The Undoing Project: A Friendship that Changed the World(66)

At the end of the lunch, Amos invited Redelmeier to visit him in his office. It didn’t take long before Amos was bouncing ideas about the human mind off Redelmeier, as he had bounced them off Hal Sox, to listen for an echo in medicine. The Samuelson bet, for instance. The Samuelson bet was named for Paul Samuelson, the economist who had cooked it up. As Amos explained it, people offered a single bet in which they have a 50-50 chance either to win $150 or lose $100 usually decline it. But if you offer those same people the chance to make the same bet one hundred times over, most of them accept the bet. Why did they make the expected value calculation—and respond to the odds being in their favor—when they were allowed to make the bet a hundred times, but not when they are offered a single bet? The answer was not entirely obvious. Yes, the more times you play a game with the odds in your favor, the less likely you are to lose; but the more times you play, the greater the total sum of money you stood to lose. Anyway, after Amos finishing explaining the paradox, “He said, ‘Okay, Redelmeier, find me the medical analogy to that!’”

For Redelmeier, medical analogies popped quickly to mind. “Whatever the general example was, I knew a bunch of instantaneous medical examples. It was just astonishing that he would shut up and listen to me.” A medical analogy of Samuelson’s bet, Redelmeier decided, could be found in the duality in the role of the physician. “The physician is meant to be the perfect agent for the patient as well as the protector of society,” he said. “Physicians deal with patients one at a time, whereas health policy makers deal with aggregates.”

But there was a conflict between the two roles. The safest treatment for any one patient, for instance, might be a course of antibiotics; but the larger society suffers when antibiotics are overprescribed and the bacteria they were meant to treat evolved into versions of themselves that were more dangerous and difficult to treat. A doctor who did his job properly really could not just consider the interests of the individual patient; he needed to consider the aggregate of patients with that illness. The issue was even bigger than one of public health policy. Doctors saw the same illness over and again. Treating patients, they weren’t merely making a single bet; they were being asked to make that same bet over and over again. Did doctors behave differently when they were offered a single gamble and when they were offered the same gamble repeatedly?

The paper subsequently written by Amos with Redelmeier* showed that, in treating individual patients, the doctors behaved differently than they did when they designed ideal treatments for groups of patients with the same symptoms. They were likely to order additional tests to avoid raising troubling issues, and less likely to ask if patients wished to donate their organs if they died. In treating individual patients, doctors often did things they would disapprove of if they were creating a public policy to treat groups of patients with the exact same illness. Doctors all agreed that, if required by law, they should report the names of patients diagnosed with a seizure disorder, diabetes, or some other condition that might lead to loss of consciousness while driving a car. In practice, they didn’t do this—which could hardly be in the interest even of the individual patient in question. “This result is not just another manifestation of the conflict between the interests of the patient and the general interests of society,” Tversky and Redelmeier wrote, in a letter to the editor of the New England Journal of Medicine. “The discrepancy between the aggregate and the individual perspectives also exists in the mind of the physician. The discrepancy seems to call for a resolution; it is odd to endorse a treatment in every case and reject it in general, or vice versa.”

The point was not that the doctor was incorrectly or inadequately treating individual patients. The point was that he could not treat his patient one way, and groups of patients suffering from precisely the same problem in another way, and be doing his best in both cases. Both could not be right. And the point was obviously troubling—at least to the doctors who flooded the New England Journal of Medicine with letters written in response to the article. “Most physicians try to maintain this facade of being rational and scientific and logical and it’s a great lie,” said Redelmeier. “A partial lie. What leads us is hopes and dreams and emotion.”

Redelmeier’s first article with Amos led to other ideas. Soon they were meeting not in Amos’s office in the afternoon but at Amos’s home late at night. Working with Amos wasn’t work. “It was pure joy,” said Redelmeier. “Pure fun.” Redelmeier knew at some deep level that he was in the presence of a person who would change his life. Many sentences popped out of Amos’s mouth that Redelmeier knew he would forever remember:

A part of good science is to see what everyone else can see but think what no one else has ever said.

The difference between being very smart and very foolish is often very small.

So many problems occur when people fail to be obedient when they are supposed to be obedient, and fail to be creative when they are supposed to be creative.

The secret to doing good research is always to be a little underemployed. You waste years by not being able to waste hours.

It is sometimes easier to make the world a better place than to prove you have made the world a better place.

Redelmeier half suspected that the reason Amos had so much time for him was that Redelmeier was not married, and was willing to treat the hours between midnight and four in the morning as part of a workday. The hours Amos kept were strange, but the discipline he imposed became familiar. “He needs the concrete examples to test his general theories,” said Redelmeier. “Some of the principles were just extremely robust, and I was supposed to find examples and give voice to them in a particular domain, medicine.” Amos had a clear idea of how people misperceived randomness, for instance. They didn’t understand that random sequences seemed to have patterns in them: People had incredible ability to see meaning in these patterns where none existed. Watch any NBA game, Amos explained to Redelmeier, and you saw that the announcers, the fans, and maybe even the coaches seemed to believe that basketball shooters had the “hot hand.” Simply because some player had made his last few shots, he was thought to be more likely to make his next shot. Amos had collected data on NBA shooting streaks to see if the so-called hot hand was statistically significant—he already could persuade you that it was not. A better shooter was of course more likely to make his next shot than a less able shooter, but the streaks observed by fans and announcers and the players themselves were illusions. He asked Redelmeier to find in medicine the same sort of false pattern–seeking behavior exhibited by basketball announcers.