lunedì 27 marzo 2017

Quando la stupidità è a buon mercato

Gli economisti sono spesso rimproverati per assumere la razionalità dei comportamenti umani a base del loro modello. Effettivamente l'ipotesi è "forte" ma il suo abbandono non è semplice, richiede metodo.
Una delle proposte di "allentamento" più promettenti è quella formulata da Bryan Caplan in "The Myth of the Rational Voter: Why Democracies Choose Bad Policies".
La domanda da cui si parte è: perché le democrazie spesso partoriscono politiche sconcertanti? Le dittature potrebbero impegnarsi in cattive politiche ma non in politiche sconcertanti.
Ed ecco la risposta: perché gli elettori sono irrazionali.
Ma perché gli elettori dovrebbero essere irrazionali?
L'ipotesi dell'irrazionalità umana generalizzata è qualcosa di assurdo, il mondo andrebbe a catafascio domani. Del resto una persona non può essere razionale il Lunedì e irrazionale il Martedì...
... If people are rational on Monday and irrational on Tuesday, it is a good idea to shift decision-making to Monday...
Ancora: chi sostiene l'irrazionalità dell' elettore non può fare un'ipotesi ad hoc...
... One could postulate voter irrationality as an ad hoc exception to the laws of human behavior. But ad hoc exceptions to well-established principles understandably provoke skepticism...
Bisogna dunque avere una teoria dell’irrazionalità per essere credibili quando si dice, per esempio, che l’elettore è irrazionale.
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Partiamo da una considerazione all'apparenza pacifica: a noi piace credere alcune cose più di altre. In altri termini, la verità non è l'unico criterio guida della ricerca, ci sono anche i gusti personali. Alcune idee piacciono più di altre. Le preferenze non riguardano solo i colori delle cravatte o la foggia del vestito ma anche le idee. Questo è talmente vero che riusciamo a credere anche l'impossibile. Lo spiega bene la Regina in “Alice nel paese delle meraviglie”...
... Alice laughed. “There’s no use trying,” she said. “One ca’n’t believe impossible things.” “I dare say you haven’t had much practice,” said the Queen. “When I was your age, I always did it for half- an-hour a day. Why, sometimes I’ve believed as many as six impossible things before breakfast.”...
Cosa ostacola la ricerca della verità? Innanzitutto l'interesse...
... The desire for truth can clash with other motives. Material self-interest is the leading suspect. We distrust salesmen because they make more money if they shade the truth...
La ricerca indipendente, per esempio, è più credibile...
... Dasgupta and Stiglitz deride the free-market critique of antitrust policy as “well-funded” but “not well-founded.”...
Poi c'è un altro fattore: la pressione sociale...
... Social pressure for conformity is another force that conflicts with truth-seeking.6 Espousing unpopular views often transforms you into an unpopular person...
Ma avidità e conformismo non esauriscono l'elenco, c'è anche la passione a corrompere la ricerca...
... On many topics, one position is more comforting, flattering, or exciting, raising the danger that our judgment will be corrupted not by money or social approval, but by our own passions. Even on a desert isle, some beliefs make us feel better about ourselves. Gustave Le Bon refers to “that portion of hope and illusion without which [mean] cannot live.”...
La credenza religiosa è spesso minata dalla passione per essere attendibile. Gaetano Mosca sul piacere fisico di avere ragione...
... The Christian must be enabled to think with complacency that everybody not of the Christian faith will be damned. The Brahman must be given grounds for rejoicing that he alone is descended from the head of Brahma and has the exalted honor of reading the sacred books. The Buddhist must be taught highly to prize the privilege he has of attaining Nirvana soonest. The Mohammedan must recall with satisfaction that he alone is a true believer, and that all others are infidel dogs in this life and tormented dogs in the next. The radical socialist must be convinced that all who do not think as he does are either selfish, money-spoiled bourgeois or ignorant and servile simpletons. These are all examples of arguments that provide for one’s need of esteeming one’s self and one’s own religion or convictions and at the same time for the need of despising and hating others....Le credenze sono una coperta di Linus. Le illusioni durano perchè ci servono. Chi ha una fede religiosa vive mediamente meglio. Le dimostrazioni non servono.
La psicologia conferma il fenomeno...
... Jost and his coauthors casually remark in the Psychological Bulletin that “Nearly everyone is aware of the possibility that people are capable of believing what they want to believe, at least within certain limits.”...
Ma come facciamo a sapere con sicurezza che le cose stiano in questi termini? D'altronde, gli economisti dicono che le preferenze sono inosservabili se non si traducono in comportamenti. Ma questa verità è dubbia. Innanzitutto posso farmi un bell'esame di coscienza e verificare le mie di preferenze...
... I observe one person’s preferences every day—mine. Within its sphere I trust my introspection more than I could ever trust the work of another economist... One thing my introspection tells me is that some beliefs are more emotionally appealing than their opposites...
E gli altri?...
... Introspection is a fine way to learn about your own preferences. But what about the preferences of others?... The simplest way to check is to listen...
George Berkeley sul potere del pensiero...
... I can easily overlook any present momentary sorrow when I reflect that it is in my power to be happy a thousand years hence. If it were not for this thought I had rather be an oyster than a man...
Samuelson sulla gioia della scoperta...
... Paul Samuelson himself revels in the Keynesian revelation... the joy of the General Theory...
D'altro canto, cambiare idea è spesso un tormento. Testimonianze sulla de-comunistizzazione del proprio spirito...
... Many autobiographies describe the pain of abandoning the ideas that once gave meaning to the author’s life. As Whittaker Chambers puts it: So great an effort, quite apart from its physical and practical hazards, cannot occur without a profound upheaval of the spirit… No wonder that—in his own words—Chambers broke with Communism “slowly, reluctantly, in agony.”21 For Arthur Koestler, deconversion ... was “emotional harakiri.”. ..
Speranza e illusione sono tipici anche della malattia mentale...
... The desire for “hope and illusion” plays a role even in mental illness.23 According to his biographer, Nobel Prize winner and paranoid schizophrenic John Nash often preferred his fantasy world—where he was a “Messianic godlike figure”...
Sulla bellezza della teoria dello sfruttamento di Marx...
... Listen to Böhm-Bawerk trace the psychological appeal of Marxian exploitation theory: It drew up the line of battle on a field where the heart, as well as the head is wont to speak. What people wish to believe, they believe very readily. . . . When the implications of a theory point toward raising the claims of the poor and lowering those of the rich, many a man who finds himself faced with that theory will be biased from the outset. And so he will in large measure neglect to apply that critical acuity which he ordinarily would devote to an examination of scientific justification...
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Ma gli errori hanno un costo. Se di mezzo c'è l'incolumità di tuo figlio sei meno propenso a considerare la bellezza delle teorie...
... It is dangerous to think that poisonous substances are candy. It is dangerous to reject the theory of gravity at the top of the stairs...
Alcune credenze non sono però così costose, penso all’interpretazione della storia… 
... The cost of error varies with the belief and the believer’s situation. For some people, the belief that the American Civil War came before the American Revolution would be a costly mistake. A history student might fail his exam... Normally, however, a firewall stands between this mistake and “real life.” Historical errors are rarely an obstacle to wealth, happiness, descendants, or any standard metric of success. The same goes for philosophy, religion, astronomy, geology, and other “impractical” subjects... Virtually the only way that mistakes on these questions injure you is via their social consequences. A lone man on a desert island could maintain practically any historical view with perfect safety...
Diciamo meglio: alcune credenze hanno un elevato costo privato, altre un basso costo privato (anche se magari possono avere un alto costo pubblico).
Quando i costi privati di una credenza sono bassi le persone vanno a ruota libera. Joseph Schumpeter...
... the typical citizen drops down to a lower level of mental performance as soon as he enters the political field...
Possiamo partire da qui per delineare una "logica dell'irrazionalità". Ecco un possibile modello dell'irrazionalità politica...
... People have preferences over beliefs: A nationalist enjoys the belief that foreign-made products are overpriced junk; a surgeon takes pride in the belief that he operates well while drunk. Figure 5.2 The Demand for Irrationality • False beliefs range in material cost from free to enormous: Acting on his beliefs would lead the nationalist to overpay for inferior domestic goods, and the surgeon to destroy his career. Snapping these two building blocks together leads to a simple model of irrational conviction...
Si tratta di una prospettiva ben diversa rispetto al consueto modello dell'ignoranza razionale...
... rational ignorance assumes that people tire of the search for truth, while rational irrationality says that people actively avoid the truth...
Ci sarebbe dunque una domanda di irrazionalità. Credere è bello (anche quando è stupido).
Finché il prezzo è accessibile si compra. Nel modello dell'ignoranza razionale l'elettore non ha convenienza ad informarsi. Nel modello "rational irrational" l'elettore ha convenienza a professare le idee che lo rendono più felice (anziché quelle vere).
La teoria ha una sua plausibilità psicologica?
Spesso in noi convivono più pensieri...
... Doublethink means the power of holding two contradictory beliefs in one’s mind simultaneously...
Spesso noi agiamo senza pensare, quasi avessimo un pensiero incorporato...
... the steps should be conceived as tacit. To get in your car and drive away entails a long series of steps—take out  your keys, unlock and open the door, sit down, put the key in the ignition, and so on…
Ecco allora la versione psicologica del modello “rational irrational”…
… Step 1: Be rational on topics where you have no emotional attachment to a particular answer. Step 2: On topics where you have an emotional attachment to a particular answer, keep a “lookout” for questions where false beliefs imply a substantial material cost for you. Step 3: If you pay no substantial material costs of error, go with the flow; believe whatever makes you feel best. Step 4: If there are substantial material costs of error, raise your level of intellectual self-discipline in order to become more objective. Step 5: Balance the emotional trauma of heightened objectivity—the progressive shattering of your comforting illusions—against the material costs of error…
Se il costo non è eccessivo conviene lasciare la razionalità in standby. Non c’è nemmeno bisogno di averne coscienza.
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Vediamo alcuni “case study”.
John Noss nel suo libro sulle religioni riporta una diatriba religiosa tipica dello giainismo indiano: è lecito indossare qualche vestito oppure per il fedele è d’obbligo la nudità assoluta?…
… Early in the history of the faith the Jains divided on the question of wearing clothes. The Shvetambaras or the “white-clad” were the liberals who took their stand on wearing at least one garment, whereas the stricter and more conservative Digambaras got their name from their insistence on going about, whenever religious duty demanded it, “clad in atmosphere.” Mahavira [the last of the founding prophets of Jainism] did not wear clothes, they pointed out, so why, when there is a religious reason for not wearing clothes, should they? The Shvetambaras were in the north and yielded a bit both to the cold winds and to the social and cultural influences of the Ganges River plain. The Digambaras, not looked at askance by the Dravidian residents of their southland, have more easily maintained the earlier, sterner attitudes down the years…
Guarda caso i teologi operanti nelle regioni più fresche ammettevano l’uso di un vestiario. Evidentemente, laddove tira vento la bella credenza della nudità assoluta è troppo costosa.
Gaetano Mosca fece notare che la Jihad prometteva al martire una condizione privilegiata in Paradiso. Domanda: perché mai allora le truppe mussulmane si arrendevano quando erano spacciate? Evidentemente la bella credenza del martire in Paradiso, in quel caso era troppo costosa…
… Mohammed, for instance, promises paradise to all who fall in a holy war. Now if every believer were to guide his conduct by that assurance in the Koran, every time a Mohammedan army found itself faced by unbelievers it ought either to conquer or to fall to the last man. It cannot be denied that a certain number of individuals do live up to the letter of the Prophet’s word, but as between defeat and death followed by eternal bliss, the majority of Mohammedans normally elect defeat… As long as they are at peace or militarily have the upper hand, the belief that Allah brings the fallen to paradise gives psychological comfort with little risk. When they are losing, however, soldiers’ “standby” rationality kicks in…
In india vige la consuetudine del Sati: la vedova deve salire sulla pira che brucia il cadavere del marito e morire con lui. Tutti aderiscono a questa bella credenza ma al dunque ben poche la praticano. E’ troppo costosa!…
… On some interpretations of Hinduism, a widow must join her deceased husband on his funeral pyre, a practice known as sati. Fulfilling this duty supposedly has great rewards in the afterlife. On the surface, sati looks like a clear case of persistent irrationality despite deadly incentives. But the reality, explains anthropologist Robert Edgerton, is different. Few Hindu widows ever complied with their putative duty: “Even in Bengal where sati was most common, only a small minority of widows—less than 10 percent—chose sati although the prospect of widowhood was dismal at best.”47 Some of these were frankly murdered by their husband’s relatives. When the widow refused the pyre, she was not allowed to resume a normal life….
Un altro caso è quello del rapporto tra comunisti e scienza….
… Marxist philosophers have dogmatic objections to modern biology and physics. Genetics is “a bourgeois fabrication designed to undermine the true materialist theory of biological development,” and relativity theory and quantum mechanics are “idealist positions” that “contravene[d] the materialism espoused by Lenin in Materialism and Empirio-Criticism.”… In biology, Stalin and other prominent Marxist leaders elevated the views of the quack antigeneticist Trofim Lysenko to state-supported orthodoxy… Internationally respected physicists ran the Soviet atomic project, not Marxist ideologues…
In biologia si poteva fare dell’ideologia ma in fisica c’era la bomba da costruire, la ricerca doveva essere seria.
Tra dieci anni la povertà nel mondo sarà aumentata o diminuita? Un conto è rispondere liberamente, un conto è scommettere una somma rilevante. Gli scommettitori sono più riflessivi e moderati…
… We encounter the price-sensitivity of irrationality whenever someone unexpectedly offers us a bet based on our professed beliefs.59 Suppose you insist that poverty in the Third World is sure to get worse in the next decade. A challenger immediately retorts, “Want to bet?…
Put up or schut up”.
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Colleghiamo ora quanto detto con la politica. E’ chiaro che le nostre credenze politiche ci costano poco… 
… Suppose a referendum determines whether we have policy A or policy B. A is $10,000 better for you. What is the material cost of believing the opposite and voting accordingly? The naive answer of $10,000 is wrong unless your vote is “decisive”; that is, if it reverses or flips the electoral outcome. This is possible only if the choices of all other voters exactly balance. Thus, in elections with millions of voters, the probability that your erroneous policy beliefs cause unwanted policies is approximately zero…
Il nostro voto incide praticamente zero. Non solo, noi, più o meno consciamente, sappiamo che incide praticamente zero, basta vedere come reagiamo ad una poll tax…
… How many times have you heard, “Every vote matters”? But people are less credulous than they sound. The infamous poll tax—which restricted the vote to those willing to pay for it—provides a clean illustration. If individuals acted on the belief that one vote makes a big difference, they would be willing to pay a lot to participate… Intuitively, if one vote cannot change policy outcomes, the price of irrationality is zero. This zero makes rational irrationality a politically pregnant idea…
Riassumendo: 1) alcune credenze ci piacciono più di altre 2) in politica credere quel che ci piace ci costa poco per due motivi: il nostro voto incide poco e le eventuali conseguenze negative si ripartiscono su una grande popolazione, 3) gli elettori sono irrazionali (o stupidi che dir si voglia).
Mercato e politica sono molto differenti in questo senso…
… The same people who practice intellectual self-discipline when they figure out how to commute to work, repair a car, buy a house, or land a job “let themselves go” when they contemplate the effects of protectionism, gun control, or pharmaceutical regulation…
Detto esplicitamente: secondo voi chi è contro la pena di morte si studia le statistiche per soppesarne la deterrenza? E chi si oppone alla libera circolazione delle armi studia forse la complicata relazione tra armi e crimini?…
… Consider how the typical person forms beliefs about the deterrent effect of the death penalty. Ordinary intellectual self-discipline requires you to look at the evidence before you form a strong opinion. In practice, though, most people with definite views on the effectiveness of the death penalty never feel the need to examine the extensive empirical literature. Instead, they start with strong emotions about the death penalty, and heatedly “infer” its effect… The death penalty is an unusually emotional issue, but its template fits most politically relevant beliefs…
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Alcuni studiosi ritengono però che noi siamo irrazionali indipendentemente dagli incentivi che ci inducono ad esserlo. In altri termini, gli incentivi non contano…
… Researchers at the intersection of psychology and economics often take a more radical position: Not only are people irrational, but their irrationality stays the same or increases as its cost rises…
Il Nobel Richard Thaler – appoggiandosi al lavoro di Hogarth e Camerer - è forse il massimo rappresentante di questo indirizzo, e in effetti alcuni studi di laboratorio sembrerebbero svalutare la portata degli incentivi.
Altri però vanno più nella direzione del senso comune segnalando come gli scommettitori siano più attenti dei non-scommettitori…
… a recent paper finds that people get less overconfident when they have to bet real money on their beliefs… Hoelzl and Rustichini (2005)…
Di solito gli incentivi sono problematici in laboratorio, ma la dimensione del laboratorio riesce a catturare la realtà?…
… Economic actors in their “natural habitat” look considerably more rational than they do in the lab…
Sembrerebbe proprio di no, almeno secondo Harrison/List (2004) e List (2003).
L’osservazione in laboratorio è limitata…
… few experiments on human beings last more than a few hours…
Thaler, per esempio, sostiene che gli incentivi valgono per i compiti facile e non valgono per quelli difficili. Ma il professionista è tale proprio perché trasforma il difficile in facile…
… A common summary of the experimental literature is that incentives improve performance on easy problems but hurt performance on hard problems… the difficulty of a problem falls if you have more time and flexibility to solve it. Hard problems naturally decay into easier problems. Once they are easy enough, incentives work…
La sperimentazione sul campo di John List è tesa ad evidenziare quanto i professionisti siano sensibili agli incentivi.
Per valutare l’efficacia degli incentivi guardate poi alla vostra esperienza personale. Vi sembra davvero che non pesino?…
… The typical person faces both practical questions—doing his job, buying groceries, or driving—and impractical ones—like politics and religion. It is hard to deny that both intellectual effort and accuracy are much higher for practical questions…
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Il modello “rational irrational” attinge al modello del “voto espressivo” di Geoffrey Brennan e Loren Lomasky. I due autori, contrariamente a molti economisti, non assumono il voto come uno strumento per ottenere qualcosa…
… Brennan and Lomasky point to the expressive function of voting. Fans at a football game cheer not to help the home team win, but to express their loyalty. Similarly, citizens might vote not to help policies win, but to express their patriotism, their compassion, or their devotion to the environment. This is not hair-splitting. One implication is that inefficient policies like tariffs or the minimum wage might win because expressing support for them makes people feel good about themselves…
Il voto consente all’elettore di esprimersi, di sfogarsi.
Pensate solo al razzismo/sessismo: in politica esce continuamente (è uno sfogo ai disagi, la caccia al capro espiatorio) ma sul mercato molto meno per il fatto di avere un costo: potremmo pagare molto caro la rinuncia a lavorare con un ebreo o una donna in gamba…
… Case in point: When economists analyze discrimination, they emphasize the financial burden of being a bigot.89 In politics, the social cost of prejudice remains, but the private cost vanishes due to voters’ low probability of decisiveness…
Ma i due modelli non sono identici
… The key difference is the mechanism. In expressive voting theory, voters know that feel-good policies are ineffective. Expressive voters do not embrace dubious or absurd beliefs about the world. They simply care more about how policies sound than how they work. The expressive protectionist thinks: “Sure, protectionism makes Americans poorer. But who cares, as long as I can wave the flag and chant ‘U.S.A.! U.S.A.!’ ” In contrast, rationally irrational voters believe that feel-good policies work…
Nel modello “rational irrational” lo “stupido” crede a quel che pensa, è lì che sta la soddisfazione. La razionalità viene sospesa a priori e si va a ruota libera.
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Come concludere? Direi così: la stupidità dell’elettore non è affatto un mistero. Essere stupidi è bello e in politica – diversamente che sul mercato - costa poco…
… Economists have often been criticized for evading the differences between political and market behavior.98 But this is a failure of economists rather than a failure of economics. Economists should never have expected political behavior to parallel market behavior in the first place. Irrationality in politics is not a puzzle. It is precisely what an economic theory of irrationality predicts…
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