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Monday, January 17, 2022

Rational choice theory

Rational choice theory refers to a set of guidelines that help understand economic and social behaviour. The theory originated in the eighteenth century and can be traced back to political economist and philosopher, Adam Smith. The theory postulates that an individual will perform a cost-benefit analysis to determine whether an option is right for them. It also suggests that an individual's self-driven rational actions will help better the overall economy. Rational choice theory looks at three concepts: rational actors, self interest and the invisible hand.

Rationality can be used as an assumption for the behaviour of individuals in a wide range of contexts outside of economics. It is also used in political science, sociology, and philosophy.

Overview

The basic premise of rational choice theory is that the decisions made by individual actors will collectively produce aggregate social behaviour. The theory also assumes that individuals have preferences out of available choice alternatives. These preferences are assumed to be complete and transitive. Completeness refers to the individual being able to say which of the options they prefer (i.e. individual prefers A over B, B over A or are indifferent to both). Alternatively, transitivity is where the individual weakly prefers option A over B and weakly prefers option B over C, leading to the conclusion that the individual weakly prefers A over C. The rational agent will then perform their own cost-benefit analysis using a variety of criterion to perform their self-determined best choice of action.

One version of rationality is instrumental rationality, which involves achieving a goal using the most cost effective method without reflecting on the worthiness of that goal. Duncan Snidal emphasises that the goals are not restricted to self-regarding, selfish, or material interests. They also include other-regarding, altruistic, as well as normative or ideational goals.

Rational choice theory does not claim to describe the choice process, but rather it helps predict the outcome and pattern of choice. It is consequently assumed that the individual is self-interested or being homo economicus. Here, the individual comes to a decision that maximizes personal advantage by balancing costs and benefits. Proponents of such models, particularly those associated with the Chicago school of economics, do not claim that a model's assumptions are an accurate description of reality, only that they help formulate clear and falsifiable hypotheses. In this view, the only way to judge the success of a hypothesis is empirical tests. To use an example from Milton Friedman, if a theory that says that the behavior of the leaves of a tree is explained by their rationality passes the empirical test, it is seen as successful.

Without explicitly dictating the goal or preferences of the individual, it may be impossible to empirically test or invalidate the rationality assumption. However, the predictions made by a specific version of the theory are testable. In recent years, the most prevalent version of rational choice theory, expected utility theory, has been challenged by the experimental results of behavioral economics. Economists are learning from other fields, such as psychology, and are enriching their theories of choice in order to get a more accurate view of human decision-making. For example, the behavioral economist and experimental psychologist Daniel Kahneman won the Nobel Memorial Prize in Economic Sciences in 2002 for his work in this field.

Rational choice theory has proposed that there are two outcomes of two choices regarding human action. Firstly, the feasible region will be chosen within all the possible and related action. Second, after the preferred option has been chosen, the feasible region that has been selected was picked based on restriction of financial, legal, social, physical or emotional restrictions that the agent is facing. After that, a choice will be made based on the preference order.

The concept of rationality used in rational choice theory is different from the colloquial and most philosophical use of the word. In this sense, "rational" behaviour can refer to "sensible", "predictable", or "in a thoughtful, clear-headed manner." Rational choice theory uses a much more narrow definition of rationality. At its most basic level, behavior is rational if it is goal-oriented, reflective (evaluative), and consistent (across time and different choice situations). This contrasts with behavior that is random, impulsive, conditioned, or adopted by (unevaluative) imitation.

Early neoclassical economists writing about rational choice, including William Stanley Jevons, assumed that agents make consumption choices so as to maximize their happiness, or utility. Contemporary theory bases rational choice on a set of choice axioms that need to be satisfied, and typically does not specify where the goal (preferences, desires) comes from. It mandates just a consistent ranking of the alternatives. Individuals choose the best action according to their personal preferences and the constraints facing them. E.g., there is nothing irrational in preferring fish to meat the first time, but there is something irrational in preferring fish to meat in one instant and preferring meat to fish in another, without anything else having changed.

Actions, assumptions, and individual preferences

The basic premise of rational choice theory is that the decisions made by individual actors will collectively produce aggregate social behaviour. Thus, each individual makes a decision based on their own preferences and the constraints (or choice set) they face.

Rational choice theory can be viewed in different contexts. At an individual level, the theory suggests that the agent will decide on the action (or outcome) they most prefer. If the actions (or outcomes) are evaluated in terms of costs and benefits, the choice with the maximum net benefit will be chosen by the rational individual. Rational behaviour is not solely driven by monetary gain, but can also be driven by emotional motives.

The theory can be applied to general settings outside of those identified by costs and benefits. In general, rational decision making entails choosing among all available alternatives the alternative that the individual most prefers. The "alternatives" can be a set of actions ("what to do?") or a set of objects ("what to choose/buy"). In the case of actions, what the individual really cares about are the outcomes that results from each possible action. Actions, in this case, are only an instrument for obtaining a particular outcome.

Formal statement

The available alternatives are often expressed as a set of objects, for example a set of j exhaustive and exclusive actions:

For example, if a person can choose to vote for either Roger or Sara or to abstain, their set of possible alternatives is:

The theory makes two technical assumptions about individuals' preferences over alternatives:

  • Completeness – for any two alternatives ai and aj in the set, either ai is preferred to aj, or aj is preferred to ai, or the individual is indifferent between ai and aj. In other words, all pairs of alternatives can be compared with each other.
  • Transitivity – if alternative a1 is preferred to a2, and alternative a2 is preferred to a3, then a1 is preferred to a3.

Together these two assumptions imply that given a set of exhaustive and exclusive actions to choose from, an individual can rank the elements of this set in terms of his preferences in an internally consistent way (the ranking constitutes a partial ordering), and the set has at least one maximal element.

The preference between two alternatives can be:

  • Strict preference occurs when an individual prefers a1 to a2 and does not view them as equally preferred.
  • Weak preference implies that individual either strictly prefers a1 over a2 or is indifferent between them.
  • Indifference occurs when an individual neither prefers a1 to a2, nor a2 to a1. Since (by completeness) the individual does not refuse a comparison, they must therefore be indifferent in this case.

Research that took off in the 1980s sought to develop models that drop these assumptions and argue that such behaviour could still be rational, Anand (1993). This work, often conducted by economic theorists and analytical philosophers, suggests ultimately that the assumptions or axioms above are not completely general and might at best be regarded as approximations.

Additional assumptions

  • Perfect information: The simple rational choice model above assumes that the individual has full or perfect information about the alternatives, i.e., the ranking between two alternatives involves no uncertainty.
  • Choice under uncertainty: In a richer model that involves uncertainty about the how choices (actions) lead to eventual outcomes, the individual effectively chooses between lotteries, where each lottery induces a different probability distribution over outcomes. The additional assumption of independence of irrelevant alternatives then leads to expected utility theory.
  • Inter-temporal choice: when decisions affect choices (such as consumption) at different points in time, the standard method for evaluating alternatives across time involves discounting future payoffs.
  • Limited cognitive ability: identifying and weighing each alternative against every other may take time, effort, and mental capacity. Recognising the cost that these impose or cognitive limitations of individuals gives rise to theories of bounded rationality.

Alternative theories of human action include such components as Amos Tversky and Daniel Kahneman's prospect theory, which reflects the empirical finding that, contrary to standard preferences assumed under neoclassical economics, individuals attach extra value to items that they already own compared to similar items owned by others. Under standard preferences, the amount that an individual is willing to pay for an item (such as a drinking mug) is assumed to equal the amount they are willing to be paid in order to part with it. In experiments, the latter price is sometimes significantly higher than the former (but see Plott and Zeiler 2005, Plott and Zeiler 2007 and Klass and Zeiler, 2013). Tversky and Kahneman do not characterize loss aversion as irrational. Behavioral economics includes a large number of other amendments to its picture of human behavior that go against neoclassical assumptions.

Utility maximization

Often preferences are described by their utility function or payoff function. This is an ordinal number that an individual assigns over the available actions, such as:

The individual's preferences are then expressed as the relation between these ordinal assignments. For example, if an individual prefers the candidate Sara over Roger over abstaining, their preferences would have the relation:

A preference relation that as above satisfies completeness, transitivity, and, in addition, continuity, can be equivalently represented by a utility function.

Benefits

The rational choice approach allows preferences to be represented as real-valued utility functions. Economic decision making then becomes a problem of maximizing this utility function, subject to constraints (e.g. a budget). This has many advantages. It provides a compact theory that makes empirical predictions with a relatively sparse model - just a description of the agent's objectives and constraints. Furthermore, optimization theory is a well-developed field of mathematics. These two factors make rational choice models tractable compared to other approaches to choice. Most importantly, this approach is strikingly general. It has been used to analyze not only personal and household choices about traditional economic matters like consumption and savings, but also choices about education, marriage, child-bearing, migration, crime and so on, as well as business decisions about output, investment, hiring, entry, exit, etc. with varying degrees of success.

In the field of political science rational choice theory has been used to help predict human decision making and model for the future; therefore it is useful in creating effective public policy, and enables the government to develop solutions quickly and efficiently.

Despite the empirical shortcomings of rational choice theory, the flexibility and tractability of rational choice models (and the lack of equally powerful alternatives) lead to them still being widely used.

Applications

Rational choice theory has become increasingly employed in social sciences other than economics, such as sociology, evolutionary theory and political science in recent decades. It has had far-reaching impacts on the study of political science, especially in fields like the study of interest groups, elections, behaviour in legislatures, coalitions, and bureaucracy. In these fields, the use of the rational choice theory to explain broad social phenomena is the subject of controversy.

Rational choice theory in politics

The relationship between the rational choice theory and politics takes many forms, whether that be in voter behaviour, the actions of world leaders or even the way that important matters are dealt with.

Voter behaviour shifts significantly thanks to rational theory, which is ingrained in human nature, the most significant of which occurs when there are times of economic trouble. This was assessed in detail by Anthony Downs who concluded that voters were acting on thoughts of higher income as a person ‘votes for whatever party he believes would provide him with the highest utility income from government action’. This is a significant simplification of how the theory influences people's thoughts but makes up a core part of rational theory as a whole. In a more complex fashion, voters will react often radically in times of real economic strife, which can lead to an increase in extremism. The government will be made responsible by the voters and thus they see a need to make a change. Some of the most infamous extremist parties came to power on the back of economic recessions, the most significant being the far right Nazi Party in Germany, who used the hyperinflation at the time to gain power rapidly, as they promised a solution and a scapegoat for the blame. There is a trend to this, as a comprehensive study carried out by three political scientists concluded, as a ‘turn to the right’ occurs and it is clear that it is the work of the rational theory because within ten years the politics returns to a more common state.

Anthony Downs also suggested that voting involves a cost/benefit analysis in order to determine how a person would vote. He argues that someone will vote if B+D>C, where B= The benefit of the voter winning, D= Satisfaction and C being the cost of voting. It is from this that we can determine that parties have moved their policy outlook to be more centric in order to maximise the amount of voters they have for support. This is becoming more and more prevalent with every election as each party tries to appeal to a broader range of voters. This is especially prevalent as there has been a decline in party memberships, meaning that each party has much less guaranteed votes. In the last 10 years there has been a 37% decrease in party memberships, with this trend having started soon after the Second World War. This shows that the electorate a leaning towards making informed, rational decisions as opposed to relying on a pattern of behaviours. Overall the electorate are becoming more inclined to vote based on recency factors in order to protect their interests and maximise their utility.

Meaning Rational Choice Theory has the ability to be used in modelling and forecasting, owing to its nature being derived from economic thought to explain human behaviour. This is useful in politics as the theory can quantify human decision making and behaviour into data that can be interpreted, helping to predict behaviours and outcomes. Therefore enabling the ability to direct and shape political thinking and campaigns, maximizing utility. 

As useful as the use of empirical data is in building a clear picture of voting behaviour it doesn't full show all aspects of political decision making whether that be from the electorate or the policy makers. As  brings the idea of commitment as a key concept to the behaviour of political agents. That it is not only self interest that is the outcome of personal cost benefit analysis but it is also the idea of shared interests. That the key idea of utility needs to be defined not only as material utility but also as experienced utility, these expansions to classical rational choice theory could then begin to remove the weakness in regards to morals of the agents which it aims to interoperate their actions.

A downfall of rational choice theory in a political sense, is that is the pursuit of individual goals can lead to collectively irrational outcomes. This problem of collective action can disincentivise people to vote. Even though a group of people may have common interests, they also have conflicting ones that cause misalignment within the group and therefore an outcome that does not benefit the group as a whole as people want to pursue their own individual interests. This problem is rooted in Rational Choice theory because of the theories emphasis on the rational agents performing their own cost-benefit analysis to maximize their self-interests. 

An example of this can be shown by some of the world’s most troubling problems, such as the climate crisis. Nation states can be seen as rational as they fulfil their own interests of economic growth, however, this economic growth often leads to pollution as increasing a nation’s factors of production takes a toll on the environment. It is irrational for a state to forego this economic growth as the cost of pollution does not entirely fall on them, as one state’s carbon emissions would not entirely affect that state alone, as it impacts elsewhere. This means the benefit of the economic growth outweighs the cost of pollution, according to the theory of Rational Choice. However, If all countries made this rational calculation it would lead to a massive amount of pollution. Making the outcome of a rational choice, a collectively irrational outcome.

Rational choice theory in international relations

Rational choice theory has become one of the major approaches in the study of international relations. Its proponents typically assume that states are the key actors in world politics and that they seek goals such as power, security, or wealth. They have applied rational choice theory to policy issues ranging from international trade and international cooperation to sanctions, arms competition, (nuclear) deterrence, and war.

For example, some scholars have examined how states can make credible threats to deter other states from a (nuclear) attack. Others have explored under what conditions states wage war against each other. Yet others have investigated under what circumstances the threat and imposition of international economic sanctions tend to succeed and when they are likely to fail.

Rational Choice theory in Social Interactions

Rational Choice Theory and Social exchange theory involves looking at all social relations in the form of costs and rewards, both tangible and non tangible.

According to Abell, Rational Choice Theory is "understanding individual actors... as acting, or more likely interacting, in a manner such that they can be deemed to be doing the best they can for themselves, given their objectives, resources, circumstances, as they seem them". Rational Choice Theory has been used to comprehend the complex social phenomena, of which derives from the actions and motivations of an individual. Individuals are often highly motivated by the wants and needs.

By making calculative decisions, it is considered as rational action. Individuals are often making calculative decisions in social situations by weighing out the pros and cons of an action taken towards a person. The decision to act on a rational decision is also dependent on the unforeseen benefits of the friendship. Homan mentions that actions of humans are motivated by punishment or rewards. This reinforcement through punishments or rewards determines the course of action taken by a person in a social situation as well. Individuals are motivated by mutual reinforcement and are also fundamentally motivated by the approval of others. Attaining the approval of others has been a generalized character, along with money, as a means of exchange in both Social and Economic exchanges. In Economic exchanges, it involves the exchange of goods or services. In Social exchange, it is the exchange of approval and certain other valued behaviors.

Rational Choice Theory in this instance, heavily emphasizes the individual's interest as a starting point for making social decisions. Despite differing view points about Rational choice theory, it all comes down to the individual as a basic unit of theory. Even though sharing, cooperation and cultural norms emerge, it all stems from an individual's initial concern about the self.

Social Exchange and Rational Choice Theory both comes down to an individual's efforts to meet their own personal needs and interests through the choices they make. Even though some may be done sincerely for the welfare of others at that point of time, both theories point to the benefits received in return. These returns may be received immediately or in the future, be it tangible or not.

Coleman discussed a number of theories to elaborate on the premises and promises of rational choice theory. One of the concepts that He introduced was Trust. It is where "individuals place trust, in both judgement and performance of others, based on rational considerations of what is best, given the alternatives they confront". In a social situation, there has to be a level of trust among the individuals. He noted that this level of trust is a consideration that an individual takes into concern before deciding on a rational action towards another individual. It affects the social situation as one navigates the risks and benefits of an action. By assessing the possible outcomes or alternatives to an action for another individual, the person is making a calculated decision. In another situation such as making a bet, you are calculating the possible lost and how much can be won. If the chances of winning exceeds the cost of losing, the rational decision would be to place the bet. Therefore, the decision to place trust in another individual involves the same rational calculations that are involved in the decision of making a bet.

Even though rational theory is used in Economics and Social settings, there are some similarities and differences. The concept of reward and reinforcement is parallel to each other while the concept of cost is also parallel to the concept of punishment. However, there is a difference of underlying assumptions in both contexts. In social a social setting, the focus is often on the current or past reinforcements instead of the future although there is no guarantee of immediate tangible or intangible returns from another individual. In Economics, decisions are made with heavier emphasis on future rewards.

Despite having both perspectives differ in focus, they primarily reflect on how individuals make different rational decisions when given an immediate or long-term circumstances to consider in their rational decision making.

Criticism

This theory critically helps us to understand the choices an individual or society makes. Even though some decisions are not entirely rational, it is possible that Rational Choice Theory still helps us to understand the motivations behind it. Moreover, there has been a lot of discourse about Rational Choice Theory. It has often been too individualistic, minimalistic and heavily focused on rational decisions in social actions. Sociologists tend to justify any human action as rational as individuals are solely motivated by the pursuit of self-interest. It does not consider the possibility of pure altruism of a social exchange between individuals.

Criticism

Both the assumptions and the behavioral predictions of rational choice theory have sparked criticism from various camps.

The limits of rationality

As mentioned above, some economists have developed models of bounded rationality, such as Herbert Simon, which hope to be more psychologically plausible without completely abandoning the idea that reason underlies decision-making processes. Simon argues factors such as imperfect information, uncertainty and time constraints all affect and limit our rationality, and therefore our decision making skills. Furthermore his concepts of 'satisficing' and 'optimizing' suggest sometimes because of these factors, we settle for a decision which is good enough, rather than the best decision. Other economists have developed more theories of human decision-making that allow for the roles of uncertainty, institutions, and determination of individual tastes by their socioeconomic environment (cf. Fernandez-Huerga, 2008).

Philosophical critiques

Martin Hollis and Edward J. Nell's 1975 book offers both a philosophical critique of neo-classical economics and an innovation in the field of economic methodology. Further, they outlined an alternative vision to neo-classicism based on a rationalist theory of knowledge. Within neo-classicism, the authors addressed consumer behaviour (in the form of indifference curves and simple versions of revealed preference theory) and marginalist producer behaviour in both product and factor markets. Both are based on rational optimizing behaviour. They consider imperfect as well as perfect markets since neo-classical thinking embraces many market varieties and disposes of a whole system for their classification. However, the authors believe that the issues arising from basic maximizing models have extensive implications for econometric methodology (Hollis and Nell, 1975, p. 2). In particular it is this class of models – rational behavior as maximizing behaviour – which provide support for specification and identification. And this, they argue, is where the flaw is to be found. Hollis and Nell (1975) argued that positivism (broadly conceived) has provided neo-classicism with important support, which they then show to be unfounded. They base their critique of neo-classicism not only on their critique of positivism but also on the alternative they propose, rationalism. Indeed, they argue that rationality is central to neo-classical economics – as rational choice – and that this conception of rationality is misused. Demands are made of it that it cannot fulfill. Ultimately, individuals do not always act rationally or conduct themselves in a utility maximising manner.

Duncan K. Foley (2003, p. 1) has also provided an important criticism of the concept of rationality and its role in economics. He argued that

“Rationality” has played a central role in shaping and establishing the hegemony of contemporary mainstream economics. As the specific claims of robust neoclassicism fade into the history of economic thought, an orientation toward situating explanations of economic phenomena in relation to rationality has increasingly become the touchstone by which mainstream economists identify themselves and recognize each other. This is not so much a question of adherence to any particular conception of rationality, but of taking rationality of individual behavior as the unquestioned starting point of economic analysis.

Foley (2003, p. 9) went on to argue that

The concept of rationality, to use Hegelian language, represents the relations of modern capitalist society one-sidedly. The burden of rational-actor theory is the assertion that ‘naturally’ constituted individuals facing existential conflicts over scarce resources would rationally impose on themselves the institutional structures of modern capitalist society, or something approximating them. But this way of looking at matters systematically neglects the ways in which modern capitalist society and its social relations in fact constitute the ‘rational’, calculating individual. The well-known limitations of rational-actor theory, its static quality, its logical antinomies, its vulnerability to arguments of infinite regress, its failure to develop a progressive concrete research program, can all be traced to this starting-point.

More recently Edward J. Nell and Karim Errouaki (2011, Ch. 1) argued that:

The DNA of neoclassical economics is defective. Neither the induction problem nor the problems of methodological individualism can be solved within the framework of neoclassical assumptions. The neoclassical approach is to call on rational economic man to solve both. Economic relationships that reflect rational choice should be ‘projectible’. But that attributes a deductive power to ‘rational’ that it cannot have consistently with positivist (or even pragmatist) assumptions (which require deductions to be simply analytic). To make rational calculations projectible, the agents may be assumed to have idealized abilities, especially foresight; but then the induction problem is out of reach because the agents of the world do not resemble those of the model. The agents of the model can be abstract, but they cannot be endowed with powers actual agents could not have. This also undermines methodological individualism; if behaviour cannot be reliably predicted on the basis of the ‘rational choices of agents’, a social order cannot reliably follow from the choices of agents.

Empirical critiques

In their 1994 work, Pathologies of Rational Choice Theory, Donald P. Green and Ian Shapiro argue that the empirical outputs of rational choice theory have been limited. They contend that much of the applicable literature, at least in political science, was done with weak statistical methods and that when corrected many of the empirical outcomes no longer hold. When taken in this perspective, rational choice theory has provided very little to the overall understanding of political interaction - and is an amount certainly disproportionately weak relative to its appearance in the literature. Yet, they concede that cutting-edge research, by scholars well-versed in the general scholarship of their fields (such as work on the U.S. Congress by Keith Krehbiel, Gary Cox, and Mat McCubbins) has generated valuable scientific progress.

Methodological critiques

Schram and Caterino (2006) contains a fundamental methodological criticism of rational choice theory for promoting the view that the natural science model is the only appropriate methodology in social science and that political science should follow this model, with its emphasis on quantification and mathematization. Schram and Caterino argue instead for methodological pluralism. The same argument is made by William E. Connolly, who in his work Neuropolitics shows that advances in neuroscience further illuminate some of the problematic practices of rational choice theory.

Sociological critiques

Pierre Bourdieu fiercely opposed rational choice theory as grounded in a misunderstanding of how social agents operate. Bourdieu argued that social agents do not continuously calculate according to explicit rational and economic criteria. According to Bourdieu, social agents operate according to an implicit practical logic—a practical sense—and bodily dispositions. Social agents act according to their "feel for the game" (the "feel" being, roughly, habitus, and the "game" being the field).

Other social scientists, inspired in part by Bourdieu's thinking have expressed concern about the inappropriate use of economic metaphors in other contexts, suggesting that this may have political implications. The argument they make is that by treating everything as a kind of "economy" they make a particular vision of the way an economy works seem more natural. Thus, they suggest, rational choice is as much ideological as it is scientific, which does not in and of itself negate its scientific utility.

Critiques on the basis of evolutionary psychology

An evolutionary psychology perspective suggests that many of the seeming contradictions and biases regarding rational choice can be explained as being rational in the context of maximizing biological fitness in the ancestral environment but not necessarily in the current one. Thus, when living at subsistence level where a reduction of resources may have meant death it may have been rational to place a greater value on losses than on gains. Proponents argue it may also explain differences between groups.

Critiques on the basis of emotion research

Proponents of emotional choice theory criticize the rational choice paradigm by drawing on new findings from emotion research in psychology and neuroscience. They point out that rational choice theory is generally based on the assumption that decision-making is a conscious and reflective process based on thoughts and beliefs. It presumes that people decide on the basis of calculation and deliberation. However, cumulative research in neuroscience suggests that only a small part of the brain's activities operate at the level of conscious reflection. The vast majority of its activities consist of unconscious appraisals and emotions. The significance of emotions in decision-making has generally been ignored by rational choice theory, according to these critics. Moreover, emotional choice theorists contend that the rational choice paradigm has difficulty incorporating emotions into its models, because it cannot account for the social nature of emotions. Even though emotions are felt by individuals, psychologists and sociologists have shown that emotions cannot be isolated from the social environment in which they arise. Emotions are inextricably intertwined with people's social norms and identities, which are typically outside the scope of standard rational choice models. Emotional choice theory seeks to capture not only the social but also the physiological and dynamic character of emotions. It represents a unitary action model to organize, explain, and predict the ways in which emotions shape decision-making.

The difference between public and private spheres

Herbert Gintis has also provided an important criticism to rational choice theory. He argued that rationality differs between the public and private spheres. The public sphere being what you do in collective action and the private sphere being what you do in your private life. Gintis argues that this is because “models of rational choice in the private sphere treat agents’ choices as instrumental”. “Behaviour in the public sphere, by contrast, is largely non-instrumental because it is non-consequential". Individuals make no difference to the outcome, “much as single molecules make no difference to the properties of the gas" (Herbert,G). This is a weakness of rational choice theory as it shows that in situations such as voting in an election, the rational decision for the individual would be to not vote as their vote makes no difference to the outcome of the election. However, if everyone were to act in this way the democratic society would collapse as no one would vote. Therefore, we can see that rational choice theory does not describe how everything in the economic and political world works, and that there are other factors that of human behaviour at play.

Neoclassical economics

Neoclassical economics is an approach to economics in which the production, consumption and valuation (pricing) of goods and services are driven by the supply and demand model. According to this line of thought, the value of a good or service is determined through a hypothetical maximization of utility by income-constrained individuals and of profits by firms facing production costs and employing available information and factors of production. This approach has often been justified by appealing to rational choice theory, a theory that has come under considerable question in recent years.

Neoclassical economics dominated microeconomics and, together with Keynesian economics, formed the neoclassical synthesis which dominated mainstream economics as neo-Keynesian economics from the 1950s to the 1970s.[4] It competed with new Keynesian economics as new classical macroeconomics in explaining macroeconomic phenomena from the 1970s until the 1990s, when it was identified as having become a part of the new neoclassical synthesis along with new Keynesianism. There have been many critiques of neoclassical economics, a number of which have been incorporated into newer versions of neoclassical theory, whilst some remain distinct fields.

Classification

The term was originally introduced by Thorstein Veblen in his 1900 article "Preconceptions of Economic Science", in which he related marginalists in the tradition of Alfred Marshall et al. to those in the Austrian School.

No attempt will here be made even to pass a verdict on the relative claims of the recognized two or three main "schools" of theory, beyond the somewhat obvious finding that, for the purpose in hand, the so-called Austrian school is scarcely distinguishable from the neo-classical, unless it be in the different distribution of emphasis. The divergence between the modernized classical views, on the one hand, and the historical and Marxist schools, on the other hand, is wider, so much so, indeed, as to bar out a consideration of the postulates of the latter under the same head of inquiry with the former.

It was later used by John Hicks, George Stigler, and others to include the work of Carl Menger, William Stanley Jevons, Léon Walras, John Bates Clark, and many others. Today it is usually used to refer to mainstream economics, although it has also been used as an umbrella term encompassing a number of other schools of thought, notably excluding institutional economics, various historical schools of economics, and Marxian economics, in addition to various other heterodox approaches to economics.

Neoclassical economics is characterized by several assumptions common to many schools of economic thought. There is not a complete agreement on what is meant by neoclassical economics, and the result is a wide range of neoclassical approaches to various problem areas and domains—ranging from neoclassical theories of labor to neoclassical theories of demographic changes.

Theory

Assumptions and objectives

It was expressed by E. Roy Weintraub that neoclassical economics rests on three assumptions, although certain branches of neoclassical theory may have different approaches:

  1. People have rational preferences between outcomes that can be identified and associated with values.
  2. Individuals maximize utility and firms maximize profits.
  3. People act independently on the basis of full and relevant information.

From these three assumptions, neoclassical economists have built a structure to understand the allocation of scarce resources among alternative ends—in fact, understanding such allocation is often considered the definition of economics to neoclassical theorists. Here's how William Stanley Jevons presented "the problem of Economics".

Given, a certain population, with various needs and powers of production, in possession of certain lands and other sources of material: required, the mode of employing their labor which will maximize the utility of their produce.

From the basic assumptions of neoclassical economics comes a wide range of theories about various areas of economic activity. For example, profit maximization lies behind the neoclassical theory of the firm, while the derivation of demand curves leads to an understanding of consumer goods, and the supply curve allows an analysis of the factors of production. Utility maximization is the source for the neoclassical theory of consumption, the derivation of demand curves for consumer goods, and the derivation of labor supply curves and reservation demand.

Supply and demand model

Market analysis is typically the neoclassical answer to price questions, such as why does an apple cost less than an automobile, why does the performance of work command a wage, or how to account for interest as a reward for saving. An important device of neoclassical market analysis is the graph presenting supply and demand curves. The curves are reflecting the behavior of individual buyers and individual sellers. Buyers and sellers interact with each other in and through these markets, and their interactions determine the market prices of anything they buy and sell. In the following graph, the specific price of the commodity being bought/sold is represented by P*.

Supply-demand-equilibrium

In reaching agreed outcomes of their interactions, the market behaviors of buyers and sellers are driven by their preferences (= wants, utilities, tastes, choices) and productive abilities (= technologies, resources). This creates a complex relationship between buyers and sellers. Thus, the geometrical analytics of supply and demand is only a simplified way how to describe and explore their interaction. Market supply and demand are aggregated across firms and individuals. Their interactions determine equilibrium output and price. The market supply and demand for each factor of production is derived analogously to those for market final output to determine equilibrium income and the income distribution. Factor demand incorporates the marginal-productivity relationship of that factor in the output market.

Neoclassical economics emphasizes equilibria, which are the solutions of agent maximization problems. Regularities in economies are explained by methodological individualism, the position that economic phenomena can be explained by aggregating over the behavior of agents. The emphasis is on microeconomics. Institutions, which might be considered as prior to and conditioning individual behavior, are de-emphasized. Economic subjectivism accompanies these emphases. See also general equilibrium.

Utility theory of value

Neoclassical economics uses the utility theory of value, which states that the value of a good is determined by the marginal utility experienced by the user. This is one of the main distinguishing factors between neoclassical economics and other earlier economic theories, such as Classical and Marxian, which use the labor theory of value that value is determined by the labor required for production.

The partial definition of the neoclassical theory of value states that the value of an object of market exchange is determined by human interaction between the preferences and productive abilities of individuals. This is one of the most important neoclassical hypotheses. However, the neoclassical theory also asks what exactly is causing the supply and demand behaviors of buyers and sellers, and how exactly the preferences and productive abilities of people determine the market prices. Therefore, the neoclassical theory of value is a theory of these forces: the preferences and productive abilities of humans. They are the final causal determinants of the behavior of supply and demand and therefore of value. According to neoclassical economics, individual preferences and productive abilities are the essential forces that generate all other economic events (demands, supplies, and prices).

Cambridge quantity theory of money

The Cambridge version of the quantity theory of money was developed mainly by Alfred Marshall, Arthur Cecil Pigou, Ralph George Hawtrey and Dennis Holme Robertson, and is understood as the income version of the money theory. The basis of the Cambridge quantity theory of money is the Cambridge equation:

where is the demand for money, is the Cambridge (Marshall) coefficient expressing the part of real income in the form of cash, is the price level and is the real income. The left side of the Cambridge equation is expressing the money supply, i.e. the amount of money that people have at their disposal, whereas the right side is expressing the sum of cash people actually want to have, i.e. it is expressing the money demand. Thus, the Cambridge equation is focusing on exploring the conditions of equilibrium in the money market.

Market failure and externalities

Despite favoring markets to organize economic activity, neoclassical theory acknowledges that markets do not always produce the socially desirable outcome due to the presence of externalities. Externalities are considered a form of market failure. Neoclassical economists vary in terms of the significance they ascribe to externalities in market outcomes.

Pareto criterion

In a market with a very large number of participants and under appropriate conditions, for each good, there will be a unique price that allows all welfare–improving transactions to take place. This price is determined by the actions of the individuals pursuing their preferences. If these prices are flexible, meaning that all parties are able to pursue transactions at any rates they find mutually beneficial, they will, under appropriate assumptions, tend to settle at price levels that allow for all welfare–improving transactions. Under these assumptions, free-market processes yield an optimum of social welfare. This type of group welfare is called the Pareto optimum (criterion) after its discoverer Vilfredo Pareto. Wolff and Resnick (2012) describe the Pareto optimality in another way. According to them, the term "Pareto optimal point" signifies the equality of consumption and production, which indicates that the demand (as a ratio of marginal utilities) and supply (as a ratio of marginal costs) sides of an economy are in balance with each other. The Pareto optimum point also signifies that society has fully realized its potential output.

Normative judgments in neoclassical economics are shaped by the Pareto criterion. As a result, many neoclassical economists favor a relatively laissez-faire approach to government intervention in markets, since it is very difficult to make a change where no one will be worse off. However, many less conservative neoclassical economists instead use the compensation principle, which says that an intervention is good if the total gains are larger than the total losses, even if losers are not compensated in practice.

International trade

Neoclassical economics favors free trade according to David Ricardo's theory of comparative advantage. This idea holds that free trade between two countries is always mutually beneficial because it allows the greatest total consumption in both countries.

Origins

Classical economics, developed in the 18th and 19th centuries, included a value theory and distribution theory. The value of a product was thought to depend on the costs involved in producing that product. The explanation of costs in classical economics was simultaneously an explanation of distribution. A landlord received rent, workers received wages, and a capitalist tenant farmer received profits on their investment. This classic approach included the work of Adam Smith and David Ricardo.

However, some economists gradually began emphasizing the perceived value of a good to the consumer. They proposed a theory that the value of a product was to be explained with differences in utility (usefulness) to the consumer. (In England, economists tended to conceptualize utility in keeping with the utilitarianism of Jeremy Bentham and later of John Stuart Mill.)

The third step from political economy to economics was the introduction of marginalism and the proposition that economic actors made decisions based on margins. For example, a person decides to buy a second sandwich based on how full he or she is after the first one, a firm hires a new employee based on the expected increase in profits the employee will bring. This differs from the aggregate decision-making of classical political economy in that it explains how vital goods such as water can be cheap, while luxuries can be expensive.

Marginal revolution

The change in economic theory from classical to neoclassical economics has been called the "marginal revolution", although it has been argued that the process was slower than the term suggests. It is frequently dated from William Stanley Jevons's Theory of Political Economy (1871), Carl Menger's Principles of Economics (1871), and Léon Walras's Elements of Pure Economics (1874–1877). Historians of economics and economists have debated:

  • Whether utility or marginalism was more essential to this revolution (whether the noun or the adjective in the phrase "marginal utility" is more important)
  • Whether there was a revolutionary change of thought or merely a gradual development and change of emphasis from their predecessors
  • Whether grouping these economists together disguises differences more important than their similarities.

In particular, Jevons saw his economics as an application and development of Jeremy Bentham's utilitarianism and never had a fully developed general equilibrium theory. Menger did not embrace this hedonic conception, explained diminishing marginal utility in terms of subjective prioritization of possible uses, and emphasized disequilibrium and the discrete; further, Menger had an objection to the use of mathematics in economics, while the other two modeled their theories after 19th-century mechanics. Jevons built on the hedonic conception of Bentham or of Mill, while Walras was more interested in the interaction of markets than in explaining the individual psyche.

Alfred Marshall's textbook, Principles of Economics (1890), was the dominant textbook in England a generation later. Marshall's influence extended elsewhere; Italians would compliment Maffeo Pantaleoni by calling him the "Marshall of Italy". Marshall thought classical economics attempted to explain prices by the cost of production. He asserted that earlier marginalists went too far in correcting this imbalance by overemphasizing utility and demand. Marshall thought that "We might as reasonably dispute whether it is the upper or the under blade of a pair of scissors that cuts a piece of paper, as to whether the value is governed by utility or cost of production".

Marshall explained price by the intersection of supply and demand curves. The introduction of different market "periods" was an important innovation of Marshall's:

  • Market period. The goods produced for sale on the market are taken as given data, e.g. in a fish market. Prices quickly adjust to clear markets.
  • Short period. Industrial capacity is taken as given. The level of output, the level of employment, the inputs of raw materials, and prices fluctuate to equate marginal cost and marginal revenue, where profits are maximized. Economic rents exist in short period equilibrium for fixed factors, and the rate of profit is not equated across sectors.
  • Long period. The stock of capital goods, such as factories and machines, is not taken as given. Profit-maximizing equilibria determine both industrial capacity and the level at which it is operated.
  • Very long period. Technology, population trends, habits, and customs are not taken as given but allowed to vary in very long period models.

Marshall took supply and demand as stable functions and extended supply and demand explanations of prices to all runs. He argued supply was easier to vary in longer runs, and thus became a more important determinant of price in the very long run.

Cambridge and Lausanne school

Cambridge and Lausanne School of economics form the basis of neoclassical economics. Until the 1930s, the evolution of neoclassical economics was determined by the Cambridge school and was based on the marginal equilibrium theory. At the beginning of the 1930s, the Lausanne general equilibrium theory became the general basis of neoclassical economics and the marginal equilibrium theory was understood as its simplification.

The thinking of the Cambridge school continued in the steps of classical political economics and its traditions but was based on the new approach that originated from the marginalist revolution. Its founder was Alfred Marshall, and among the main representatives were Arthur Cecil Pigou, Ralph George Hawtrey and Dennis Holme Robertson. Pigou worked on the theory of welfare economics and the quantity theory of money. Hawtrey and Robertson developed the Cambridge cash balance approach to theory of money and influenced the trade cycle theory. Until the 1930s, John Maynard Keynes was also influencing the theoretical concepts of the Cambridge school. The key characteristic of the Cambridge school was its instrumental approach to the economy – the role of the theoretical economist is first to define theoretical instruments of economic analysis and only just then apply them to real economic problems.

The main representatives of the Lausanne school of economic thought were Léon Walras, Vilfredo Pareto and Enrico Barone. The school became famous for developing the general equilibrium theory. In the contemporary economy, the general equilibrium theory is the methodologic basis of mainstream economics in the form of New classical macroeconomics and New Keynesian macroeconomics.

Evolution

The evolution of neoclassical economics can be divided into three phases. The first phase (= a pre-Keynesian phase) is dated between the initial forming of neoclassical economics (the second half of the nineteenth century) and the arrival of Keynesian economics in the 1930s. The second phase is dated between the year 1940 and the half of the 1970s. During this era, Keynesian economics was dominating the world's economy but neoclassical economics did not cease to exist. It continued in the development of its microeconomics theory and began creating its own macroeconomics theory. The development of the neoclassical macroeconomic theory was based on the development of the quantity theory of money and the theory of distribution. One of the products of the second phase was the Neoclassical synthesis, representing a special combination of neoclassical microeconomics and Keynesian macroeconomics. The third phase began in the 1970s and is labeled as the neoclassical renaissance, the revival of neoclassical economics. During this era, Neo-Keynesian economics was in crisis, which encouraged the creation of new neoclassical lines of thoughts such as Monetarism, New classical macroeconomics, Supply-side economics, or the Public choice theory. Despite the diverse focus and approach of these theories, they are all based on the theoretic and methodologic principles of traditional neoclassical economics.

An important change in neoclassical economics occurred around 1933. Joan Robinson and Edward H. Chamberlin, with the nearly simultaneous publication of their respective books, The Economics of Imperfect Competition (1933) and The Theory of Monopolistic Competition (1933), introduced models of imperfect competition. Theories of market forms and industrial organization grew out of this work. They also emphasized certain tools, such as the marginal revenue curve. In her book, Robinson formalized a type of limited competition. The conclusions of her work for welfare economics were worrying: they were implying that the market mechanism operates in a way that the workers are not paid according to the full value of their marginal productivity of labor and that also the principle of consumer sovereignty is impaired. This theory heavily influenced the anti–trust policies of many Western countries in the 1940s and 1950s.

Joan Robinson's work on imperfect competition, at least, was a response to certain problems of Marshallian partial equilibrium theory highlighted by Piero Sraffa. Anglo-American economists also responded to these problems by turning towards general equilibrium theory, developed on the European continent by Walras and Vilfredo Pareto. J. R. Hicks's Value and Capital (1939) was influential in introducing his English-speaking colleagues to these traditions. He, in turn, was influenced by the Austrian School economist Friedrich Hayek's move to the London School of Economics, where Hicks then studied.

These developments were accompanied by the introduction of new tools, such as indifference curves and the theory of ordinal utility. The level of mathematical sophistication of neoclassical economics increased. Paul Samuelson's Foundations of Economic Analysis (1947) contributed to this increase in mathematical modeling.

The interwar period in American economics has been argued to have been pluralistic, with neoclassical economics and institutionalism competing for allegiance. Frank Knight, an early Chicago school economist attempted to combine both schools. But this increase in mathematics was accompanied by greater dominance of neoclassical economics in Anglo-American universities after World War II. Some argue that outside political interventions, such as McCarthyism, and internal ideological bullying played an important role in this rise to dominance.

Hicks' book, Value and Capital had two main parts. The second, which was arguably not immediately influential, presented a model of temporary equilibrium. Hicks was influenced directly by Hayek's notion of intertemporal coordination and paralleled by earlier work by Lindhal. This was part of an abandonment of disaggregated long-run models. This trend probably reached its culmination with the Arrow–Debreu model of intertemporal equilibrium. The Arrow–Debreu model has canonical presentations in Gérard Debreu's Theory of Value (1959) and in Arrow and Hahn's "General Competitive Analysis" (1971).

Neoclassical synthesis

Many of these developments were against the backdrop of improvements in both econometrics, that is the ability to measure prices and changes in goods and services, as well as their aggregate quantities, and in the creation of macroeconomics, or the study of whole economies. The attempt to combine neo-classical microeconomics and Keynesian macroeconomics would lead to the neoclassical synthesis which was the dominant paradigm of economic reasoning in English-speaking countries from the 1950s till the 1970s. Hicks and Samuelson were for example instrumental in mainstreaming Keynesian economics.

The dominance of Neo-Keynesian economics was upset by its inability to explain the economic crises of the 1970s- neoclassical economics emerged distinctly in macroeconomics as the new classical school, which sought to explain macroeconomic phenomenon using neoclassical microeconomics. It and its contemporary New Keynesian economics contributed to the new neoclassical synthesis of the 1990s, which informs much of mainstream macroeconomics today.

Cambridge capital controversy

Problems exist with making the neoclassical general equilibrium theory compatible with an economy that develops over time and includes capital goods. This was explored in a major debate in the 1960s—the "Cambridge capital controversy"—about the validity of neoclassical economics, with an emphasis on economic growth, capital, aggregate theory, and the marginal productivity theory of distribution. There were also internal attempts by neoclassical economists to extend the Arrow–Debreu model to disequilibrium investigations of stability and uniqueness. However, a result known as the Sonnenschein–Mantel–Debreu theorem suggests that the assumptions that must be made to ensure that equilibrium is stable and unique are quite restrictive.

Criticisms

Although the neoclassical approach is dominant in economics, the field of economics includes others, such as Marxist, Behavioral, Schumpeterian, Developmentalist, Austrian, Post Keynesian, and Institutionalist schools. All of these schools differ with the neoclassical school and each other, and incorporate various criticisms of the neoclassical economics. Not all criticism comes from other schools: some prominent economists such as Nobel Prize recipient and former chief economist of the World Bank Joseph Stiglitz are vocally critical of mainstream neoclassical economics.

Methodology and mathematical models

Some see mathematical models used in contemporary research in mainstream economics as having transcended neoclassical economics, while others disagree. Mathematical models also include those in game theory, linear programming, and econometrics. Critics of neoclassical economics are divided into those who think that highly mathematical method is inherently wrong and those who think that mathematical method is useful even if neoclassical economics has other problems.

Critics such as Tony Lawson contend that neoclassical economics' reliance on functional relations is inadequate for social phenomena in which knowledge of one variable does not reliably predict another. The different factors affecting economic outcomes cannot be experimentally isolated from one another in a laboratory; therefore the explanatory and predictive power of mathematical economic analysis is limited. Lawson proposes an alternative approach called the contrast explanation which he says is better suited for determining causes of events in social sciences. More broadly, critics of economics as a science vary, with some believing that all mathematical economics is problematic or even pseudoscience and others believing it is still useful but has less certainty and higher risk of methodology problems than in hard sciences.

Milton Friedman, one of the most prominent and influential neoclassical economists of the 20th century, responded to criticisms that assumptions in economic models were often unrealistic by saying that theories should be judged by their ability to predict events rather than by the supposed realism of their assumptions. He claimed that, on the contrary, a theory with more absurd assumptions has stronger predictive power. He argued that a theory's ability to theoretically explain reality is irrelevant compared to its ability to empirically predict reality, no matter the method of getting to that prediction.

Objectivity and pluralism

Neoclassical economics is often criticized for having a normative bias despite sometimes claiming to be "value-free". Such critics argue an ideological side of neoclassical economics, generally to argue that students should be taught more than one economic theory and that economics departments should be more pluralistic.

Rational behavior assumptions

One of the most widely criticized aspects of neoclassical economics is its set of assumptions about human behavior and rationality. According to Edward Fullbrook, these assumptions were chosen not because they were observed to be true by studying human behavior, but because they were the required conditions to reach a market equilibrium. The "economic man", or a hypothetical human who acts according to neoclassical assumptions, does not necessarily behave the same way as humans do in reality. The economist and critic of capitalism Thorstein Veblen claimed that neoclassical economics assumes a person to be:

[A] lightning calculator of pleasures and pains, who oscillates like a homogeneous globule of desire of happiness under the impulse of stimuli that shift about the area, but leave him intact.

His characterization references a number of commonly criticized rationality assumptions: that people make decisions using a rigid utilitarian framework, have perfect information available about their options, have perfect information processing ability allowing them to immediately calculate utility for all possible options, and are independent decision-makers whose choices are unaffected by their surroundings or by other people.

While Veblen is from the Institutional school, the Behavioral school of economics is focused on studying the mechanisms of human decision-making and how they differ from neoclassical assumptions of rationality. Altruistic or empathy-based behavior is another form of "non-rational" decision making studied by behavioral economists, which differs from the neoclassical assumption that people only act in self-interest. Behavioral economists account for how psychological, neurological, and even emotional factors significantly affect economic perceptions and behaviors.

Rational choice theory need not be problematic according to a paper written by the economist Gary Becker which was published in 1962 in the Journal of Political Economy called "Irrational Behavior and Economic Theory." According to Becker, this paper demonstrates "how the important theorems of modern economics result from a general principle which not only includes rational behavior and survivor arguments as special cases, but also much irrational behavior." The specific important theorems and results which are shown to result from a broad range of different type of irrational behavior as well as rational behavior by market participants in the paper are that market demand curves are downward sloping or "negatively inclined", and that if an industry transformed from a competitive industry to a completely monopolistic cartel and profits are always maximized, then output per firm under the cartel would decrease compared to its equilibrium level when the industry was competitive.

This paper was largely based on the 1950 paper "Uncertainty, Evolution, and Economic Theory" by Armen Alchian. The paper sets out a justification for supply analysis separate from relying on the assumption of rational consumption, the representative firm and the way neoclassical economists analyze firm behavior in markets which does not apply on rational behavior by the decision makers in those firms, nor any other type of foresighted or goal directed behavior by them. Becker's subsequent 1962 paper provides an independent justification for neoclassical market demand analysis. The two papers offer separate justifications for the use of neoclassical methodology for supply and demand analysis without relying on implausible assumptions.

Methodological individualism

Neoclassical economics offers an approach to study the economic behavior of homo-economicus. This theory is based on methodological individualism and adopts an atomistic approach to social phenomena, according to which social atoms are the individuals and their actions. According to this doctrine, individuals are independent of social phenomena, but the opposite is not true. Individuals' actions can explain macro-scale behavior, and social collections are nothing more than aggregates, and they do not add anything to its components (Ibid). Although methodological individualism does not negate complex social phenomena such as institutions or behavioral rules, it argues any explanation should be based on constituent components' characteristics of those institutions. This is a reductionist approach based on which it is believed that the characteristics of the social system are derived from the individuals' preferences and their actions.

A critique of this approach is that the individuals' preferences and interests are not fixed. The structures contextualize individual's. According to social constructivists, systems are co-constituted alongside the actors, and ideas within the system define actors' identities, their interests, and thus their behavior. In this regard, actors in various circumstances (exposed to different impressions and experiences) will construct their interests and preferences differently, both within each other and over time. Given the individualistic foundation of the economic theory, critics argue that this theory should consider individual action's structural contexts.

Inequality

Neoclassical economics is often criticized as promoting policies that increase inequality and as failing to recognise the impact of inequality on economic outcomes. In the case of the former claim, neoclassical economics is often used for analysis in support of policies reducing economic inequality—in particular through determining the diminishing marginal utility of income, whereby poorer individuals gain greater net benefits from a given increase in income than comparable richer individuals, but more generally by being the primary means by which the impact on inequality of any given policy is assessed. In the case of the latter claim, neoclassical economics is the prevailing lens through which the relationship between inequality and economic outcomes is studied.

Ethics of markets

Neoclassical economics tends to promote commodification and privatization of goods due to its principle that market exchange generally results in the most effective allocation of goods. For example, some economists support markets for human organs, on the basis that it increases supply of life-saving organs and benefits willing donors financially. However, there are arguments in moral philosophy that use of markets for certain goods is inherently unethical. Political philosopher Michael Sandel summarizes that market exchanges have two ethical problems: coercion and corruption. Coercion happens because market participation may not be as free as proponents often claim: people often participate in markets because it is the only way to survive, which is not truly voluntary. Corruption describes how commodification of a good can inherently degrade its value.

Bounded rationality

From Wikipedia, the free encyclopedia

Bounded rationality is the idea that rationality is limited when individuals make decisions. In other words, humans' "preferences are determined by changes in outcomes relative to a certain reference level". Limitations include the difficulty of the problem requiring a decision, the cognitive capability of the mind, and the time available to make the decision. Decision-makers, in this view, act as satisficers, seeking a satisfactory solution, rather than an optimal solution. Therefore, humans do not undertake a full cost-benefit analysis to determine the optimal decision, but rather, choose an option that fulfils their adequacy criteria.

Some models of human behavior in the social sciences assume that humans can be reasonably approximated or described as "rational" entities, as in rational choice theory or Downs' political agency model. The concept of bounded rationality complements "rationality as optimization", which views decision-making as a fully rational process of finding an optimal choice given the information available. Therefore, bounded rationality can be said to address the discrepancy between the assumed perfect rationality of human behaviour (which is utilised by other economics theories such as the Neoclassical approach), and the reality of human cognition. In short, bounded rationality revises notions of "perfect" rationality to account for the fact that perfectly rational decisions are often not feasible in practice because of the intractability of natural decision problems and the finite computational resources available for making them. The concept of bounded rationality continues to influence (and be debated in) different disciplines, including economics, psychology, law, political science, and cognitive science.

Background and Motivation

Bounded rationality was coined by Herbert A. Simon, where it was proposed as an alternative basis for the mathematical and neoclassical economic modelling of decision-making, as used in economics, political science, and related disciplines. Many economics models assume that agents are on average rational, and can in large quantities be approximated to act according to their preferences in order to maximise utility. With bounded rationality, Simon's goal was "to replace the global rationality of economic man with a kind of rational behavior that is compatible with the access to information and the computational capacities that are actually possessed by organisms, including man, in the kinds of environments in which such organisms exist."

In Models of Man, Simon argues that most people are only partly rational, and are irrational in the remaining part of their actions. In another work, he states "boundedly rational agents experience limits in formulating and solving complex problems and in processing (receiving, storing, retrieving, transmitting) information". Simon used the analogy of a pair of scissors, where one blade represents "cognitive limitations" of actual humans and the other the "structures of the environment", illustrating how minds compensate for limited resources by exploiting known structural regularity in the environment.

Simon describes a number of dimensions along which "classical" models of rationality can be made somewhat more realistic, while remaining within the vein of fairly rigorous formalization. These include:

  • limiting the types of utility functions
  • recognizing the costs of gathering and processing information
  • the possibility of having a "vector" or "multi-valued" utility function

Simon suggests that economic agents use heuristics to make decisions rather than a strict rigid rule of optimization. They do this because of the complexity of the situation. An example of behaviour inhibited by heuristics can be seen when comparing the cognitive strategies utilised in simple situations (e.g Tic-tac-toe), in comparison to strategies utilised in difficult situations (e.g Chess). Both games, as defined by game theory economics, are finite games with perfect information, and therefore equivalent. However, within Chess, mental capacities and abilities are a binding constraint, therefore optimal choices are not a possibility. Thus, in order to test the mental limits of agents, complex problems, such as those within Chess, should be studied to test how individuals work around their cognitive limits, and what behaviours or heuristics are used to form solutions

Model extensions

As decision-makers have to make decisions about how and when to decide, Ariel Rubinstein proposed to model bounded rationality by explicitly specifying decision-making procedures. This puts the study of decision procedures on the research agenda.

Gerd Gigerenzer opines that decision theorists, to some extent, have not adhered to Simon's original ideas. Rather, they have considered how decisions may be crippled by limitations to rationality, or have modeled how people might cope with their inability to optimize. Gigerenzer proposes and shows that simple heuristics often lead to better decisions than theoretically optimal procedures. Moreover, Gigerenzer states, agents react relative to their environment and use their cognitive processes to adapt accordingly.

Huw Dixon later argues that it may not be necessary to analyze in detail the process of reasoning underlying bounded rationality. If we believe that agents will choose an action that gets them "close" to the optimum, then we can use the notion of epsilon-optimization, which means we choose our actions so that the payoff is within epsilon of the optimum. If we define the optimum (best possible) payoff as , then the set of epsilon-optimizing options S(ε) can be defined as all those options s such that:

.

The notion of strict rationality is then a special case (ε=0). The advantage of this approach is that it avoids having to specify in detail the process of reasoning, but rather simply assumes that whatever the process is, it is good enough to get near to the optimum.

From a computational point of view, decision procedures can be encoded in algorithms and heuristics. Edward Tsang argues that the effective rationality of an agent is determined by its computational intelligence. Everything else being equal, an agent that has better algorithms and heuristics could make "more rational" (closer to optimal) decisions than one that has poorer heuristics and algorithms. Tshilidzi Marwala and Evan Hurwitz in their study on bounded rationality observed that advances in technology (e.g. computer processing power because of Moore's law, artificial intelligence, and big data analytics) expand the bounds that define the feasible rationality space. Because of this expansion of the bounds of rationality, machine automated decision making makes markets more efficient.

It is also important to consider that the model of bounded rationality also extends to bounded self-interest, in which humans are sometimes willing to forsake their own self-interests for the benefits of others, something that has not been considered in earlier economic models.

Behavioral Economics

Bounded rationality implies the idea that humans take reasoning shortcuts that may lead to sub-optimal decision-making. Behavioural economists engage in mapping the decision shortcuts that agents use in order to help increase the effectiveness of human decision-making. One treatment of this idea comes from Cass Sunstein and Richard Thaler's Nudge. Sunstein and Thaler recommend that choice architectures are modified in light of human agents' bounded rationality. A widely cited proposal from Sunstein and Thaler urges that healthier food be placed at sight level in order to increase the likelihood that a person will opt for that choice instead of a less healthy option. Some critics of Nudge have argued that modifying choice architectures will lead to people becoming worse decision-makers.

Furthermore, bounded rationality attempts to address assumption points discussed within Neoclassical Economics theory during the 1950s. This theory assumes that the complex problem, the way in which the problem is presented, all alternative choices, and a utility function, are all provided to decision-makers in advance, where this may not be realistic. This was widely used and accepted for a number of decades, however economists realised some disadvantages exist in utilising this theory. This theory did not consider how problems are initially discovered by decision-makers, which could have an impact on the overall decision. Additionally, personal values, the way in which alternatives are discovered and created, and the environment surrounding the decision-making process are also not considered when using this theory. Alternatively, bounded rationality focuses on the cognitive ability of the decision-maker and the factors which may inhibit optimal decision-makingAdditionally, placing a focus on organisations rather than focusing on markets as Neoclassical Economics theory does, bounded rationality is also the basis for many other economics theories (e.g. Organisational theory) as it emphasises that the "...performance and success of an organisation is governed primarily by the psychological limitations of its members..." as stated by John D.W. Morecroft (1981).

In Psychology

The collaborative works of Daniel Kahneman and Amos Tversky expand upon Herbert A. Simon's ideas in the attempt to create a map of bounded rationality. The research attempted to explore the choices made by what was assumed as rational agents compared to the choices made by individuals optimal beliefs and their satisficing behaviour. Kahneman cites that the research contributes mainly to the school of psychology due to imprecision of psychological research to fit the formal economic models, however, the theories are useful to economic theory as a way to expand simple and precise models and cover diverse psychological phenomena. Three major topics covered by the works of Daniel Kahneman and Amos Tversky include Heuristics of judgement, risky choice, and framing effect, which were a culmination of research that fit under what was defined by Herbert A. Simon as the Psychology of Bounded Rationality. In contrast to the work of Simon; Kahneman and Tversky aimed to focus on the effects bounded rationality had on simple tasks which therefore placed more emphasis on errors in cognitive mechanisms irrespective of the situation.[8]

Influence on social network structure

Recent research has shown that bounded rationality of individuals may influence the topology of the social networks that evolve among them. In particular, Kasthurirathna and Piraveenan have shown that in socio-ecological systems, the drive towards improved rationality on average might be an evolutionary reason for the emergence of scale-free properties. They did this by simulating a number of strategic games on an initially random network with distributed bounded rationality, then re-wiring the network so that the network on average converged towards Nash equilibria, despite the bounded rationality of nodes. They observed that this re-wiring process results in scale-free networks. Since scale-free networks are ubiquitous in social systems, the link between bounded rationality distributions and social structure is an important one in explaining social phenomena.

Conclusion

Bounded rationality challenges the rationality assumptions widely accepted between the 1950s and 1970s which were initially used when considering expected utility maximisation, Bayesian probability judgements, and other market-focused economic calculations. Not only does the concept focus on the ways in which humans subconsciously use satisficing in order to make decisions, but also emphasises that humans infer to a great extent, given the limited information they access prior to decision-making for complex problems. Although this concept realistically delves into decision-making and human cognition, challenging earlier theories which assumed perfect rational cognition and behaviour, bounded rationality can mean something different to everyone, and the way each person satisfices can vary dependant on their environment and the information they have access to.

Political psychology

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