Predictably Irrational: The Hidden Forces That Shape Our Decisions

by Dan Ariely

humans rarely choose things in absolute terms. We don’t have an internal value meter that tells us how much things are worth. Rather, we focus on the relative advantage of one thing over another, and estimate value accordingly.

most people don’t know what they want unless they see it in context.

We don’t know what kind of racing bike we want—until we see a champ in the Tour de France ratcheting the gears on a particular model. We don’t know what kind of speaker system we like—until we hear a set of speakers that sounds better than the previous one. We don’t even know what we want to do with our lives—until we find a relative or a friend who is doing just what we think we should be doing. Everything is relative, and that’s the point. Like an airplane pilot landing in the dark, we want runway lights on either side of us, guiding us to the place where we can touch down our wheels.

we not only tend to compare things with one another but also tend to focus on comparing things that are easily comparable—and avoid comparing things that cannot be compared easily.

It has been shown repeatedly that the link between amount of salary and happiness is not as strong as one would expect it to be (in fact, it is rather weak). Studies even find that countries with the “happiest” people are not among those with the highest personal income. Yet we keep pushing toward a higher salary.

“Rich Now Envy the Superrich.”

In another news story, a physician explained that he had graduated from Harvard with the dream of someday receiving a Nobel Prize for cancer research. This was his goal. This was his dream. But a few years later, he realized that several of his colleagues were making more as medical investment advisers at Wall Street firms than he was making in medicine. He had previously been happy with his income, but hearing of his friends’ yachts and vacation homes, he suddenly felt very poor. So he took another route with his career—the route of Wall Street.3 By the time he arrived at his twentieth class reunion, he was making 10 times what most of his peers were making in medicine. You can almost see him, standing in the middle of the room at the reunion, drink in hand—a large circle of influence with smaller circles gathering around him. He had not won the Nobel Prize, but he had relinquished his dreams for a Wall Street salary, for a chance to stop feeling “poor.” Is it any wonder that family practice physicians, who make an average of $160,000 a year, are in short supply?*

We can also change our focus from narrow to broad. Let me explain with an example from a study conducted by two brilliant researchers, Amos Tversky and Daniel Kahneman. Suppose you have two errands to run today. The first is to buy a new pen, and the second is to buy a suit for work. At an office supply store, you find a nice pen for $25. You are set to buy it, when you remember that the same pen is on sale for $18 at another store 15 minutes away. What would you do? Do you decide to take the 15-minute trip to save the $7? Most people faced with this dilemma say that they would take the trip to save the $7. Now you are on your second task: you’re shopping for your suit. You find a luxurious gray pinstripe suit for $455 and decide to buy it, but then another customer whispers in your ear that the exact same suit is on sale for only $448 at another store, just 15 minutes away. Do you make this second 15-minute trip? In this case, most people say that they would not. But what is going on here? Is 15 minutes of your time worth $7, or isn’t it? In reality, of course, $7 is $7—no matter how you count it. The only question you should ask yourself in these cases is whether the trip across town, and the 15 extra minutes it would take, is worth the extra $7 you would save. Whether the amount from which this $7 will be saved is $10 or $10,000 should be irrelevant. This is the problem of relativity—we look at our decisions in a relative way and compare them locally to the available al...

For sure, James has made a lot of money, and he sees even more money all around him. One of his good friends, in fact, is a founder of PayPal and is worth tens of millions. But Hong knows how to make the circles of comparison in his life smaller, not larger. In his case, he started by selling his Porsche Boxster and buying a Toyota Prius in its place.4 “I don’t want to live the life of a Boxster,” he told the New York Times, “because when you get a Boxster you wish you had a 911, and you know what people who have 911s wish they had? They wish they had a Ferrari.” That’s a lesson we can all learn: the more we have, the more we want. And the only cure is to break the cycle of relativity.

Or, as Mark Twain once noted about Tom Sawyer, “Tom had discovered a great law of human action, namely, that in order to make a man covet a thing, it is only necessary to make the thing difficult to attain.”

The students enjoyed this class exercise, but when I asked them if they felt that writing down the last two digits of their social security numbers had influenced their final bids, they quickly dismissed my suggestion. No way! When I got back to my office, I analyzed the data. Did the digits from the social security numbers serve as anchors? Remarkably, they did: the students with the highest-ending social security digits (from 80 to 99) bid highest, while those with the lowest-ending numbers (1 to 20) bid lowest. The top 20 percent, for instance, bid an average of $56 for the cordless keyboard; the bottom 20 percent bid an average of $16. In the end, we could see that students with social security numbers ending in the upper 20 percent placed bids that were 216 to 346 percent higher than those of the students with social security numbers ending in the lowest 20 percent (see table on the facing page).

With everything you do, in fact, you should train yourself to question your repeated behaviors.

we generally believe we have precise and well-articulated preferences, but in reality, we only think that we know what we want.

The conclusion: no one is offended by a small gift, because even small gifts keep us in the social exchange world and away from market norms.

by the mention of its cost, the gift had passed into the realm of market norms.

Imagine that you work for me, and that I want to give you a year-end bonus. I offer you a choice: $1,000 in cash or an all-expenses-paid weekend in the Bahamas, which would cost me $1,000. Which option would you choose? If you are like most people who have answered this question, you would take the cash. After all, you may have already been to the Bahamas and may not have enjoyed being there very much, or maybe you’d prefer to spend a weekend at a resort closer to home and use the remainder of the bonus money to buy a new iPod. In either case, you think that you can best decide for yourself how to spend the money. This arrangement seems to be financially efficient, but would it increase your happiness with your work, or your loyalty to the company? Would it make me a better boss? Would it improve the employer-employee relationship in any way? I suspect that both your and my best interests would be better served if I simply didn’t offer you a choice and just sent you on the Bahamas vacation. Consider how much more relaxed and refreshed you would feel, and how well you would perform, after a relaxing weekend of sun and sand, compared with how you would feel and behave after you got the $1,000 bonus. Which would help you feel more committed to your job, more enjoyment in your work, more dedication to your boss? Which gift would make you more likely to stay long hours one night to meet an important deadline? On all of these, the vacation beats the cash hands down.

Gifts and employee benefits seem, at first glance, to be an odd and inefficient way of allocating resources. But with the understanding that they fulfill an important role in creating long-term relationships, reciprocity, and positive feelings, companies should try to keep benefits and gifts in the social realm.

The basic lesson, then, is that when we offer people a financial payment in a situation that is governed by social norms, the added payment could actually reduce their motivation to engage and help out.

when price is not a part of the exchange, we become less selfish maximizers and start caring more about the welfare of others.

Interestingly, these results suggest that although almost everyone has problems with procrastination, those who recognize and admit their weakness are in a better position to utilize available tools for precommitment and by doing so, help themselves overcome it.

Resisting temptation and instilling self-control are general human goals, and repeatedly failing to achieve them is a source of much of our misery.

What’s the bottom line? We have problems with self-control, related to immediate and delayed gratification—no doubt there. But each of the problems we face has potential self-control mechanisms, as well. If we can’t save from our paycheck, we can take advantage of our employer’s automatic deduction option; if we don’t have the will to exercise regularly alone, we can make an appointment to exercise in the company of our friends. These are the tools that we can commit to in advance, and they may help us be the kind of people we want to be.

By pairing something that we love with something that we dislike but that is good for us, we might be able to harness desire with outcome—and thus overcome some of the problems with self-control we face every day.

On the basis of Jack Knetsch, Dick Thaler, and Daniel Kahneman’s research on the “endowment effect,” we predicted that when we own something—whether it’s a car or a violin, a cat or a basketball ticket—we begin to value it more than other people do.

OUR PROPENSITY TO overvalue what we own is a basic human bias, and it reflects a more general tendency to fall in love with, and be overly optimistic about, anything that has to do with ourselves. Think about it—don’t you feel that you are a better-than-average driver, are more likely to be able to afford retirement, and are less likely to suffer from high cholesterol, get a divorce, or get a parking ticket if you overstay your meter by a few minutes? This positivity bias, as psychologists call it, has another name: “The Lake Wobegone Effect,” named after the fictional town in Garrison Keillor’s popular radio series A Prairie Home Companion. In Lake Wobegone, according to Keillor, “all the women are strong, all the men are good-looking, and all the children are above average.” I don’t think we can become more accurate and objective in the way we think about our children and houses, but maybe we can realize that we have such biases and listen more carefully to the advice and feedback we get from others.

IF I WERE to distill one main lesson from the research described in this book, it is that we are pawns in a game whose forces we largely fail to comprehend. We usually think of ourselves as sitting in the driver’s seat, with ultimate control over the decisions we make and the direction our life takes; but, alas, this perception has more to do with our desires—with how we want to view ourselves—than with reality.

A second main lesson is that although irrationality is commonplace, it does not necessarily mean that we are helpless. Once we understand when and where we may make erroneous decisions, we can try to be more vigilant, force ourselves to think differently about these decisions, or use technology to overcome our inherent shortcomings. This is also where businesses and policy makers could revise their thinking and consider how to design their policies and products so as to provide free lunches.