Made to Stick

People often trust their intuition, but our intuition is
flawed by identifiable biases. Still, most people feel pretty good about
their intuition, and it’s hard to convince them otherwise. This is the
uphill battle faced by psychologists who study decision-making. Pre-
tend that you’re the editor of an introductory psychology textbook,
and you’re looking at two competing ways of explaining the concept
of “availability bias.”
• • •
M E S S AG E   1 :  
Get ready to make a few predictions. Which of the follow-
ing events kill more people: Homicide or suicide? Floods or tuber-
culosis? Tornadoes or asthma? Take a second to think about your
answers.
You might have thought that homicide, floods, and tornadoes are
more common. People generally do. But in the United States there
are 50 percent more deaths from suicide than from homicide, nine
times more deaths from tuberculosis than from floods, and eighty
times more deaths from asthma than from tornadoes.
C L I N I C
C R E D I B L E
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So why do people predict badly? Because of the availability bias.
The availability bias is a natural tendency that causes us, when esti-
mating the probability of a particular event, to judge the event’s
probability by its availability in our memory. We intuitively think that
events are more likely when they are easier to remember. But often
the things we remember are not an accurate summary of the world.
We may remember things better because they evoke more emo-
tion, not because they are more frequent. We may remember things
better because the media spend more time covering them (perhaps
because they provide more vivid images), not because they are more
common. The availability bias may lead our intuition astray, prompt-
ing us to treat unusual things as common and unlikely things as
probable.
C O M M E N T S   O N   M E S S AG E   1 :  
This passage uses a simple but effective
testable credential: Which problem do you think kills more people?
With any luck, readers will botch at least one of the predictions, thus
illustrating for themselves the reality of the availability bias.
• • •
M E S S AG E   2 :  
Here’s an alternative passage illustrating the availability
bias that is more typical of introductory textbooks:
The availability bias is a natural tendency that causes us, when
estimating the probability of a particular event, to judge the event’s
probability by its availability in our memory. We intuitively think that
events are more likely when they’re easier to remember. But often the
things we remember are not an accurate summary of the world. For
example, in a study by decision researchers at the University of Ore-
gon, experimental participants thought that 20 percent more people
died in homicides than in suicides, when the truth is that there are 50
percent more deaths from suicides. Subjects thought that more peo-
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M A D E   T O   S T I C K

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ple were killed by floods than tuberculosis, but nine times more peo-
ple are killed by tuberculosis. Subjects believed that approximately as
many people were killed by tornadoes as by asthma, but there are
eighty times more deaths from asthma.
People remember things better because they evoke more emotion,
not because they are more frequent. People remember things better
because the media spend more time covering them (perhaps because
they provide more vivid images), not because they are more common.
The availability bias may lead our intuition astray, prompting us to treat
unusual things as common and unlikely things as probable.
C O M M E N T S   O N   M E S S AG E   2 :  
This is less involving. You could imagine a
student reading the second paragraph—which gives away the punch
line that asthma kills eighty times more people than tornadoes—and
thinking,  Wow, those research participants were dumb. It’s much
more powerful to experience the effect for yourself.
S C O R E C A R D