Contagious Why Things Catch On

immediate word of mouth.
This occurs when
you pass on the details of an experience, or share new information you’ve acquired, soon after it
occurs.
Ongoing word of mouth
, in contrast, covers the conversations you have in the weeks and months
that follow. The movies you saw last month or a vacation you took last year.
Both types of word of mouth are valuable, but certain types are more important for certain products
or ideas. Movies depend on immediate word of mouth. Theaters are looking for success right off the
bat, so if a film isn’t doing well right away, they’ll replace it with something else. New food products
are under similar pressure. Grocery stores have limited shelf space. If consumers don’t immediately
start buying a new anticholesterol spread, the store may stop stocking it. In such cases, immediate
word of mouth is critical.
For most products or ideas, however, ongoing word of mouth is also important. Antibullying
campaigns not only want to get students talking right after the campaign is introduced, they want them
to keep spreading the word until bullying is eradicated. New policy initiatives certainly benefit from
huge discussion when they are proposed, but to sway voter opinion, people need to keep mentioning
them all the way up until Election Day.
But what leads someone to talk about something soon after it occurs? And are these the same things
that drive them to keep talking about it for weeks or months after?
To answer these questions, we divided the data on each BzzCampaign into two categories:
immediate and ongoing word of mouth. Then we looked at how much of each type of buzz different
types of products generated.
As we suspected, interesting products received more immediate word of mouth than boring
products. This reinforces what we talked about in the Social Currency chapter: interesting things are
entertaining and reflect positively on the person talking about them.
But interesting products did not 
sustain
high levels of word-of-mouth activity over time. Interesting
products didn’t get any more ongoing word of mouth than boring ones.
Imagine I walked into work one day dressed as a pirate. A bright red satin bandana, long black
waistcoat, gold earrings, and a patch over one eye. It would be pretty remarkable. People in my office
would probably gossip about it all day. (“What in the world is Jonah doing? Casual Friday is
supposed to be relaxed, but this is taking it too far!”)
But while my pirate getup would get lots of immediate word of mouth, people probably wouldn’t
keep talking about it every week for the next two months.
So if interest doesn’t drive ongoing word of mouth, what does? What keeps people talking?

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FROM MARS BARS TO VOTING: HOW TRIGGERS AFFECT BEHAVIOR
At any given moment, some thoughts are more top of mind, or accessible, than others. Right now, for
example, you might be thinking about the sentence you are reading or the sandwich you had for lunch.
Some things are chronically accessible. Sports fanatics or foodies will often have those subjects
top of mind. They are constantly thinking of their favorite team’s latest stats, or about ways to
combine ingredients in tasty dishes.
But stimuli in the surrounding environment can also determine which thoughts and ideas are top of
mind. If you see a puppy while jogging in the park, you might remember that you’ve always wanted to
adopt a dog. If you smell Chinese food while walking past the corner noodle shop, you might start
thinking about what to order for lunch. Or if you hear an advertisement for Coke, you might remember
that you ran out of soda last night. Sights, smells, and sounds can 
trigger
related thoughts and ideas,
making them more top of mind. A hot day might trigger thoughts about climate change. Seeing a sandy
beach in a travel magazine might trigger thoughts of Corona beer.
Using a product is a strong trigger. Most people drink milk more often than grape juice, so milk is
top of mind more often. But triggers can also be indirect. Seeing a jar of peanut butter not only
triggers us to think about peanut butter, it also makes us think about its frequent partner, jelly. Triggers
are like little environmental reminders for related concepts and ideas.
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Why does it matter if particular thoughts or ideas are top of mind? Because accessible thoughts and
ideas lead to 
action.
Back in mid-1997, the candy company Mars noticed an unexpected uptick in sales of its Mars bar.
The company was surprised because it hadn’t changed its marketing in any way. It wasn’t spending
additional money on advertising, it hadn’t changed its pricing, and it hadn’t run any special
promotions. Yet sales had gone up. What had happened?
NASA had happened. Specifically, NASA’s Pathfinder mission.
The mission was designed to collect samples of atmosphere, climate, and soil from a nearby
planet. The undertaking took years of preparation and millions of dollars in funding. When the lander
finally touched down on the alien landscape, the entire world was rapt, and all news outlets featured
NASA’s triumph.
Pathfinder’s destination? Mars.
Mars bars are named after the company’s founder, Franklin Mars, not the planet. But the media
attention the planet received acted as a trigger that reminded people of the candy and increased sales.
Perhaps the makers of Sunny Delight should encourage NASA to explore the sun.
Music researchers Adrian North, David Hargreaves, and Jennifer McKendrick examined how
triggers might affect supermarket buying behavior more broadly. You know the Muzak you’re used to
hearing while you shop for groceries? Well, North, Hargreaves, and McKendrick subtly replaced it
with music from different countries. Some days they played French music while other days they
played German music—what you’d expect to hear outside a French café on the banks of the Seine and
what you might expect to hear at Oktoberfest. Then they measured the type of wine people purchased.
When French music was playing, most customers bought French wine. When German music was
playing most customers bought German wine. By triggering consumers to think of different countries,
the music affected sales. The music made ideas related to those countries more accessible, and those
accessible ideas spilled over to affect behavior.
Psychologist Gráinne Fitzsimons and I conducted a related study on how to encourage people to eat

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more fruits and vegetables. Promoting healthy eating habits is tough. Most people realize they should
eat more fruits and vegetables. Most people will even say that they 
mean
to eat more fruits and
vegetables. But somehow when the time comes to put fruits and vegetables into shopping carts or onto
dinner plates, people forget. We thought we’d use triggers to help them remember.
Students were paid twenty dollars to report what they ate every day for breakfast, lunch, and dinner
at their nearby dining hall. Monday: a bowl of Frosted Flakes cereal, two helpings of turkey lasagna
with a side salad, and a pulled pork sandwich with spinach and fries. Tuesday: yogurt with fruit and
walnuts, pepperoni pizza with Sprite, and shrimp pad thai.
Halfway through the two weeks we’d designated for the study, the students were asked to
participate in what seemed like an unrelated experiment from a different researcher. They were asked
to provide feedback on a public-health slogan targeting college students. Just to be sure they
remembered the slogan, they were shown it more than twenty times, printed in different colors and
fonts.
One group of students saw the slogan “Live the healthy way, eat five fruits and veggies a day.”
Another group saw “Each and every dining-hall tray needs five fruits and veggies a day.” Both
slogans encouraged people to eat fruits and vegetables, but the tray slogan did so using a trigger. The
students lived on campus, and many of them ate in dining halls that used trays. So we wanted to see if
we could trigger healthy eating behavior by using the dining room tray to remind students of the
slogan.
Our students didn’t care for the tray slogan. They called it “corny” and rated it as less than half as
attractive as the more generic “live healthy” slogan. Further, when asked whether the slogan would
influence their own fruit and vegetable consumption, the students who had been shown the “tray”
slogan were significantly more likely to say no.
But when it came to actual behavior, the effects were striking. Students who had been shown the
more generic “live healthy” slogan didn’t change their eating habits. But students who had seen the
“tray” slogan and used trays in their cafeterias markedly changed their behavior. The trays reminded
them of the slogan and they ate 25 percent more fruits and vegetables as a result. The trigger worked.
We were pretty excited by the results. Getting college students to do anything—let alone eat more
fruits and vegetables—is an impressive feat.
But when a colleague of ours heard about the study he wondered whether triggers would impact an
even more consequential behavior: voting.
—————
Where did you cast your ballot in the last election?
Most people will answer this question with the name of their city or state. Evanston. Birmingham.
Florida. Nevada. If asked to clarify, they might add “near my office” or “across from the
supermarket.” Few will be more specific. And why should they be? Although geography clearly
matters in voting—the East Coast leans Democratic while the South skews Republican—few people
would think that the exact venue in which they vote matters.
But it does.
Political scientists usually assume that voting is based on rational and stable preferences: people
possess core beliefs and weigh costs and benefits when deciding how to vote. If we care about the
environment, we vote for candidates who promise to protect natural resources. If we’re concerned
about health care, we support initiatives to make it more affordable and available to greater numbers
of people. In this calculating, cognitive model of voting behavior, the particular kind of building

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people happen to cast their ballot in shouldn’t affect behavior.
But in light of what we were learning about triggers, we weren’t so sure. Most people in the United
States are assigned to vote at a particular polling location. They are typically public buildings—
firehouses, courthouses, or schools—but can also be churches, private office buildings, or other
venues.
Different locations contain different triggers. Churches are filled with religious imagery, which
might remind people of church doctrine. Schools are filled with lockers, desks, and chalkboards,
which might remind people of children or early educational experiences. And once these thoughts are
triggered, they might change behavior.
Could voting in a church lead people to think more negatively about abortion or gay marriage?
Could voting in a school lead people to support education funding?
To test this idea, Marc Meredith, Christian Wheeler, and I acquired data from each polling place in
Arizona’s 2000 general election. We used the name and address of each polling location to determine
whether it was a church, a school, or some other type of building. Forty percent of people were
assigned to vote in churches, 26 percent in schools, 10 percent in community centers, and the rest in a
mix of apartment buildings, golf courses, and even RV parks.
Then we examined whether people voted differently at different types of polling places. In
particular, we focused on a ballot initiative that proposed raising the sales tax from 5.0 percent to 5.6
percent to support public schools. This initiative had been hotly debated, with good arguments on
both sides. Most people support education but few people enjoy paying more taxes. It was a tough
decision.
If where people voted didn’t matter, then the percent supporting the initiative should be the same at
schools and other polling locations.
But it wasn’t. More than ten thousand more people voted in favor of the school funding initiative
when the polling place was a school. Polling location had a dramatic impact on voting behavior.
And the initiative passed.
This difference persisted even after we controlled for things like regional differences in political
preferences and demographics. We even compared two similar groups of voters to double-check our
findings. People who lived near schools and were assigned to vote at one versus people who lived
near schools but were assigned to vote at a different type of polling place (such as a firehouse). A
significantly higher percentage of the people who voted in schools were in favor of increasing
funding for schools. The fact that they were 
in
a school when they voted triggered more school-
friendly behavior.
A ten-thousand-vote difference in a statewide election might not seem like much. But it was more
than enough to shift a close election. In the 2000 presidential election the difference between George
Bush and Al Gore came down to less than 1,000 votes. If 1,000 votes is enough to shift an election,
10,000 certainly could. Triggers matter.
So how do triggers help determine whether products and ideas catch on?
SEARCHING FOR “FRIDAY” ON . . . FRIDAY
In 2011, Rebecca Black accomplished a momentous achievement. The thirteen-year-old released
what many music critics dubbed the worst song ever.
Born in 1997, Rebecca was just a kid when she released her first full-length song. But this was far
from her first foray into music. She had auditioned for shows, had attended music summer camp, and

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had sung publicly for a number of years. After hearing from a classmate who had turned to outside
help for her music career, Rebecca’s parents paid four thousand dollars to ARK Music Factory, a Los
Angeles label, to write a song for their daughter to sing.
The result was decidedly, well, awful. Entitled “Friday,” the tune was a whiny, overproduced
number about teenage life and the joys of the weekend. The song starts with her getting up in the
morning and getting ready to go to school: