you said something similar and believed it?
Probably many times, but research shows there is a fundamental flaw in your reasoning.
You tend to edit your memories so you don’t seem like such a dimwit when things happen you couldn’t have predicted. When you learn things you wish you had known all along, you go ahead and assume you did know them. This tendency is just part of being a person, and it is called the Hindsight Bias.
Take a look at the results of this study:
A recent study by researchers at Harvard shows as people grow older they tend to stick to old beliefs and find it difficult to accept conflicting information about topics they are already familiar with. The findings seem to suggest you can’t teach an old dog new tricks.
Of course the study showed this. You’ve known this your whole life; it’s common knowledge.
Consider this study:
A study out of The University of Alberta shows older people, with years of wisdom and a virtual library of facts from decades of exposure to media find it much easier to finish a four-year degree ahead of time than an 18-year-old who has to contend with an unfinished, still-growing brain. The findings show you are never too old to learn.
Wait a second. That seems like common knowledge too.
So which is it – you can’t teach an old dog new tricks, or you are never too old to learn?
Actually, I made both of these up. Neither one is a real study. (Using fake studies is a favorite way of demonstrating hindsight bias, thanks to psychologist David G. Meyers for the idea.)
Both of those fake studies seemed probable because when you learn something new you quickly redact your past so you can feel the comfort of always being right.
In 1986, Karl Teigen, now at the University of Oslo, did a study in which he asked students to evaluate proverbs.
Teigen gave participants famous sayings to evaluate. When participants were given koans like, “You can’t judge a book by its cover,” they tended to agree with the wisdom.
What would you say?
Is it fair to say you can’t judge a book by its cover? From experience, can you remember times when this was true?
What about the expression, “If it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck?” Seems like common sense too, huh?
So which is it?
In Teigen’s study, most people said yes to all the proverbs he showed them, even when they conflicted. When he asked them to evaluate the phrase, “love is stronger than fear,” they agreed with it. When he presented them the opposite, “fear is stronger than love,” they agreed with that too.
He was trying to show how what you think is just common sense usually isn’t. Often, when students and journalists and laypeople hear about the results of scientific study, they say, “Yeah, no shit.”
Teigen showed this is just hindsight bias at work.
Source: Isobel T
You are always looking back at the person you used to be, always reconstructing the story of your life to better match the person you are today.
You have needed to keep a tidy mind to navigate the world ever since you lived in jungles and on savannas. Cluttered minds got bogged down, and the bodies they controlled got eaten.
Once you learn from your mistakes, or replace bad info with good, there isn’t much use in retaining the garbage, so you delete it.
This deletion of your old incorrect assumptions de-clutters your mind. Sure, you are lying to yourself, but it’s for a good cause.
You take all you know about a topic, all you can conjure up on the spot, and construct a mental model. As Baruch Fischhoff at Carnegie Mellon said, this is “good for some things (looking forward with a full set of beliefs), but bad for others (reconstructing previous perspectives).”
Fischhoff was one of the first researchers to pinpoint the mechanisms of hindsight bias. He put together a study right before President Nixon left for China.
He asked people what they thought the chances were for certain things to happen on his trip. Later, once the trip was over, knowing the outcomes, people remembered their statistical assumptions as being far more accurate than they were.
The Washington Post interviewed Fischhoff in 2006, and found him still hard at work exploring the implications of hindsight bias:
“…Americans who made estimates about their danger after the Sept. 11, 2001, attacks recalled having made much lower estimates of risk a year later, after their fears failed to materialize.”
Washington Post, 2006
Hindsight bias is a close relative of the availability heuristic. You tend to believe anecdotes and individual sensational news stories are more representative of the big picture than they are. If you see lots of shark attacks in the news, you think, “Gosh, sharks are out of control.” What you should think is, “Gosh, the news loves to cover shark attacks.”
The availability heuristic shows you make decisions and think thoughts based on the information you have at hand while ignoring all the other information that might be out there.
You do the same thing with Hindsight Bias by thinking thoughts and making decisions based on what you know now, not what you used to know.
“…people’s need to be right is stronger than their ability to be objective.”
N. Crawford, The American Psychological Association
Knowing hindsight bias exists should arm you with healthy skepticism when politicians and businessmen talk about their past decisions.
Also, keep it in mind the next time you get into a debate online or argument with a boyfriend or girlfriend, husband or wife – the other person really does think they were never wrong, and so do you.
