A Morte do Homem Racional

Um dos profetas da crise, Nouriel Roubini, que desde 2006 alertava sobre a possibilidade de um colapso no sistema financeiro, considera a relevância das finanças comportamentais na explicação dos problemas da economia mundial.

Em The Death of 'Rational Man' , David Ignatius, do The Washington Post (8/2/2009, B07) destaca o papel da leitura dos números, em especial do preço dos imóveis nos Estados Unidos, e as dicas de finanças comportamentais.

Quanto ao segundo ponto, a conclusão é simples: a teoria do homem racional não está funcionando, disse Roubini numa sessão do Fórum de Davos. E ele e outros economistas estão prestando mais atenção na questão comportamental, que inicia com as suposições sobre decisões econômicas.

Let me put in a plug here for the godfather of behavioral economics, John Maynard Keynes. His 1936 "General Theory" is often interpreted simplistically as a call for fixing recessions by boosting demand with government spending. But at a deeper level, Keynes was analyzing the role of psychological factors, such as greed and fear, in economic decisions. He understood that markets freeze when people panic and start hoarding cash. ("Extreme liquidity preference," he called it.) Conversely, economies start to roar when investors feel a surge of what Keynes called "animal spirits."

Discussão Thaler e Rizzo sobre Comportamento Humano

O Wall Street Journal promoveu uma discussão entre Thaler e Rizzo sobre o comportamento humano. A seguir a reprodução da discussão:

Should Policies Nudge People
To Make Certain Choices?

Driven by research in behavioral economics that suggests people don't always act in their own best interests, some economists are arguing for new policies that would challenge traditional "hard" tools for changing behavior, such as sin taxes and outright bans.

Such policies would often rely on default options that nudge, steer and coax -- but don't force -- individuals to make certain choices. Is this sensible governance? The Online Journal asked Mario Rizzo, a professor of economics at New York University and director of NYU's Program on the Foundations of the Market Economy, and Richard Thaler, professor of economics and behavioral science at the University of Chicago's Graduate School of Business, to hash it out.

What do you think? Share your comments on our discussion board.

* * *


Richard Thaler writes: Behavioral economics is founded on the unremarkable observation that human beings are imperfect decision makers. They have limited information-processing abilities, willpower, memory and attention. As a result, they make predictable errors by their own lights. Many Americans think of themselves as overweight; most 401(k) participants think they are saving too little; and nearly everyone thinks of himself as forgetful.

In light of human limitations, Cass Sunstein and I argue for policies that we call libertarian paternalism. Although the phrase sounds like an oxymoron, we contend that it is often possible to design policies, in both the public and private sector, that make people better off -- as judged by themselves -- without coercion. We oppose bans; instead, we favor nudges.

Consider two examples, both designed to increase savings. The first is to enroll people, automatically, into savings plans -- while allowing them to opt out. The second is the Save More Tomorrow plan, which allows employees to commit themselves now to increasing their savings rates later, when they get raises. Both approaches have been remarkably successful.

Well-chosen default rules are examples of helpful "choice architecture." Since it is often impossible for private and public institutions to avoid picking some option as the default, why not pick one that is helpful?

* * *


Mario Rizzo writes: The decisions of individuals may be imperfect but can the legal paternalist successfully steer them toward better decisions?

I say legal paternalist because Cass Sunstein and Richard Thaler clearly do not object to using coercion at the level of framing decisions. For example, they seem to approve of employers' being legally required to provide automatic 401(k) enrollment unless the employee opts out. But they also approve of mandatory cooling-off periods for consumer purchases; these cooling-off periods absolutely prevent individuals from concluding immediate exchanges even at lower prices.

It is a good thing to help people make better decisions. But law requires us to go beyond intention. What is the appropriate standard for better decisions? Thaler and Sunstein say it's what people would do if they had "complete information, unlimited cognitive abilities, and no lack of willpower." This is a very ambitious standard that could tax the abilities of even well-meaning policymakers.

Can we discover "true" preferences through individuals' statements that they are too fat and save too little? Talk is cheap. These could be expressions of mere desire, not a real willingness to make trade-offs between values. We all want to have more savings and more consumption, too.

Moreover, the public sector is not governed by science or even by behavioral economists, but by ambitious people with limited cognitive abilities, lack of willpower, and faulty memories, not to mention expanding waistlines. Whom should we trust more: individuals who face the costs and benefits of their own choices, or politicians and bureaucrats who do not?

Richard Thaler writes: It is both wrong and misleading to characterize libertarian paternalism as primarily an activity of governments. Automatic enrollment and Save More Tomorrow have been adopted in thousands of companies with no governmental involvement. When the government does get involved, we prefer nudges to requirements. A good example is the 2006 Pension Protection Act. Under that law, firms that offer to at least partially match their employees' contributions, enroll their employees automatically, and automatically escalate their contribution rates are given a waiver from some burdensome paperwork. No coercion is involved.

We agree that it can be difficult to determine people's true preferences. And it is an axiom of behavioral economics that intentions do not always -- or even usually -- lead to action. But statements of good intention can signal a desire for help in following through. Many employees have voluntarily signed up for the Save More Tomorrow program, and very few subsequently quit. We do not think that many people would sign up for "Smoke More Tomorrow," or "Eat More French Fries Tomorrow."

We agree that government workers are human. We are also happy to go on the record stipulating that politicians are boundedly rational. Some are also dishonest. Some are even fat. However, what are the implications of these obvious facts? Do we want to charge our political leaders with the task of making people worse off?

Often nudges are inevitable. Where they aren't, we agree that unless there is a good showing of need, government might do best to stand aside.

* * *


Mario Rizzo writes: Is New Paternalism primarily about advising private individuals and firms? If so, why use a political term -- libertarian -- to identify it?

It's true, some firms have adopted automatic 401(k) enrollment policies -- while fewer have adopted the Save More Tomorrow program. The market allows for this diversity while eliminating ineffective or inappropriate plans. No libertarian I know of has ever opposed privately adopted options. If this is all Thaler is saying, what's new?

But Thaler and Sunstein do go beyond this. Elsewhere, they've argued for costly contractual provisions like vacation time, allowing only termination for cause, non-waivable cooling-off periods, maximum 40-hour work weeks, and -- presumably -- the legal requirement of automatic savings plan enrollment, if not enough firms voluntarily adopt it. All this is said to be consistent with "libertarian paternalism."

Thaler says that those automatically enrolled in 401(k)s haven't quit, so they must be benefiting. This is an odd claim for a behavioral economist. Why would failure to change indicate a benefit? When the default is non-enrollment, Thaler says that individuals tend to stay in it because they're irrationally biased toward keeping the status quo.

The mistakes of bureaucrats, politicians and voters aren't as likely to be corrected by individual or social processes as errors made in the private sphere. Why? Because bureaucrats and politicians don't care about private welfare as much as individuals do and voters don't have much incentive to become informed. So people -- who make imperfect decisions -- tend to do less harm if they "nudge" only themselves and not others through policy choices.

* * *


Richard Thaler writes: I am glad Mario agrees with our private initiatives on retirement savings in which firms have nudged rather than required employees to take certain beneficial actions. Surveys of employers suggest that a majority will be offering automatic features by next year, a big step forward. Of course, the fact that few employees opt out is partly due to inertia, but most employees do get around to joining the plan under opt in, so the main gain from automatic enrollment is to get people to join sooner, something they appreciate.

Mario's major complaints are with positions that we do not advocate, namely what he calls the "legal imposition of costly contractual presumptions." We have never suggested that any particular contractual form be imposed, including automatic enrollment. See my previous post. Instead we stress that when governments do write laws, especially those mandating -- rather than nudging -- some action, they should do so with an eye toward making people better off. We do admit to liking some mandated -- and thus non-libertarian -- cooling-off periods under certain circumstances, as when buyers are especially likely to have made decisions under undue selling pressure. Who amongst us has not bought something under pressure that he would like to undo the next morning?

Mario's main misconception is that government can avoid nudging. It can't. The rules of the common law are legal rules that governments write. Whether governments are more or less corrupt than the private sector is an empirical question, and there are surely many examples of dumb or unethical behavior in both sectors. But this is beside the point. We favor better government, not more government. We urge both sectors to adopt libertarian paternalistic policies.

* * *


Mario Rizzo writes: I repeat: "Is New Paternalism primarily about advising private individuals and firms? If so, why use a political term -- libertarian -- to identify it?" It is simply a management-consulting philosophy.

If a firm chooses a default option, it is by no means inevitable that it must choose on the basis of paternalistic criteria. Under purely voluntary conditions, it will choose so as to enhance the attractiveness of its compensation package, that is, according to the actual preferences of its employees. Its goal is to maximize profits. To anticipate what employees or consumers want is the market principle, not paternalism. I repeat: "If this is all Thaler is saying, what's new?"

If automatic enrollment proves popular in the long run, then, at least most people must be aware of their procrastination bias -- assuming it exists -- and want to overcome it. The previously hostile legal environment had prevented employers from responding to this de-biasing preference.

As to the more intrusive examples of paternalism mentioned in my previous post, Richard and Cass Sunstein have indeed argued that they are consistent with libertarian paternalism. Let the reader decide.

The standard Richard advances that "when governments do write laws, especially those mandating -- rather than nudging -- some action, they should do so with an eye toward making people better off" may seem innocuous, but it is actually dangerous. This is because just about anything can slip by. (Satisfaction of informed preferences is an obscure criterion of "better off.") Such a standard could set in motion a slippery slope to much more intrusive interventions, especially in a world of boundedly rational individuals who tend to view the world in a narrow frame. It does not take corrupt public officials to go down this road. Self-interest and bounded rationality are quite enough.

* * *


Richard Thaler writes: Let's recapitulate. People make mistakes, so sometimes they can be helped. It is possible to help without coercion. That is libertarian paternalism. The concept can be and is used in both the public and private sectors. For example, in London, pedestrians from abroad are reminded by signs on the pavement to "look right" because their instincts from back home are to expect traffic to approach from the left. No one is forced to look right, but fewer pedestrians are hit by trucks.

Another example comes from Sweden, which launched a partial privatization of their social security system in 2000. The plan was open to any fund, which meant that participants faced 456 options. There was also a very well-designed default fund -- using private managers selected by the government -- that offered global diversification at very low fees (16 basis points). By any standard, both ex ante and ex post, the participants who selected their own portfolio of funds did worse than those who took the default plan. The main mistake the government made in designing this plan was to discourage participants from choosing the default fund, perhaps thinking, as Mario does, that choosing for oneself is always the best approach.

Mario thinks we are naïve about government. We think he is naïve about firms. Does he think that the companies that offered stock options to student loan officers to induce them to feature their loans had the "actual preferences" of the students at heart? Maximizing profits does not always mean maximizing the welfare of the customers.

Finally Mario seems to have a phobia about slippery slopes. I guess he thinks that if governments start with signs that say "look right," the next thing you know we will have Prohibition coming back. By the same logic, we should worry that if libertarians succeed in eliminating rent control that we will be soon down the slippery slope toward anarchy. Slippery slope arguments should be avoided unless there is proof that the slope is greased. In our case, by insisting, as we do, on only libertarian paternalism, the slope runs into a brick wall before it even gets started. And besides, what is the alternative? Inept neglect?

* * *


Mario Rizzo writes: Libertarianism is a political philosophy that seeks to reduce the activities of the state to a very low level. It is very much about less government. Paternalism is a political or moral philosophy that seeks to override the actual or operative preferences of individuals for their own benefit, however defined, according to Donald VanDeVeer's 1986 book on the subject. When applied to the actions of government, paternalism cannot be libertarian. It can only be more or less intrusive.

Does Richard wish to reduce his "libertarian paternalism" to the appropriate management of government-owned streets or other enterprises? In the London case, what people want is obvious: They don't want to get hit by cars. London is doing what entrepreneurs generally do: satisfying actual preferences. London is mimicking the market.

In Sweden, the government actively discouraged people from relying on the default investment option. People probably interpreted this as meaning the default option was not very good. They succumbed to this unfortunate inference because they viewed the government as an authoritative investment adviser. Government provision of investment advice is not consistent with libertarianism. But if it does provide advice, is it paternalistic to provide it in such a way that people make reasonable inferences? If Vanguard provides good advice, is that paternalism? In each case, this is just satisfying actual preferences for advice. (Note that none of this requires reference to the idea of "true" or "informed" preferences about which so big a deal was made.)

Richard wants to use the word "libertarian" to differentiate his paternalism from the traditional variants. Yet he uses the word in a fuzzy way. He wants to define libertarian along a continuous variable -- the cost of exercising the exit option. However, libertarianism, as every libertarian understands it, uses a bright-line test -- who imposes the cost? The authors of the concept of "libertarian paternalism" have said that clearly intrusive/coercive interventions are consistent with it. See my previous post. And they have also said, explicitly, that there is no sharp line between libertarian and non-libertarian paternalism. Thus, Richard cannot claim that his standard creates a bright-line rule that would help us resist the slippery slope.

Emoções e decisões morais

Um artigo de Fernando Reinach, que escreve semanalmente no Estadão, sobre finanças comportamentais.

Emoções e decisões morais Artigo
O Estado de São Paulo, p.a21

Fernando Reinach

A relação entre a moral e as emoções é parte subjacente da trama de grande parte dos romances, filmes e novelas.

Nossas decisões morais são influenciadas por nossas emoções ou seriam as emoções efeitos de nossos conflitos morais? Até recentemente esse tipo de problema pertencia ao campo da filosofia e da psicologia, mas agora neurocientistas estão abordando essas questões experimentalmente.

Imagine que você se defronte com o seguinte problema: um pequeno vagão vem descendo sem controle por um trilho que desemboca em uma bifurcação. Cabe a você operar um comando que determina se o vagão vai para a direita ou para a esquerda. Se você desviá-lo para a esquerda ele vai atropelar e matar cinco pessoas. Se você desviá-lo para a direita ele vai matar uma única pessoa.

Diante desse dilema moral, a grande maioria das pessoas escolhe a solução do mal menor: desvia o vagão para a direita sacrificando um para salvar cinco. Imagine agora que o vagão vem descendo a ladeira em direção às cinco pessoas, mas, antes, vai passar por baixo de uma ponte. Você está em cima da ponte e tem de tomar uma decisão. Ou não faz nada e deixa as cinco pessoas morrerem ou agarra uma pessoa que está em cima da ponte e a lança sobre os trilhos para parar o vagão.

Apesar de o número de pessoas mortas ser idêntico em cada opção (cinco mortes ao invés de uma), a grande maioria das pessoas prefere deixar as cinco pessoas morrerem a tomar a atitude de fisicamente jogar uma pessoa inocente nos trilhos e causar sua morte.

Recentemente, esse e outros experimentos do mesmo tipo foram repetidos com pacientes com uma lesão no córtex pré-frontal. Seis pacientes foram escolhidos pelo fato de terem lesões causadas por tumores ou por derrames em uma região específica do cérebro que, se destruída, reduz a capacidade da pessoa de sentir emoções como empatia, culpa ou vergonha.

Apesar de não sentirem essas emoções, os pacientes tinham capacidade de raciocínio e inteligência normais. O que foi observado é que os pacientes com a lesão tomavam as mesmas decisões que as pessoas normais quando as escolhas morais não envolviam aspectos sentimentais muito próximos ao indivíduo. Assim, nos exemplos acima, esses pacientes reagiram da mesma maneira que pessoas normais no caso do desvio do vagão.

Ao contrário das pessoas normais, mesmo quando a decisão envolvia pessoas próximas, os pacientes com a lesão tendiam a escolher a opção lógica. No exemplo da ponte, não hesitavam em atirar uma pessoa da ponte para salvar outras cinco. A conclusão desse estudo é que nossas decisões morais são intrinsecamente dependentes de fatores emocionais, mas que essa influencia só altera o julgamento quando a decisão moral envolve pessoas ou situações muito próximas ao sujeito.

Esse resultado não é inesperado, afinal a própria Justiça reconhece que o julgamento moral das pessoas pode ser bloqueado quando a decisão envolve pessoas ou situações muito próximas a cada um de nós. O interessante é que, pela primeira vez, se obtém comprovação experimental para essa observação, inclusive com o mapeamento das regiões do cérebro envolvidas nos fenômenos. Aos poucos a biologia vai explicando fenômenos mentais que antes pareciam exclusividade da filosofia.

Mais informações em Damages to the prefrontal córtex increases utilitarian moral judgements, na Nature, volume 446, página 908, 2007.

Sorte no mercado chinês

Uma reportagem do Wall Street Journal, 28/05/2007, mostra como a questão da superstição afeta o investimento no mercado acionário chinês:

Nas bolsas chinesas, a chave está no '8'
James T. Areddy, The Wall Street Journal
The Wall Street Journal Americas

XANGAI — Quando um amigo lhe deu várias dicas de investimentos acionários no ano passado, Yan Caigen comprou 30.000 ações de uma delas, uma fabricante de cimento. O motivo: o código da empresa, 600881, continha dois auspiciosos oitos.

"Eu acredito que bons códigos dão boa sorte", diz Yan, que passa quase todos os seus dias diante do monitor na corretora Shenyin & Wanguo Securities Co., de Xangai. De fato, a ação da Jilin Yatai Group Co., a fabricante de cimento em que ele apostou, rapidamente triplicou, gerando um lucro de US$ 50.000. Yan atribui o desempenho aos dois "8" no código numérico da ação, que ele considera uma combinação que dá sorte.

Parte superstição, parte profecia auto-realizável, a numerologia é uma estratégia básica da negociação de ações na China. Ela mostra como é amplamente disseminada na sociedade chinesa a crença de que os números contêm pistas para a boa sorte.

É uma crença pouco notada e que vem alimentando a alta das bolsas da quarta maior economia do mundo, cuja influência sobre outros mercados acionários tem crescido, como ficou evidente em fevereiro, quando uma forte queda em Xangai derrubou bolsas ao redor do planeta, de Frankfurt a São Paulo. O Índice Composto de Xangai subiu mais de 56% neste ano e já quadruplicou seu nível de meados de 2005, uma alta que vem gerando temores de uma bolha no mercado.

O fervor dos investidores com a numerologia também ajuda a explicar por que o governo chinês não tem conseguido esfriar o entusiasmo nas bolsas através de medidas convencionais, como a restrição ao crédito na semana passada.

Para observadores do mercado, a confiança dos investidores chineses no poder profético dos números — em vez de fundamentos econômicos, como perspectivas de negócios ou lucro — é um dos muito sinais de que o investimento nas bolsas de Xangai ou de Shenzhen parece uma jogatina.

As corretoras são organizadas como se fossem cassinos. Os investidores tomam chá, fumam e conversam enquanto negociam em máquinas parecidas com caça-níqueis. Em vez de colocar moedas, eles passam o cartão para pagar pelas ações.

"Somos investidores individuais. Geralmente escolhemos às cegas qual ação vamos comprar", diz Chen Guoan, investidor de Xangai. Alguns distribuem cigarros para congratular os amigos quando a ação sobe.

Pessoas comuns, que geralmente entendem pouco ou nada de finanças, representam de 60% a 80% dos investidores na China. Nos Estados Unidos, por exemplo, o mercado é dominado por gigantes financeiros como Goldman Sachs Group Inc., Merrill Lynch & Co. e Fidelity Investments Inc. "Vêem-se coisas estranhas com as ações, com números e códigos da sorte", diz Jing Ulrich, presidente de investimentos na China do J.P. Morgan Chase & Co. "Isso reflete um mercado muito imaturo."

A maioria da classe média urbana da China não tem dinheiro nos quase 100 milhões de contas de corretagem do país. Novos investidores em número recorde, geralmente com pouco conhecimento sobre a mecânica do mercado, também estão entrando de cabeça nas bolsas, abrindo em média mais de 100.000 novas contas por dia neste ano. O governo já alertou para o perigoso nível de especulação, já que os investidores estão financiando suas compras de ações com empréstimos ou cartões de crédito. Nas últimas semanas, o valor diário do volume de transações chegou a quase US$ 50 bilhões.

A falta de uma imprensa livre na China e as restrições que as autoridades impõem ao que os analistas podem dizer publicamente deixam os investidores vulneráveis a teorias de negociação inusitadas. Eles em geral se valem de conselhos como o de usar roupas vermelhas, que representam um mercado "aquecido", e a evitar referências ao "pai", já que a palavra em chinês é homônima para "queda".

— Tang Hanting e Ellen Zhu colaboraram neste artigo.

Regras e Comportamento

As pessoas reagem as regras. Esta é uma verdade que tem sido comprovada diariamente. Um estudo interessante mostra uma aplicação disto nas corridas da Nascar. Este tipo de corrida inspirou a Stock Cars brasileira.

Desde 2003 a Nascar criou duas etapas. Numa primeira etapa, os corredores da Nascar tentam classificar para a etapa final, onde somente os dez primeiros colocados participam. A etapa final possui dez corridas. Isto mudou os incentivos dos corredores.

Se um corredor está fora dos dez primeiros, ele irá arriscar mais sua corrida para tentar obter uma boa classificação. Isto, naturalmente, pode resultar em acidentes ou em carros que não terminam a corrida.

O estudo citado acima mostra que a probabilidade de um acidente aumentou com a mudança de regras. Usando uma regressão linear, com variável binária (ou dummy), o autor do blog encontrou resultados expressivos.

Linha do tempo em Finanças Comportamentais

A linha do tempo de Finanças Comportamentais, usando o Google Timeline, é interessante. O ápice ocorre no final da década de 1990 (1999). Será que o interesse em Finanças Comportamentais diminuiu?

Clique aqui e veja

Entrevista com Thaler

Uma interessante entrevista com Richard Thaler, para o New Yorke Times Magazine (11/02/2001) (via Game Theory Readings) realizada por Roger Lowenstein. Lowenstein escreve livros de finanças (um deles sobre Buffett). Destaquei, no texto abaixo, os trechos que achei interessante (em negrito) como o desprezo dos economistas clássicos e o estudo da garrafa de vinho.

Exuberance Is Rational
New York Times Magazine
11 February 2001
New York Times Magazine


Or at least human. Richard Thaler has led a revolution in the study of economics by understanding the strange ways people behave with their money.
by Roger Lowenstein



It is possible that Richard Thaler changed his mind about economic theory and went on to challenge what had become a hopelessly dry and out-of-touch discipline because, one day, when a few of his supposedly rational colleagues were over at his house, he noticed that they were unable to stop themselves from gorging on some cashew nuts he'd put out. Then again, it could have been because a friend admitted to Thaler that, although he mowed his own lawn to save $10, he would never agree to cut the lawn next door in return for the same $10 or even more. But the moment that sticks in Thaler's mind occurred back in the 1970's, when he and another friend, a computer maven named Jeff Lasky, decided to skip a basketball game in Rochester because of a swirling snowstorm.

"But if we had bought the tickets already, we'd go," Lasky noted.

"True -- and interesting," Thaler replied.

Thaler began to make note of these episodes -- anomalies, he called them -- and to chalk them up on his blackboard at the University of Rochester, where he was a young, unheralded and untenured assistant professor. Each of these stories was at odds with neoclassical economics as it was taught in graduate schools; indeed, each was a tiny subversion of the prevailing orthodoxy. According to accepted economic theory, for instance, a person is always better off with more rather than fewer choices. So why had Thaler's colleagues roundly thanked him for removing the tempting cashews from his living room? The lawn example was even more troubling. Perhaps you dimly remember from Economics 101 that unlovely term, "opportunity cost." The idea, as your pointy-headed prof vainly tried to persuade you, is that forgoing a gain of $10 to mow a neighbor's lawn "costs" just as much as paying somebody else to mow your own. According to theory, you either prefer the extra time or the extra money -- it can't be both. And the basketball tickets refer to "sunk costs." No sense going to the health club just because we have paid our dues, right? After all, the money is already paid -- sunk. And yet, Thaler observed, we do. People, in short, do not behave like the pointy heads say they should.

In the ordered world of economics, this rated as a heresy on the scale of Galileo. According to the standard or neoclassical school (essentially a 20th-century updating of Adam Smith), people, in their economic lives, are everywhere and always rational decision makers; those who aren't either learn quickly or are punished by markets and go broke. Among the implications of this view are that market prices are always right and that people choose the right stocks, the right career, the right level of savings -- indeed, that they coolly adjust their rates of spending with each fluctuation in their portfolios, as though every consumer were a mathematician, too. Since the 1970's, this orthodoxy has totally dominated the top universities, not to mention the Nobel Prize committee.

Thaler spearheaded a simple but devastating dissent. Rejecting the narrow, mechanical homo economicus that serves as a basis for neoclassical theory, Thaler proposed that most people actually behave like . . . people! They are prone to error, irrationality and emotion, and they act in ways not always consistent with maximizing their own financial well being. So serious was Thaler's challenge that Merton Miller, the late Nobelist and neoclassical deity, refused to talk to him; Thaler's own thesis adviser lamented that he had wasted a promising career on trivialities like cashews. Most economists simply ignored him.

But the anomalous behaviors documented by Thaler and a band of fellow dissenters, including Yale's Robert Shiller and Harvard's Lawrence Summers, Clinton's last treasury secretary, have grown too numerous to ignore. And the renegades, though still a minority, have embarked on a second stage: an attempt to show that anomalies fall into recognizable and predictable patterns. The hope is that by illuminating these patterns, behavioral economics, as it has come to be called, will yield a new understanding of the economy and markets. Behaviorism, says Daniel McFadden, the recent Nobel laureate, "is a fundamental re-examination of the field. It's where gravity is pulling economic science."

Thaler, after years of being shunned, is now a popular, highly paid professor at the University of Chicago Graduate School of Business, the traditional nerve center of neoclassicism. His increasing following is owed in no small part to the fact that behaviorism, unlike so much of economics, is fun. Although prewar economists like John Maynard Keynes were literary artists, most writing in the field since the 70's has been obtuse and highly mathematical, all but inaccessible to the lay person. By contrast, Thaler's papers are rich with intuitive gems drawn from sports, business and everyday life. In one paper, he pointed out that people go across town to save $10 on a clock radio but not to save $10 on a large-screen TV. It's a seemingly obvious point -- and also a direct contradiction of rationalist theory.

Thaler loves pointing out that not even economics professors are as rational as the guys in their models. For instance, a bottle of wine that sells for $50 might seem far too expensive to buy for a casual dinner at home. But if you already owned that bottle of wine, having purchased it earlier for far less, you'd be more likely to uncork it for the same meal. To an economist (a sober one, anyway) this makes no sense. But Thaler culled the anecdote from Richard Rosett, a prominent neoclassicist.

A thickset man of 55, Thaler has a sharp wit and a voluble ego. Many assume that his years in the academic wilderness have made him defensive; Thaler denies it. "The last thing I want to do is to sound embittered about having to struggle," he told me, easing his Audi around Lake Michigan toward the Gothic stone campus. But Thaler doesn't so much debate opponents; he skewers them. The British economist Ken Binmore once proclaimed at a seminar that people evolve toward rationality by learning from mistakes. Thaler retorted that people may learn how to shop for groceries sensibly because they do it every week, but the big decisions -- marriage, career, retirement -- don't come up that often. So Binmore's highbrow theories, he concluded, were good for "buying milk."

I met Thaler two days after the election, and he was already predicting that the country would be willing to accept Bush as the winner, because "people have a bias toward the status quo." I asked how "status-quo bias" affects economics, and Thaler observed that workers save more when they are automatically enrolled in savings programs than when they have to choose to participate by, say, returning a form. Standard theory holds that workers would make the most rational decision regardless.

Savings is an area where Thaler thinks he can have a big impact. Along with Shlomo Benartzi, a collaborator at U.C.L.A., Thaler cooked up a plan called Save More Tomorrow. The idea is to persuade employees to commit a big share of future salary increases to their retirement accounts. People find it less painful to make future concessions because pain deferred is, to an extent, pain denied. Therein lies the logic for New Year's resolutions. Save More Tomorrow was tried with a Chicago company, and workers tripled their savings within a year and a half -- an astounding result. "This is big stuff," Thaler says. He is shopping the plan around to other employers and predicts that eventually it could help raise the country's low savings rate.

Though Thaler, who comes across as a middling, Robert Rubin-style Democrat, plays down the connection, such results could provide ammunition to liberals who think government bashing has gone too far. Since the Reagan era, a mantra for office seekers is that people know what is best for themselves. Generally, yes; but what if not always, and what if they err in predictable ways? For instance, Thaler has found that the number of options on a 401(k) menu can affect the employees' selections. Those with a choice of a stock fund and bond fund tend to invest half in each. Those with a choice of three stock funds and one bond fund are likely to sprinkle an equal amount of their savings in each, and thus put 75 percent of the total in stocks. Such behavior illustrates "framing" -- decisions being affected by how choices are positioned. Political pollsters and advertisers have known this for years, though economists are just coming around.

Framing has big implications for the debate on privatizing Social Security. Neoclassicists say that people should manage their own retirement accounts, and that the more choices they have the better. Thalerites are not so sure. "If Thaler is right, it makes the current dogmatic antipaternalism really doubtful," says Cass Sunstein, a prominent legal scholar at the University of Chicago.

Thaler, who grew up in Chatham, N.J., the son of an actuary, wrote his doctoral thesis at the University of Rochester on the economic "worth" of a human life (public planners tackle this morbid theme frequently, for instance, in determining speed limits). Thaler conceived a clever method of calculation: measuring the difference in pay between life-threatening jobs like logging and safer lines of work. He came up with a figure of $200 a year (in 1967 dollars) for each 1-in-1,000 chance of dying.

Sherwin Rosen, his thesis adviser, loved it. Thaler did not. He had been asking friends about it, and most insisted that they would not accept a 1-in-1,000 mortality risk for anything less than a million dollars. Paradoxically, the same friends said they would not be willing to forgo any income to eliminate the risks that their jobs already entailed. Thaler decided that rather than rationally pricing mortality, people had a cognitive disconnect; they put a premium on new risks and casually discounted familiar ones.

For a while, Thaler regarded such anomalies as mere cocktail-party fodder. But in 1976 he happened upon the work of two psychologists, Daniel Kahneman and the now-deceased Amos Tversky, who had been studying many of the same behaviors as Thaler. The two had noticed a key pattern: people are more concerned with changes in wealth than with their absolute level -- a violation of standard theory that explained many of Thaler's anomalies. Moreover, most people are "loss averse," meaning they experience more pain from losses than pleasure from gains. This explains why investors hate to sell losers. For Thaler, their work was an epiphany. He wrote to Tversky, who plainly encouraged him. "He took me seriously," Thaler recalled, "and because of that, I started taking it seriously."

Thaler began designing experiments to test his ideas. In one, Thaler told lab subjects to imagine they are stranded on a beach on a sweltering day and that someone offers to go for their favorite brand of beer. How much would they be willing to pay? Invariably, Thaler found, subjects agree to pay more if they are told that the beer is being purchased from an exclusive hotel rather than from a rundown grocery. It strikes them as unfair to pay the same. This violates the bedrock principle that one Budweiser is worth the same as another, and it suggests that people care as much about being treated fairly as they do about the actual value of what they're paying for. Although "fairness" is generally ignored by neoclassicists, it's probably a reason why companies do not lower salaries when they encounter tough times -- perversely, laying off workers is considered more fair.

Thaler's first paper on anomalies was rejected by the leading economic journals. But in 1980, a new publication, The Journal of Economic Behavior and Organization, was desperate for copy, and Thaler's "Toward a Positive Theory of Consumer Choice" saw the light of day. "I didn't have any data," he admits. "It was stuff that was just true."

The response from fellow economists was zero. But the article eventually caught the eye of Eric Wanner, a psychologist at the Alfred P. Sloan Foundation in New York. Wanner was itching to get economists and psychologists talking to one another, and Thaler took the bait. "He was the first economist who thought hard about the implications for economics," Wanner says. "The reaction of mainstream economists was defensive and hostile. They considered it an attack -- an apostasy." Wanner, who became president of the Russell Sage Foundation, started financing behavioral economics, and Thaler became the informal leader, organizing seminars and summer workshops. In effect, he turned an idea into a movement.

"Dick was like a taxonomist who goes out and collects embarrassing specimens," Wanner says. "He learned that to get anyone to pay attention to him he had to develop a portfolio of facts that he could be entertaining about and that economists couldn't sweep under the rug."

Thaler's most original contribution was "mental accounting" -- an extension of Kahneman and Tversky's "framing" principle. "Framing" says the positioning of choices prejudices the outcome. "Mental accounting" says people draw their own frames, and that where they place the boundaries subtly affects their decisions. For instance, a poker player who accounts for each day separately may become bolder at the end of a winning night because he feels he is playing with "house money." If he accounted for each hand separately, he would play the first and last hands the same.

Most people sort their money into accounts like "current income" and "savings" and justify different expenditures from each. They'll gladly blow their winnings from the office football pool, a "frivolous" account, even while scrupulously salting away every penny of their salaries.

Thaler and a trio of colleagues went on to document that cabdrivers stop working for the day when they reach a target level of income. (Each day's "account" is separate.) This means that -- quite nonsensically -- they work shorter hours on more lucrative days, like when it's raining, and longer hours on days when fares are scarce! In a sense, investors who pay attention to short-term fluctuations are like those cabbies; if they toted up their stocks less frequently, they would be better investors. Thaler went so far as to suggest to an audience at Stanford that investors should be barred from seeing their portfolios more than once every five years.

Such irreverence reinforced the view among economists that Thaler could be safely ignored. His anecdotes were fuzzy science, they said, and examples like the cabbies were easy pickings. Since there is no way for a third party to profit from a cabbie's mistake, it's not surprising that he would make one. Thaler knew the criticism had merit, and that to be taken seriously, he had to demonstrate irrationalities in financial markets, which are the purest embodiment of neoclassicism. In the markets, one person's bad decision can be offset by someone else's smart one. Across the markets, rationality should reign.

Thaler set out to prove that it did not. His first effort, a 1985 paper with Werner De Bondt, his doctoral student, showed that stocks tend to revert to the mean -- that is, stocks that have outperformed for a sustained period are likely to lag in the future and vice versa. This was a finding that Chicago School types couldn't ignore -- according to their theory, no pattern can be sustained, since if it did, canny traders would try to profit from it, correcting prices until the pattern disappeared.

Then, in 1987, Thaler was hired to write a regular Anomalies column for a new economics journal, giving him a widespread audience among his peers. That same year, the stock market crashed 23 percent on a single day. Thaler could hardly have imagined better proof that the market was not, well, perfectly rational. More economists began to mine the data, and by the 90's there was a rich literature of market anomalies, documenting, for example, that people can consistently make money on stocks that trade at low multiples of earnings, or on companies that signal changes by doing things like hiking dividends. Documenting anomalies became a popular pastime from Berkeley to Harvard.

Thaler still has plenty of critics. The harshest one is right upstairs from his office at Chicago, the curmudgeonly Eugene Fama, a longtime advocate of the efficient-market school. "What Thaler does is basically a curiosity item," Fama snipes. "Would you be surprised that every shopper doesn't shop at the lowest prices? Not really. Does that mean that prices aren't competitive?"

Thaler periodically invites Fama in to his class to present the other side, but Fama has not returned the gesture and, indeed, sounds bitter that behavioral finance is getting so much attention. "One question that occurs to me," Fama says, "is, 'How did some of this stuff ever get published?"' The objection raised most often, from Fama and others, is that if Thaler is right and the market is so screwy, why wouldn't more fund managers be able to beat it? A variation of this theme is that if behavioral economics, for all its intuitive appeal, can't help people make money, what good is it?

Thaler, actually, is a director in a California money management firm, Fuller & Thaler Asset Management, which, according to figures it provided, has been beating the market handily since 1992. The firm tries to exploit various behavioral patterns, like "categorization": when Lucent Technologies was riding high, people categorized it as a "good stock" and mentally coded news about it in a favorable way. Lately, Lucent has become a "bad stock." But Thaler, who does not get involved in picking stocks, stops short of suggesting that investors versed in his research can beat the market. Mispricings that spring from anomalies are hard to spot, he says, particularly when the people looking for them are prone to their own behavioral quirks.

If this sounds muted, it may be because Thaler is ready to declare victory and join the establishment. The neoclassical model, he admits, is a fine starting point; it's misleading only when regarded as a perfect or all-encompassing description. People aren't crazy, he adds, but their rationality is "bounded" by the tendencies that Kahneman, Tversky, himself and others have studied. What he hopes is that a future generation will resolve the schism by building behavioral tendencies into a new, more flexible model.

For now, Thaler is still looking for new miniature applications wherever he can find them, like on the basketball court recently. Thaler studied games in which a team trails by 2 points, with time left for just one shot. What to go for, 2 points or 3? A 2-point shot succeeds about half the time, a 3-pointer about 33 percent of the time. But since a 2-point basket would only tie the game (and force an overtime, in which the team has a 50-50 chance of winning), going for a 3-pointer is a superior strategy. Still, most coaches go for 2. Why? Because it lowers the risk of sudden loss. Coaches, like the rest of us, do more to avoid losing than they do to win. You won't find an explanation for that in the mechanical homo economicus of theory. But it has everything to do with folks Thaler thinks are much more relevant to the economy -- Homo sapiens.

Copyright 2001 The New York Times Company

Behavioral economics x Behavioral Finance

No artigo Behavioral Law and Economics, de Christine Jolls (clique aqui, em PDF) uma citação interessante:

"O último sinal de sucesso da behavioral economics será quando se tornar simplesmente economics"

É interessante notar que o termo Behavioral economics tem sido constantemente utilizado na literatura técnica. O termo behavioral accounting parece que não "pegou".