Mental accounting

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An example of mental accounting is people's willingness to pay more for goods when using credit cards than if they are paying with cash. This phenomenon is referred to as payment decoupling. Paying with a Credit Card (28886645201).jpg
An example of mental accounting is people's willingness to pay more for goods when using credit cards than if they are paying with cash. This phenomenon is referred to as payment decoupling.

Mental accounting (or psychological accounting) is a model of consumer behaviour developed by Richard Thaler that attempts to describe the process whereby people code, categorize and evaluate economic outcomes. [2] Mental accounting incorporates the economic concepts of prospect theory and transactional utility theory to evaluate how people create distinctions between their financial resources in the form of mental accounts, which in turn impacts the buyer decision process and reaction to economic outcomes. [3] People are presumed to make mental accounts as a self control strategy to manage and keep track of their spending and resources. [4] People budget money into mental accounts for savings (e.g., saving for a home) or expense categories (e.g., gas money, clothing, utilities). [5] People also are assumed to make mental accounts to facilitate savings for larger purposes (e.g., a home or college tuition). [6] Mental accounting can result in people demonstrating greater loss aversion for certain mental accounts, resulting in cognitive bias that incentivizes systematic departures from consumer rationality. Through increased understanding of mental accounting differences in decision making based on different resources, and different reactions based on similar outcomes can be greater understood.

Contents

As Thaler puts it, “All organizations, from General Motors down to single person households, have explicit and/or implicit accounting systems. The accounting system often influences decisions in unexpected ways”. [7] Particularly, individual expenses will usually not be considered in conjunction with the present value of one’s total wealth; they will be instead considered in the context of two accounts: the current budgetary period (this could be a monthly process due to bills, or yearly due to an annual income), and the category of expense. [8] People can even have multiple mental accounts for the same kind of resource. A person may use different monthly budgets for grocery shopping and eating out at restaurants, for example, and constrain one kind of purchase when its budget has run out while not constraining the other kind of purchase, even though both expenditures draw on the same fungible resource (income). [9]

One detailed application of mental accounting, the Behavioral Life Cycle Hypothesis posits that people mentally frame assets as belonging to either current income, current wealth or future income and this has implications for their behavior as the accounts are largely non-fungible and marginal propensity to consume out of each account is different. [10]

Utility, value and transaction

In mental accounting theory, the framing effect defines that the way a person subjectively frames a transaction in their mind will determine the utility they receive or expect. [11] The concept of framing is adopted in prospect theory, which is commonly used by mental accounting theorists as the value function in their analysis (Richard Thaler Included [12] ). In Prospect Theory, the value function is concave for gains (implying an aversion to risk), indicating decreasing marginal utility with accumulation of gain. The value function is convex for losses (implying a risk-seeking attitude). A concave value function for gain incentivizes risk-averse behavior because marginal gain decreases relative increase in value. Conversely a convex value function for losses means that the impact of a loss is more detrimental to a person than an equivalent gain, thus incentivizing risk-seeking behavior in order to avoid loss. These proponents of the value function portray the concept of loss aversion, which asserts that people are more likely to make decisions in order to minimize loss than to maximise gain. [13]

Given the Prospect Theory framework, how do people interpret, or ‘account for’, multiple transactions/outcomes, of the format ? They can either view the outcomes jointly, and receive , in which case the outcomes are integrated, or , in which case we say that the outcomes are segregated. The choice to integrate or segregate multiple outcomes can be beneficial or detrimental to overall utility depending on correctness of application. [14] Due to the nature of our value function’s different slopes for gains and losses, our utility is maximized in different ways, depending on how we code the four kinds of transactions and (as gains or as losses):

This graph shows how with two outcomes that in aggregate make up a mixed loss, more value is achieved by treating the outcomes separately. This is the "silver lining". Silver Lining.png
This graph shows how with two outcomes that in aggregate make up a mixed loss, more value is achieved by treating the outcomes separately. This is the "silver lining".

1) Multiple gains: and are both considered gains. Here, we see that . Thus, we want to segregate multiple gains.

2) Multiple losses: and are both considered losses. Here, we see that . We want to integrate multiple losses.

3) Mixed gain: one of and is a gain and one is a loss, however the gain is the larger of the two. In this case, . Utility is maximized when we integrate a mixed gain.

4) Mixed loss: again, one of and is a gain and one is a loss, however the loss is now significantly larger than the gain. In this case, . Clearly, we don't want to integrate a mixed loss when the less is significantly larger than the gain. This is often referred to as a "silver lining", a reference to the folk maxim "every cloud has a silver lining". When the loss is just barely larger than the gain, integration may be preferred.

Integration and segregation of outcomes is a means of framing that can impact the overall utility derived from multiple outcomes. Mental accounting interprets the tendency of people to mentally segregate their financial resources into different categories. In the event of financial losses or gains in different mental accounts, people will be impacted differently than if the financial loss was integrated across their entire financial portfolio. In the event of multiple gain and mixed loss, mental accounting will segregate outcomes resulting in maximised utility. In the event of multiple losses and mixed gain, mental accounting will segregate outcomes resulting in minimized utility.

There are two values attached to any transaction - acquisition value and transaction value. Acquisition value is the money that one is ready to part with for physically acquiring some good. [15] Transaction value is the value one attaches to having a good deal. [15] If the price that one is paying is equal to the mental reference price for the good, the transaction value is zero. If the price is lower than the reference price, the transaction utility is positive. Total utility received from a transaction, then, is the sum of acquisition utility and transaction utility.

Pain of Paying

A more proximal psychological mechanism through which mental accounting influences spending is through its influence on the pain of paying that is associated with spending money from a mental account. [16] Pain of paying is a negative affective response associated with a financial loss. Prototypical examples are the unpleasant feeling that one experiences when watching the fare increase on a taximeter or at the gas pump. When considering an expense, consumers appear to compare the cost of the expense to the size of an account that it would deplete (e.g., numerator vs. denominator). [17] A $30 t-shirt, for example, would be a subjectively larger expense when drawn from $50 in one's wallet than $500 in one's checking account. The larger the fraction, the more pain of paying the purchase appears to generate and the less likely consumers are to then exchange money for the good. Other evidence of the relation between pain of paying and spending include the lower debt held by consumers who report experiencing a higher pain of paying for the same goods and services than consumers who report experiencing less pain of paying. [18]

Main principles of mental accounts

Richard Thaler divided the concept mental accounting into two main principles; segregation of gains and losses, and account reference points. [19] Both principles utilize concepts related to utility and pain of paying to interpret how people evaluate economic outcomes.

Segregation of gains and losses

A main principle of mental accounting is the assertion that people frame gains and losses by segregating into different mental accounts rather than integrating into their overall account. The impact of this tendency means that outcomes can be framed based on the context of a decision. In mental accounting the framing of a decision reduces from the overall account to a smaller segregated account which can incentivize purchase decisions. An example of this was posed by Thaler where people were more inclined to drive 20 minutes to save $5 on a $15 purchase than on a $125 purchase. [19] The principle applies to mental accounting where if gains and losses are viewed relative to a smaller segregated account then the outcome is viewed differently.

Account reference points

Account reference points refer to the tendency for people to set a reference point on a current decision based on prior outcome in the same mental account. As a result the impact of prior outcomes integrate into the current decision when determining overall utility. An example was posed by Thaler where gamblers were more inclined to make risk-seeking bets on the last race of the day. [19] This phenomenon was justified by the assertion that gamblers segregate the gains and losses from each day into separate accounts and integrate gains and losses for each day in an account. [19] It can then be interpreted that end-of-day risk-seeking bets is an example of loss aversion where gamblers attempt to equalize their daily account.

Practical implications

Since the inception of the concept, mental accounting has been applied to interpret consumer behavior particularly in the contexts of online shopping, consumer reward points, public taxation policy.

Psychology

Mental accounting is subject to many logical fallacies and cognitive biases, [20] which hold many implications such as overspending. [21]

Credit cards and cash payments

Another example of mental accounting is the greater willingness to pay for goods when using credit cards than cash. [22] Swiping a credit card prolongs the payment to a later date (when we pay our monthly bill) and integrates it to a large existing sum (our bill to that point). [23] This delay causes the payment to stick in our memory less clearly and saliently. Furthermore, the payment is no longer perceived in isolation; rather, it is seen as a (relatively) small increase of an already large credit card bill. For example, it might be a change from $120 to $125, instead of a regular, out-of-pocket $5 cost. And as we can see from our value function, this V(-$125) – V(-$120) is smaller than V(-$5), thus the pain of paying is reduced.

Marketing

Mental accounting can be useful for marketers predict customer response to bundling of pricing and segregation of products. People respond more positively to incentives and costs when gains are segregated, losses are integrated, marketers segregate net losses (the silver lining principle), and integrate net gains. Automotive dealers, for example, benefit from these principles when they bundle optional features into a single price but segregate each feature included in the bundle (e.g. velvet seat covers, aluminum wheels,anti-theft car lock). [24] Cellular phone companies can use principles of mental accounting when deciding how much to charge consumers for a new smartphone and to give them for their trade-in. When the cost of the phone is large and the value of the phone to be traded in is low, it is better to charge consumers a slightly higher price for the phone and return that money to them as a higher value on their trade in. [25] Conversely, when the cost of the phone and the value of the trade-in are more comparable, because consumers are loss averse, it is better to charge them less for the new phone and offer them less for the trade-in. [25]

Public policy

Mental accounting can also be utilized in public economics and public policy. Inherently, the way that people (and therefore tax-payers and voters) perceive decisions and outcomes will be influenced by their process of mental accounting. Policy-makers and public economists could potentially apply mental accounting concepts when crafting public systems, trying to understand and identify market failures, redistribute wealth or resources in a fair way, reduce the saliency of sunk costs, limiting or eliminating the Free-rider problem, or even just when delivering bundles of multiple goods or services to taxpayers. The following examples exist where mental accounting applied to public policy and programs produced positive outcomes.

A good example of the importance of considering mental accounting while crafting public policy is demonstrated by authors Justine Hastings and Jesse Shapiro in their analysis of the SNAP (Supplemental Nutritional Assistance Program). They "argue that these findings are not consistent with households treating SNAP funds as fungible with non-SNAP funds, and we support this claim with formal tests of fungibility that allow different households to have different consumption functions" [26] Put differently, their data supports Thaler's (and the concept of mental accounting's) claim that the principle of fungibility is often violated in practice. Furthermore, they find SNAP to be very effective, calculating a marginal propensity to consume SNAP-eligible food (MPCF) out of benefits received by SNAP of 0.5 to 0.6. This is much higher than the MPCF out of cash transfers, which is usually around 0.1.

The implications of taxation policy on taxpayers was examined through mental accounting principles in Optimal Taxation with Behavioral Insights. [27] The research paper applied the ideology of the three pillars of optimal taxation, and incorporated mental accounting concepts (as well as misperceptions and internalities). Outcomes included novel economic insights, including application of nudges present in optimal taxation frameworks, and challenging the Diamond-Mirrlees productive efficiency result and the Atkinson-Stiglitz uniform commodity taxation proposition, finding they are more likely to fail with behavioral agents. [27]

In the paper Public vs. Private Mental Accounts: Experimental Evidence from Savings Groups in Colombia, it was demonstrated that mental accounting can be exploited to help nudge people towards saving more. [28] The study found that publicly creating a savings goal greatly increased the savings rate of participants when compared to the control and those who set savings goals privately. [28] The power of the labeling effect was observed to vary based on the savings success history of the participants.

Mental accounting plays a powerful role in our decision-making processes. It is important for public policy experts, researchers, and policy-makers continue to explore the ways that it can be utilized to benefit public welfare.

See also

Related Research Articles

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In economics, utility is a measure of the satisfaction that a certain person has from a certain state of the world. Over time, the term has been used in at least two different meanings.

Behavioral economics is the study of the psychological, cognitive, emotional, cultural and social factors involved in the decisions of individuals or institutions, and how these decisions deviate from those implied by classical economic theory.

<span class="mw-page-title-main">Risk aversion</span> Economics theory

In economics and finance, risk aversion is the tendency of people to prefer outcomes with low uncertainty to those outcomes with high uncertainty, even if the average outcome of the latter is equal to or higher in monetary value than the more certain outcome.

<span class="mw-page-title-main">Prospect theory</span> Theory of behavioral economics

Prospect theory is a theory of behavioral economics, judgment and decision making that was developed by Daniel Kahneman and Amos Tversky in 1979. The theory was cited in the decision to award Kahneman the 2002 Nobel Memorial Prize in Economics.

The theory of consumer choice is the branch of microeconomics that relates preferences to consumption expenditures and to consumer demand curves. It analyzes how consumers maximize the desirability of their consumption, by maximizing utility subject to a consumer budget constraint. Factors influencing consumers' evaluation of the utility of goods include: income level, cultural factors, product information and physio-psychological factors.

<span class="mw-page-title-main">Loss aversion</span> Overall description of loss aversion theory

Loss aversion is a psychological and economic concept, which refers to how outcomes are interpreted as gains and losses where losses are subject to more sensitivity in people's responses compared to equivalent gains acquired. Kahneman and Tversky (1992) suggested that losses can be twice as powerful psychologically as gains.

The expected utility hypothesis is a foundational assumption in mathematical economics concerning decision making under uncertainty. It postulates that rational agents maximize utility, meaning the subjective desirability of their actions. Rational choice theory, a cornerstone of microeconomics, builds this postulate to model aggregate social behaviour.

Status quo bias is an emotional bias; a preference for the maintenance of one's current or previous state of affairs, or a preference to not undertake any action to change this current or previous state. The current baseline is taken as a reference point, and any change from that baseline is perceived as a loss or gain. Corresponding to different alternatives, this current baseline or default option is perceived and evaluated by individuals as a positive.

In psychology and behavioral economics, the endowment effect is the finding that people are more likely to retain an object they own than acquire that same object when they do not own it. The endowment theory can be defined as "an application of prospect theory positing that loss aversion associated with ownership explains observed exchange asymmetries."

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In decision theory, the von Neumann–Morgenstern (VNM) utility theorem shows that, under certain axioms of rational behavior, a decision-maker faced with risky (probabilistic) outcomes of different choices will behave as if they are maximizing the expected value of some function defined over the potential outcomes at some specified point in the future. This function is known as the von Neumann–Morgenstern utility function. The theorem is the basis for expected utility theory.

In economics, and in other social sciences, preference refers to an order by which an agent, while in search of an "optimal choice", ranks alternatives based on their respective utility. Preferences are evaluations that concern matters of value, in relation to practical reasoning. Individual preferences are determined by taste, need, ..., as opposed to price, availability or personal income. Classical economics assumes that people act in their best (rational) interest. In this context, rationality would dictate that, when given a choice, an individual will select an option that maximizes their self-interest. But preferences are not always transitive, both because real humans are far from always being rational and because in some situations preferences can form cycles, in which case there exists no well-defined optimal choice. An example of this is Efron dice.

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The uncertainty effect, also known as direct risk aversion, is a phenomenon from economics and psychology which suggests that individuals may be prone to expressing such an extreme distaste for risk that they ascribe a lower value to a risky prospect than its worst possible realization.

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