Är rationella val trots allt möjliga?

Beteendeekonomins landvinningar har nog fått en och annan att tvivla på att människor är förmögna att göra rationella val. Men en ny analys, ”Rational Choices: An Ecological Approach”, ger vid handen att det under vissa inte helt orimliga villkor mycket väl kan vara så att rationella val trots allt är möjliga. Det har med ekologisk rationalitet att göra:

We address the oft-repeated criticism that the demands which the rational choice approach makes on the knowledge and cognition of a decision-maker (DM) are way beyond the capabilities of typical human intelligence. Our key finding is that it may be possible to arrive at this ideal of rationality by means of cognitively less demanding, heuristic-based ecological reasoning that draws on information about others’ choices in the DM’s environment. Formally, we propose a choice procedure under which, in any choice problem, the DM, first, uses this information to shortlist a set of alternatives. The DM does this shortlisting by a mental process of categorization, whereby she draws similarities with certain societal members—the ingroup—and distinctions from others—the outgroup—and considers those alternatives that are similar (dissimilar) to ingroup (outgroup) members’ choices. Then, she chooses from this shortlisted set by applying her preferences, which may be incomplete owing to limitations of knowledge. We show that, if a certain homophily condition connecting the DM’s preferences with her ingroup–outgroup categorization holds, then the procedure never leads the DM to making bad choices. If, in addition, a certain shortlisting consistency condition holds vis-a-vis non-comparable alternatives under the DM’s preferences, then the procedure results in rational choices.

Detta teoretiskt grundade resultat understryker det vådliga i att utifrån experimentella resultat av individer, utan beaktande av den vidare beslutsmiljö i vilken de verkar, dra slutsatser om rationalitet och, särskilt, slutsatser om paternalism.

Se tidigare inlägg på liknande tema:

IQ ger ekonomisk rationalitet

Det verkar som om riktigt smarta män beter sig mer som homo economicus än andra män, enligt den nya studien ”IQ, Expectations and Choice”:

Men above the median IQ (high-IQ men) display 50% lower forecast errors for inflation than other men. … High-IQ men are also less likely to round and to forecast implausible values. In terms of choice, only high-IQ men increase their propensity to consume when expecting higher inflation as the consumer Euler equation prescribes. High-IQ men are also forward-looking — they are more likely to save for retirement conditional on saving. Education levels, income, socio-economic status, and employment status, although important, do not explain the variation in expectations and choice by IQ.

Som alla vet är det svårt att utfärda ekonomiska prognoser – många tror (felaktigt) att de flesta nationalekonomer är och bör vara prognosmakare – men om man ska anställa folk som ska försöka sig på det ter det sig klokt att leta efter personer med hög IQ.

Tänk inte så mycket

Ett tänkvärt (!) budskap:

Unthinking is the ability to apply years of learning at the crucial moment by removing your thinking self from the equation. Its power is not confined to sport: actors and musicians know about it too, and are apt to say that their best work happens in a kind of trance. Thinking too much can kill not just physical performance but mental inspiration. … In less dramatic ways the same principle applies to all of us. A fundamental paradox of human psychology is that thinking can be bad for us. When we follow our own thoughts too closely, we can lose our bearings, as our inner chatter drowns out common sense.

Detta stämmer väl överens med mina egna erfarenheter. När jag tänker intensivt kommer jag sällan framåt – de insikter jag hoppas ska dyka upp blockeras på något sätt. Det är oftast när jag gör något helt annat, när hjärnan är i ett annat tillstånd, som de bästa idéerna infinner sig (i regel när jag simmar).

Det får mig också att tänka på (!) ”lyckoparadoxen”: att den som medvetet strävar efter lycka har svårt att finna den. Som John Stuart Mill uttrycker det i sin självbiografi:

But I now thought that this end [one’s happiness] was only to be attained by not making it the direct end. Those only are happy (I thought) who have their minds fixed on some object other than their own happiness. … Aiming thus at something else, they find happiness along the way. … Ask yourself whether you are happy, and you cease to be so.

Tänk nu bara inte för mycket på detta.

Kunskap och inbillad kunskap om genmodifierad mat

I en demokrati har alla en röst oavsett vilken kunskap de har om olika sakfrågor. Detta har bekymrat vissa (t ex John Stuart Mill). Det är inte utan att man blir bekymrad när man tar del av resultaten i den nya studien ”Extreme Opponents of Genetically Modified Foods Know the Least but Think They Know the Most”:

In a nationally representative sample of US adults, we find that as extremity of opposition to and concern about genetically modified foods increases, objective knowledge about science and genetics decreases, but perceived understanding of genetically modified foods increases. Extreme opponents know the least, but think they know the most. Moreover, the relationship between self-assessed and objective knowledge shifts from positive to negative at high levels of opposition. Similar results were obtained in a parallel study with representative samples from the United States, France and Germany, and in a study testing attitudes about a medical application of genetic engineering technology (gene therapy).

Resultaten illustreras i denna figur, som visar de predikterade sambanden mellan hur starkt man motsätter sig genmodifierad mat och objektiv respektive självbedömd kunskap (där de skuggade områdena visar ett 95-procentigt konfidentsintervall):

skärmklipp 2019-01-20 10.24.11

Det är lätt att komma att tänka på Dunning-Kruger-effekten.

Nå, lösningen på problemet är nog inte att kräva kunskapstester för väljare, men denna typ av starka uppfattningar, baserade på en felaktig tro på kunnande, utgör onekligen en utmaning för de av oss som vill se rationella beslut i viktiga frågor. Om det inte går att utbilda okunniga men engagerade personer är frågan om deras inflytande över beslutsfattandet kan minimeras på något sätt.

Rationalitet som process

Något som förenar många neoklassiska nationalekonomer och beteendeekonomer är förståelse av rationalitet som ett statiskt fenomen. Ännu en gång utmanar Mario Rizzo och Glen Whitman denna förståelse av rationalitet, i artikeln ”Rationality as a Process”:

Real human beings do not make decisions instantaneously and without error. Nor do they know all of their goals, and their fully specified willingness to trade them off against each other, prior to making any decisions. Nor do they hold beliefs that are instantaneously consistent with each other and the world. Forming one’s preferences and beliefs is a process, and therefore it seems natural to evaluate them in terms of that process. In doing so, we find that the static approach implicitly conflates rationality with a form of omniscience. If our normative standard is the flawless or optimal solution to problems as defined and understood by the analyst, we will no doubt find many violations of “rationality.” However, these may not be the agent’s problems. They may be problems of inadequate and superficial analysis, driven by the analyst’s static conception of rationality. As an alternative, we suggest the possibility of a process-driven account of rationality that includes a role for intrapersonal bargaining and arbitrage, dialectical reasoning, responsiveness of alleged biases to cost, and learning in response to error. Such an account would surely be preferable on normative grounds, but it also holds the promise of better positive accounts of human behavior.

Analysen tycks mig rationell – och viktig, ty med denna mindre snäva förståelse av rationalitet blir policyimplikationerna också mindre interventionistiska.

Se även tidigare inlägg på liknande tema: ”Den nya paternalismen problematiserad”, ”Beteendeekonomi för politiker”, ”Mot moralisk styrning”, ”Pigou i praktiken” och ”Leder mjuk paternalism till hård?”.

När känslor styr människors uppfattningar

John Stuart Mill argumenterade för följande i The Subjection of Women:

That the principle which regulates the existing social relations between the two sexes—the legal subordination of one sex to the other—is wrong in itself, and now one of the chief hindrances to human improvement; and that it ought to be replaced by a principle of perfect equality, admitting no power or privilege on the one side, nor disability on the other.

Men han insåg ett huvudproblem – nämligen att många intog en attityd i frågan på känslomässig grund, vilket gör argument i sak oförmögna att förändra attityden. Han beskriver det här problemet i början av boken:

So long as an opinion is strongly rooted in the feelings, it gains rather than loses in stability by having a preponderating weight of argument against it. For if it were accepted as a result of argument, the refutation of the argument might shake the solidity of the conviction; but when it rests solely on feeling, the worse it fares in argumentative contest, the more persuaded its adherents are that their feeling must have some deeper ground, which the arguments do not reach; and while the feeling remains, it is always throwing up fresh intrenchments of argument to repair any breach made in the old. And there are so many causes tending to make the feelings connected with this subject the most intense and most deeply-rooted of all those which gather round and protect old institutions and customs, that we need not wonder to find them as yet less undermined and loosened than any of the rest by the progress of the great modern spiritual and social transition; nor suppose that the barbarisms to which men cling longest must be less barbarisms than those which they earlier shake off.

Vilken utmaning för den förnuftsinriktade människa som försöker förändra en allmänt spridd attityd genom argument! Men å andra sidan oerhört viktig att känna till och beakta när man ger sig in i den offentliga debatten. Utmaningen är att stå kvar på solid intellektuell grund i sina uppfattningar, att ha kvar viljan och energin att sprida dem vidare – men att också i detta använda sig av medel som talar till känslor.

Två typer av ekologisk rationalitet

Det neoklassiska rationalitetsbegreppet har utmanats av beteendekonomin, vars betoning av icke-rationalitet i en hel del mänskligt beslutsfattande har fått stor uppmärksamhet och stort genomslag. Ett sätt att beskriva denna utmaning är att mer realistiska, på psykologisk analys grundade antaganden om vad som kännetecknar en ekonomisk beslutsfattare har kommit att föredras. Men det är inte självklart hur psykologi och nationalekonomi ska kombineras.

I den just publicerade artikeln ”Two Types of Ecological Rationality: Or How to Best Combine Psychology and Economics” utvecklar Erwin Dekker och Blaž Remic vad som skiljer och förenar två sådana ansatser, som båda betonar förekomsten av ekologisk rationalitet (ER). Den ena, ER1, representeras av Gerd Gigerenzer och den andra, ER2, av Ekonomipristagaren Vernon Smith. Dessa står i viss kontrast mot det dominerande beteendeekonomiska synsättet, som i artikeln kallas för ”heuristics-and-biases”-programmet (H&B):

H&B has become widely accepted as the standard way of integrating psychology and economics (Angner 2018). The H&B program presents itself as a serious challenge to the neoclassical picture of the rational economic man, and argues that a serious reconsideration of rationality is necessary, since individuals are only boundedly rational (Tversky and Kahneman 1974; Kahneman 2003; Camerer, Loewenstein, and Rabin 2004; Mullainathan and Thaler 2000). The proponents of ecological rationality do not seek to challenge this claim of bounded rationality. They fully accept it – in fact, they sometimes go even further in emphasizing the cognitive limitations of individuals. However, they argue that in the interaction with their (social) environment individuals are nonetheless able to make reasonably good, or as good as rational, decisions, because they are able to use the environment to their advantage through cues or institutional features of that environment.

Men det finns skillnader mellan ER1 och ER2:

ER1, part of Gigerenzer’s fast-and-frugal heuristics approach, is based on the picking up of cues in the environment, which are inputs for heuristics used to arrive at quick decisions. The individual is ‘ecologically rational’ to the extent that the strategies, the heuristics, used are well adapted to her environment. ER2, part of the market-experimental approach developed by Smith, Plott and others, is based on institutional constraints and social and cultural norms, which help the individual to navigate his social environment. The system is ‘ecologically rational’ to the extent that it facilitates this navigation by the individual by means of embedded norms, learning or feedback mechanisms, and leads to outcomes that are efficient in the aggregate. Both the institutional rules and in particular the social norms emerge in the process of social interaction, and represent the cognitive content that is off-loaded to the environment.

I denna figur kontrasteras de tre ansatserna för att kombinera psykologi med nationalekonomi:

Skärmklipp 2018-12-30 00.40.23

Slutsatsen, vad gäller implikationerna för det beteendeekonomiska forskningsprogrammet, är intressant:

It is tempting to accept the standard narrative that modern behavioral economics is the reintroduction of psychology into economics. However, that narrative relies heavily on the idea that there is one economics and one psychology. In this paper, we demonstrate that this narrative is severely complicated when we look at the two conceptions of ecological rationality, which are offered as alternatives to modern behavioral economics and accounts of ‘bounded rationality’. As we have demonstrated, these present two alternative combinations of economics and psychology. The methodological question for economists, therefore, shifts from a concern over whether economics needs psychology to what type of integration of the two fields is desirable and fruitful.  … To move forward the fruitful discussion between these different programs, it is important to realize that such deep methodological differences exist. Psychology is and will remain relevant to economics, as is by now broadly accepted. But importing parts of another discipline, or even merging the two, should not and cannot occur without a good understanding of which goods we are importing.

Själv är jag (likt David Levine) mindre övertygad om värdet av integration av psykologi och nationalekonomi, men givet att man är positivt inställd till en sådan utveckling kan denna artikel erbjuda grund för en del nyttiga reflexioner. Inte minst finner jag det fascinerande att, likt Gigerenzer, peka på att det finns kognitiva genvägar och att, likt Smith, peka på att det finns informella och formella institutioner som har förmåga att få människor att nästan förefalla rationella.

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