To figure out whether you'll like the restaurant around the corner or that new guy in accounting or a vacation in Madrid, or just about anything else you've never personally experienced, try asking a stranger who has. That person is more likely to predict more accurately than you your future reaction, according to a new study published in the March 20 issue of Science.
Harvard psychologist Daniel Gilbert, the best-selling author of Stumbling on Happiness, argues that people who try to imagine how much they will like or dislike a future event (a blind date, say) are usually wildly off the mark, and that the most reliable measure of their future response seems to be that of someone who has already experienced the event rather than any actual information about the event itself even if that person is a stranger.
Indeed, Gilbert and his co-authors cite previous research showing people's scant ability to predict their future feelings about most things: "people have been shown to overestimate how unhappy they will be after receiving bad test results, becoming disabled or being denied a promotion, and to overestimate how happy they will be after winning a prize, initiating a romantic relationship or taking revenge against those who have harmed them."
But such is the resistance to this proposition people like to think of themselves as unique, self-aware individuals who can predict their own responses that even after being shown how muddleheaded their own predictions tend to be, people still prefer to rely on them rather than seeking advice from others, Gilbert's study found.
The study, titled "The Surprising Power of Neighborly Advice," included two experiments. In the first, 33 undergraduate women were asked to participate, individually, in a five-minute "speed date" session with a male student. Before her date, each woman was given either "simulation information" (a photograph of the man and a short personal profile that included his name, age, height, hometown and favorite movie, sport, book, song, food and college class) or "surrogation information" (another undergraduate woman's enjoyment rating, on a scale of 1 to 100, of a speed date with the same man). Based on either packet of info, each participant was asked to predict how much she would enjoy her own speed date (in scientific terms, her "affective reaction"); after the actual date, each woman filled out her own score on the 1-to-100 enjoyment scale. It turns out that when women used surrogation info from a fellow student to make their own predictions, they were significantly more in tune with their real-life enjoyment. Compared with browsing a man's photo and profile info, using other female students' opinions of that man "reduced the size of the affective forecasting error by 49%."
"Ironically," the authors write, "84% [of the women] believed that simulation information would allow them to make a more accurate forecast about a future date with a different man."
In the second experiment, students were asked to write a story, which would then be read by a peer and used to classify the writer's personality as Type A, B or C A being positive, B neutral and C being decidedly negative. Type Cs were, for example, said to "sacrifice their beliefs because they seek contentment rather than challenge." Students were also asked to predict how they would feel if their peer judged them to be Type C some participants were asked to predict based on written descriptions of all three personality types; others were not given those descriptions, but shown only a reaction report by a fellow student who previously received a Type C evaluation. Once again, the fellow student's report was a more accurate predictor of students' future feelings than the written personality definitions, reducing the "size of the affective forecasting error by 63%."
Gilbert and his co-authors from Harvard and the University of Virginia say the findings aren't altogether surprising. People all over the world share similar reactions to stimuli; common evolutionary "physiological mechanisms" would explain why people, regardless of culture or belief, generally prefer "warm to cold, satiety to hunger, friends to enemies, winning to losing and so on." The authors write, "An alien who knew all the likes and dislikes of a single human being would know a great deal about the entire species."
Reached on the phone at his office at Harvard, Gilbert said that this new study builds on previous research on psychological biases and fallacies a genre of studies "that show us how we are largely strangers to ourselves." But, he says, we can better understand how we will react to future situations by embracing our commonality with other people, and treating their response to experiences as less subjective than objective.
"What we've done is found a way for people to make highly reliable predictions via a method that they would find preposterous, which is simply to say, 'I'll have what she's having,'" he says.
Of course, it works best when "she" is more like you than not. People may have their own unique preferences, but they also "tend to marry, befriend, work with and live near those who share their preferences and personality traits." So the people we're likely to get "surrogation information" from our neighbors and friends are also more likely to share our likes and dislikes. "There is little disagreement among people about the sources of pleasure and pain," the authors write, "and even less disagreement among neighbors."
Gilbert suggests his research could have some revolutionary implications for the way people behave. For one thing, the next time you sit down at a new restaurant, you might be better off abandoning the menu and instead asking a fellow diner, "What's good here?" Or you might even consider asking friends, family or the village elders whether your partner is marriage material or not. "Most Westeners would reject the notion outright that someone else would pick your marital partner more accurately than you can. It's not clear to me that's true," Gilbert says, conceding that in the case of marriage, the only person who could really help you predict the suitability of a life partner is someone who's already been married to that person too.
Or, maybe not. "That doesn't leave room for changes in character. I'm quite different with my wife than [I was with] my first wife," Gilbert says. "My first wife wouldn't be able to predict very well what my current wife would experience."
After a pause, he corrects himself with a laugh: "You know what, by saying that I'm almost sure I'm falling prey to all these biases. That's the nature of these biases. They don't go away just because you know about them."
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