The social discount rate – the rate at which future benefit flows from government investment are discounted to present value – has been a frequent subject of technical debate among professional economists. From a broader perspective, however, the selection of an appropriate rate enjoins consideration of questions that define the very contours of our public philosophy. It carries implicit assumptions about the nature of citizenship, the relation between public and private spheres, and, most singularly, the status of a political (...) society as it is located in time. A key determinant of intertemporal economic allocation, the social discount rate provides a unique registry of a polity's historical consciousness and perceptions of its intergenerational obligations. Yet the highly technical nature of the debate over the discount rate has proven inhospitable to scholars otherwise inclined to investigate its ethical dimensions. Some, notably A. K. Sen, have begun to address these philosophical issues, though much territory remains to be explored. (shrink)

Climate change is projected to have very severe impacts on future generations. Given this, any adequate response to it has to consider the nature of our obligations to future generations. This paper seeks to do that and to relate this to the way that inter-generational justice is often framed by economic analyses of climate change. To do this the paper considers three kinds of considerations that, it has been argued, should guide the kinds of actions that one generation should take (...) if it is to treat both current and future people equitably. In particular it examines the case for what has been termed pure time discounting, growth discounting and opportunity cost discounting; and it assesses their implications for climate policy. It argues that none of these support the claims of those who think they give us reason to delay aggressive mitigation policies. It also finds, however, that the second kind of argument can, in certain circumstances, provide support for passing on some of the costs of mitigation to future generations. (shrink)

Ethics, Policy & Environment, Volume 15, Issue 1, Page 45-50, March 2012.

This research investigates the influence that consumers’ perceptions of retail business ethics have on their responses when retailers either create social discount spaces or do not. Using scenarios to imply these social practices and structural equation modeling to test the hypotheses among a sample of 689 respondents, the authors find that consumers’ perceptions of retail business ethics have positive effects on consumer loyalty, both directly and through consumer trust, as well as positive, strong influences on the retailer’s corporate (...) social responsibility and corporate reputation. Furthermore, consumers’ perceptions of retail business ethics exert a stronger effect on consumer trust in integrated social discount spaces, though social discount practices do not affect the link between such perceptions and loyalty. Compared with when the retailer does not offer discount space, collaborative and integrated social discount spaces have weaker effects on trust and loyalty to the retailer. These findings have several notable theoretical and practical implications. (shrink)

One’s generosity to others declines as a function of social distance, which is known as social discounting. We examined cultural similarities and differences in social discounting and the mediating roles of the two aspects of interdependence (self-expression and distinctiveness of the self) as well as the two aspects of independence (harmony-seeking and rejection avoidance). Using the same procedure that previous researchers used to test North Americans, Study 1 showed that compared to North Americans, Japanese discount (...) more steeply a partner’s outcomes compared to their own future outcomes, whereas the decrease in the subjective value of the partner’s outcomes accelerates less as a function of social distance. To examine the cultural similarities and differences in social discounting in more detail, Study 2 tested Japanese and Germans and found that the hyperbolic with exponent model fitted the participants’ discounting behaviors better than the other models, except for the loss condition in Germans where the utility of the q-exponential model was indicated. Moreover, although the social discounting rate was higher in Japanese than in Germans, the cultural difference was limited to the gain frame. However, the decline in a person’s generosity accelerated less as a function of social distance in Japanese than in Germans. Furthermore, the cultural difference in the social discounting in gains was mediated by the level of harmony-seeking, which was higher in Germans than in Japanese. Implications for individuals’ generosity against the backdrop of cultural characteristics are discussed. (shrink)

Altruism can be understood in terms of traditional principles of reinforcement if an outcome that is beneficial to another person reinforces the behavior of the actor who produces it. This account depends on a generalization of reinforcement across persons and might be more amenable to experimental investigation than the one proposed by Rachlin.

Humans discount rewards as a function of the delay to their receipt. This tendency is referred to as delay discounting and has been extensively researched in the last decades. The magnitude effect and the trait effect are two phenomena which have been consistently observed for a variety of reward types. Here, we wanted to investigate if these effects also occur in the context of the novel but widespread reward types of Instagram followers and likes and if delay discounting (...) of these outcomes is related to self-control and Instagram screen time. In a within-subject online experiment, 214 Instagram users chose between smaller, immediate and larger, delayed amounts of hypothetical money, Instagram followers and likes. First, we found that the magnitude effect also applies to Instagram followers and likes. Second, delay discounting of all three reward types was correlated, providing further evidence for a trait influence of delay discounting. Third, no relationships were found between delay discounting and self-control as well as Instagram screen time, respectively. However, a user’s average like count was related to delay discounting of Instagram likes. (shrink)

Economic policy evaluations require social welfare functions for variable-size populations. Two important candidates are critical-level generalized utilitarianism (CLGU) and rank-discounted critical-level generalized utilitarianism, which was recently characterized by Asheim and Zuber (2014) (AZ). AZ introduce a novel axiom, existence of egalitarian equivalence (EEE). First, we show that, under some uncontroversial criteria for a plausible social welfare relation, EEE suffices to rule out the Repugnant Conclusion of population ethics (without AZ’s other novel axioms). Second, we provide a new characterization (...) of CLGU: AZ’s set of axioms is equivalent to CLGU when EEE is replaced by the axiom same-number independence. (shrink)

The social rate of discount--that is, the way decision makers today evaluate future consequences of collective activity--raises difficult issues of intergenerational justice. When benefits are discounted at the present rate the United States government requires, serious efforts to promote public health over the long term will fail cost-benefit tests. No consensus exists among theorists to establish fair rates; philosophers support discounting with economic arguments that economists reject, while economists no less paradoxically support the concept using philosophical arguments that (...) philosophers disavow. A new emphasis on the role of consumers' and citizens' time preferences, however, will keep open rather than close debates on the social discount rate. (shrink)

Concern for the rapidly growing scale and intensity of the human exploitation of the environment, in particular the alienation of natural ecosystems, but also resource exhaustion, pollution, and congestion, leads one to wonder about the short time. horizons allowed for in decision making. Time preference is dictated by the rate of interest, allowing in practice a horizon often not exceeding several decades. I argue that this is unsatisfactory. Some minimal social rate of discount should not be enforced. Instead, it (...) is more feasible to set absolute environmental standards, thereby introducing quantity constraints on our decision making, within which time preference can be permitted to find its own level. This acknowledges that the myopia of human vision may not be a flaw but rather a biological design which has served us weIl in evolution. It may, therefore, be better to change the rules by introducing self-imposed collective constraints than to try to change the shortsightedness of people in their day-to-day grass-roots decision making. (shrink)

Concern for the rapidly growing scale and intensity of the human exploitation of the environment, in particular the alienation of natural ecosystems, but also resource exhaustion, pollution, and congestion, leads one to wonder about the short time. horizons allowed for in decision making. Time preference is dictated by the rate of interest, allowing in practice a horizon often not exceeding several decades. I argue that this is unsatisfactory. Some minimal social rate of discount should not be enforced. Instead, it (...) is more feasible to set absolute environmental standards, thereby introducing quantity constraints on our decision making, within which time preference can be permitted to find its own level. This acknowledges that the myopia of human vision may not be a flaw but rather a biological design which has served us weIl in evolution. It may, therefore, be better to change the rules by introducing self-imposed collective constraints than to try to change the shortsightedness of people in their day-to-day grass-roots decision making. (shrink)

Employing theoretical resources from Transactional Analysis and drawing from interviews with managers dealing with social or environmental issues in their role, we explain how CSR activity provides a context for dramas in which actors may ignore, or discount aspects of self, others, and the contexts of their work as they maintain and reproduce the roles of Rescuers, Persecutors and Victims. In doing so, we add to knowledge about CSR by providing an explanation for how the contradictions of CSR are (...) avoided in practice even when actors may be aware of them. Specifically, we theorise how CSR work can produce dramatic stories where adversity is apparently overcome, whilst little is actually achieved at the social level. We also add to the range of psychoanalytic tools used to account for organisational behaviours, emphasising how TA can explain the relational dynamics of CSR. (shrink)

When assessing the cost effectiveness of health care programmes, health economists typically presume that distant events should be given less weight than present events. This article examines the moral reasonableness of arguments advanced for positive discounting in cost-effectiveness analysis both from an intergenerational and an intrapersonal perspective and assesses if arguments are equally applicable to health and monetary outcomes. The article concludes that behavioral effects related to time preferences give little or no reason for why society at large should (...) favour the present over the future when making intergenerational choices regarding health. The strongest argument for discounting stems from the combined argument of diminishing marginal utility in the presence of growth. However, this hinges on the assumption of actual growth in the relevant good. Moreover, current modern democracy may be insufficiently sensitive to the concerns of future generations. The second part of the article categorises preference failures (which justify paternalistic responses) into two distinct groups, myopic and acratic. The existence of these types of preference failures makes elicited time preferences of little normative relevance when making decisions regarding the social discount rate, even in an intrapersonal context. As with intergenerational discounting, the combined arguments of growth and diminishing marginal utility offer the strongest arguments for discounting in the intrapersonal context. However, there is no prima facie reason to assume that this argument should apply equally to health and monetary values. To be sure, selecting an approach towards discounting health is a complex matter. However, the life-or-death implications of any approach require that the discussion not be downplayed to merely a technical matter for economists to settle. (shrink)

This article is a critical survey of the debate over the value of the social discount rate, with a particular focus on climate change. The ma- jority of the material surveyed is from the economics rather than from the philosophy literature, but the emphasis of the survey itself is on founda- tions in ethical and other normative theory rather than highly technical details. I begin by locating the standard approach to discounting within the overall landscape of ethical theory, (...) and explaining the assumptions and simplifications that are needed in order to arrive at the model that is standard in the discounting literature. The article then covers the general theory of the Ramsey equation and its relationship to observed interest rates, arguments for and against a positive rate of pure time preference, the consumption elasticity of utility, and the effect of various sorts of uncertainty on the discount rate. Finally, it turns specifically to the ap- plication of this debate to the case of climate change, focussing on the recent controversy over the low discount rate used in the Stern Review of the Economics of Climate Change. (shrink)

The willingness to trade off large but ill-defined future consequences for immediate work characterizes social problems such as environmental sustainability. This commentary argues that important applications of behavioral models of self-control are being overlooked in the experimental literature. Tying the experimental literature to longterm health, environmental, and other risks makes the experimental work more germane, and raises new research questions for experimental modeling.

I argue that the use of a social discount rate to assess the consequences of climate policy is unhelpful and misleading. I consider two lines of justification for discounting: (i) ethical arguments for a "pure rate of time preference" and (ii) economic arguments that take time as a proxy for economic growth and the diminishing marginal utility of consumption. In both cases I conclude that, given the long time horizons, distinctive uncertainties, and particular costs and benefits at stake (...) in the climate context, discount rates are at best a poor proxy for the normative considerations they are meant to represent. (shrink)

This paper distinguishes between five different approaches to social discount rates in climate change economics, criticizes two of these, and explains how the other three are to some degree mutually compatible. It aims to shed some new light on a longstanding debate in climate change economics between so-called “descriptivists” and “prescriptivists” about social discounting. The ultimate goal is to offer a sketch of the conceptual landscape that makes visible some important facets of the debate that very often (...) go unacknowledged. (shrink)

Testimonial injustice occurs when bias against the credibility of certain social identities results in discounting of their contributions to deliberations. In this analysis, we describe testimonial injustice against women and how it figures in macroallocation procedure. We show how it harms women as deliberators, undermines the objective of inclusivity in macroallocation and affects the justice of resource distributions. We suggest that remedial action is warranted in order to limit the effects of testimonial injustice in this context, especially on (...) marginalised and disadvantaged groups, and propose three areas for action, whose implementation might feasibly be achieved by those immediately involved in macroallocation. (shrink)

Exponential discounted utility theory provides the normative standard for future discounting as it is employed throughout the social sciences. Tracing the justification for this standard through economics, philosophy and psychology, I’ll make what I believe is the best case one can for it, showing how a non-arbitrariness assumption and a dominance argument together imply that discounting ought to be exponential. Ultimately, however, I don’t find the case compelling, as I believe it is deeply flawed. Non-exponential temporal (...) class='Hi'>discounting is often rational–indeed, the paragon of rationality. If this is correct, it’s an important point when considering policy interventions. Instead of trying to “fix” non-exponetial discounting because it is irrational and associated with negative life outcomes, we might instead focus attention on why the conditions obtain that make such discounting rational. (shrink)

The social discount rate typically consists of two components: differences in the marginal utility of consumption across time, and the pure time preference rate as applied to cardinal utility. Within this framework, intragenerational and intergenerational time preference rates must be the same, if we are to avoid strongly counterintuitive results. Both rates, however, can be plausibly equal at zero rather than at a positive level; pure time preference should not necessarily be applied to cardinal utility, even when we apply (...) it to goods. The other component of the discount rate, the marginal utility of consumption, is appropriate only for very small changes in individual wealth; this assumption does not match most of the intergenerational scenarios in question. I conclude that economics does not provide a prima facie case for a positive rate of intergenerational discount for most policy issues. (shrink)

An often-suggested way of giving content to the view that adolescent offenders should be punished more leniently than adult offenders has been to advocate the idea of a general youth discount for adolescents. Several theorists hold that a youth discount can be justified on a retributivist ground. But is the idea of a general youth discount consistent with the basic idea of giving individual offenders their just deserts? This article examines three arguments that have been presented to this effect. It (...) is argued that the arguments are implausible and that the idea of a retributively justified general youth discount for adolescent offenders is unpersuasive. (shrink)

This paper challenges the conventional wisdom dominating the social sciences and philosophy regarding temporal discounting, the practice of discounting the value of future utility when making decisions. Although there are sharp disagreements about temporal discounting, a kind of standard model has arisen, one that begins with a normative standard about how we should make intertemporal comparisons of utility. This standard demands that in so far as one is rational one discounts utilities at future times with an (...) exponential discount function. Tracing the justification for this standard through economics, philosophy and psychology, I’ll make what I believe is the best case one can for it, showing how a non-arbitrariness assumption and a dominance argument together imply that discounting ought to be exponential. Ultimately, however, I don’t find the case compelling. Non-exponential temporal discounting is often rational. If this is correct, Instead of trying to ‘fix’ non-exponential discounting because it is irrational and associated with negative life outcomes, we might instead focus attention on why the conditions obtain that make such discounting rational. (shrink)

Recent research introduced the Discounting Inventory that allows the measurement of individual differences in the delay, probabilistic, effort, and social discounting rates. The goal of this investigation was to determine several aspects of the reliability of the Discounting Inventory using the responses of 385 participants. Two types of reliability are of interest. Internal consistency and test-retest stability. A secondary aim was to extend such reliability measures beyond the non-clinical participant. The current study aimed to measure the (...) reliability of the DI in a nicotine-dependent individuals and non-nicotine-dependent individuals. It is concluded that the internal consistency of the DI is excellent, and that the test-retest reliability results suggest that items intended to measure three types of discounting were likely testing trait, rather than state, factors, regardless of whether “non-smokers” were included in, or excluded from, the analyses. With these cautions in mind, however, the psychometric properties of the DI appear to be very good. (shrink)

According to Craig Callender [2022], the ‘received view’ across the social sciences is that, when it comes to time and preference, only exponential time discounting is rational. Callender argues that this view is false, even pernicious. Here I endorse what I take to be Callender’s main argument, but only in so far as the received view is understood in a particular way. I go on to propose a different way of understanding the received view that makes it true. (...) In short: When time discounting is suitably conceived, the exponential form of the discounting function is indeed uniquely rational. (shrink)

Reinforcement schemes are a class of non-Markovian stochastic processes. Their non-Markovian nature allows them to model some kind of memory of the past. One subclass of such models are those in which the past is exponentially discounted or forgotten. Often, models in this subclass have the property of becoming trapped with probability 1 in some degenerate state. While previous work has concentrated on such limit results, we concentrate here on a contrary effect, namely that the time to become trapped may (...) increase exponentially in 1/x as the discount rate, 1− x, approaches 1. As a result, the time to become trapped may easily exceed the lifetime of the simulation or of the physical data being modeled. In such a case, the quasi-stationary behavior is more germane. We apply our results to a model of social network formation based on ternary (three-person) interactions with uniform positive reinforcement. (shrink)

We present a new axiomatization of the classical discounted expected utility model, which is primarily used as a decision model for consumption streams under risk. This new axiomatization characterizes discounted expected utility as a model that satisfies natural extensions of standard axioms as in the one-period case and two additional axioms. The first axiom is a weak form of time separability. It only requires that the choice between certain constant consumption streams and lotteries should be made by just taking into (...) account the time periods where the consumption is different. The second axiom, the time–probability equivalence, requires that risk and time preferences basically work in the same way. Moreover, we prove that preferences satisfying the natural extensions of the standard axioms as well as the first axiom can be represented in a simple form relying on three functions linked to the risk or time preferences in simple situations. Finally, we illustrate that several examples that are not fully time separable satisfy all our axioms except for the time–probability equivalence. (shrink)

People seem to have pure time preferences about trade-offs concerning their own pleasures and pains, and such preferences contribute to estimates of people's individual time discount rate. Do pure time preferences also matter to interpersonal welfare trade-offs, including those concerning the welfare of future generations? Most importantly, should the intergenerational time discount rate include a pure time preference? Descriptivists claim that the intergenerational discount rate should reflect actual people's revealed preferences, and thus it should include a pure time preference. Prescriptivists (...) claim that the intergenerational discount rate should be based on moral analysis, and thus they (often) claim that the rate of pure time preference should be zero. I argue that regardless of which view is correct, a focus on pure time preference is misplaced. First, the most plausible interpretation of descriptive preferences for intergenerational trade-offs is that people are socially biased and not time biased. Second, social bias is superior to time bias as a prescriptive reason to discount the welfare of future people. Third, recent advances in measuring social bias as a social discount rate make social bias a viable replacement for time bias in economic analyses of intergenerational welfare trade-offs. (shrink)

When probability discounting (or probability weighting), one multiplies the value of an outcome by one's subjective probability that the outcome will obtain in decision-making. The broader import of defending probability discounting is to help justify cost-benefit analyses in contexts such as climate change. This chapter defends probability discounting under risk both negatively, from arguments by Simon Caney (2008, 2009), and with a new positive argument. First, in responding to Caney, I argue that small costs and benefits need (...) to be evaluated, and that viewing practices at the social level is too coarse-grained. Second, I argue for probability discounting using a distinction between causal responsibility and moral responsibility. Moral responsibility can be cashed out in terms of blameworthiness and praiseworthiness, while causal responsibility obtains in full for any effect which is part of a causal chain linked to one's act. With this distinction in hand, unlike causal responsibility, moral responsibility can be seen as coming in degrees. My argument is, given that we can limit our deliberation and consideration to that which we are morally responsible for and that our moral responsibility for outcomes is limited by our subjective probabilities, our subjective probabilities can ground probability discounting. (shrink)

The social cost of carbon (SCC) is a central concept in climate change economics. This chapter explains the SCC and investigates it philosophically. As is widely acknowledged, any SCC calculation requires the analyst to make choices about the infamous topic of discount rates. But to understand the nature and role of discounting, one must understand how that concept—and indeed the SCC concept itself—is yoked to the concept of a value function, whose job is to take ways the world (...) could be across indefinite timespans and to rank them from better to worse. A great deal, therefore, turns on the details of the value function and on just what is meant by “better” and “worse.” This chapter seeks to explicate these and related issues, and then to situate them within the evolving landscape of federal climate policy in the United States. (shrink)

What are our political obligations to future generations? How does morality suggest that we weight current interests against future interests? Do politics or markets place greater weight upon interests in the very distant future? How should we discount future costs and benefits?

I find much to like in Craig Callender's [2022] arguments for the rational permissibility of non-exponential time discounting when these arguments are viewed in a conditional form: viz., if one thinks that time discounting is rationally permissible, as the social scientist does, then one should think that non-exponential time discounting is too. However, time neutralists believe that time discounting is rationally impermissible, and thus they take zero time discounting to be the normative standard. The (...) time neutralist rejects time discounting because they think it is rationally impermissible to prefer to live a worse life in expectation because of arbitrariness. Callender’s attack on the time-neutralist position is the following: the time-neutralist’s non-arbitrariness intuition assumes the existence of nonexistent ‘pure’ time preferences. In response, I aim to clarify the time-neutralist position and show that the non-arbitrariness argument does not rely on the existence of pure time preferences. Instead, the debate between time neutralism and permissivism about time discounting boils down to a methodological question: can we ever criticize the content of preferences? If so, we should embrace time neutralism. (shrink)

Tversky and Koehler's support theory attempts to explain why probability judgments are affected by the manner in which formally similar events are described. Support theory suggests that as the explicitness of a description increases, an event will be judged to be more likely. In the present experiment, experienced decision-makers from large, international accounting firms were given case-specific information about an audit client and asked to provide a series of judgments regarding the perceived likelihood of events. Unpacking a hypothesis into four (...) formally equivalent hypotheses more than doubled its perceived likelihood. These results are largely consistent with support theory, extending its generalizability to applied contexts involving business professionals. Further, the paper finds that task-specific factors, a previously untested area, can also affect support theory interpretations. (shrink)

The Discounting Inventory, originally developed in polish language, allows the measurement of individual differences in the delay, probabilistic, effort, and social discounting rates. The present study attempted to validate the DI’s psychometric properties using German university students and to compare the results to those from a sample of Polish university students. Over four hundred participants completed the DI and traditional discounting measures. A confirmatory factor analyses indicated that the original four-factor model of the DI provided an (...) excellent fit for the German data and internal consistency was high. These outcomes were similar, if not superior, to those from the Polish sample. DI scores strongly correlated with traditional discounting measures scores in both samples, replicating previous results. These findings indicate that the DI is a valid measure for use in a sample from another cultural setting, which is potentially useful to both researchers and practitioners. (shrink)

How should one discount utility across time? The conventional wisdom in social science is that one should use an exponential discount function. Such a function is a representation of the axioms that provide a well-defined utility function plus a condition known as stationarity. Yet stationarity doesnt really have much intuitive normative pull on its own. Here I try to cast it in a normative glow by deriving stationarity from two explicitly normative premises, both suggested by the philosophical thesis of (...) temporal neutralism. Putting the argument in this form helps us better understand exponential discounting and challenges to it. (shrink)

A central point of debate over environmental policies concerns how future costs and benefits should be assessed. The most commonly used method for assessing the value of future costs and benefits is economic discounting. One often-cited justification for discounting is uncertainty. More specifically, it is risk aversion coupled with the expectation that future prospects are more risky. In this paper I argue that there are at least two reasons for disputing the use of risk aversion as a justification (...) for discounting when dealing with longterm decisions, one technical and one ethical. Firstly, I argue that technically, it implies an inconsistency between theory and practice. And secondly, I argue that discounting for uncertainty relies on a form of individualism which, while reasonable in standard microeconomic theory where an agent chooses how to spread her own consumption over her own lifetime, is inappropriate in the context of intergenerational social decisions. (shrink)

We analyze the role of ethical values in the determination of the social cost of carbon, arguing that the familiar debate about discounting is too narrow. Other ethical issues are equally important to computing the social cost of carbon, and we highlight inequality, risk, and population ethics. Although the usual approach, in the economics of cost-benefit analysis for climate policy, is confined to a utilitarian axiology, the methodology of the social cost of carbon is rather flexible (...) and can be expanded to a broader set of social-welfare approaches. [Open access]. (shrink)

Ramsey famously condemned discounting “future enjoyments” as “ethically indefensible”. Suppes enunciated an equity criterion which, when social choice is utilitarian, implies giving equal weight to all individuals’ utilities. By contrast, Arrow (Contemporary economic issues. International Economic Association Series. Palgrave Macmillan, London, 1999a; Discounting and Intergenerational Effects, Resources for the Future Press, Washington DC, 1999b) accepted, perhaps reluctantly, what he called Koopmans’ (Econometrica 28(2):287–309, 1960) “strong argument” implying that no equitable preference ordering exists for a sufficiently unrestricted domain (...) of infinite utility streams. Here we derive an equitable utilitarian objective for a finite population based on a version of the Vickrey–Harsanyi original position, where there is an equal probability of becoming each person. For a potentially infinite population facing an exogenous stochastic process of extinction, an equitable extinction biased original position requires equal conditional probabilities, given that the individual’s generation survives the extinction process. Such a position is well-defined if and only if survival probabilities decline fast enough for the expected total number of individuals who can ever live to be finite. Then, provided that each individual’s utility is bounded both above and below, maximizing expected “extinction discounted” total utility—as advocated, inter alia, by the Stern Review on climate change—provides a coherent and dynamically consistent equitable objective, even when the population size of each generation can be chosen. (shrink)

Ramsey famously condemned discounting “future enjoyments” as “ethically indefensible”. Suppes enunciated an equity criterion which, when social choice is utilitarian, implies giving equal weight to all individuals’ utilities. By contrast, Arrow accepted, perhaps reluctantly, what he called Koopmans’ :287–309, 1960) “strong argument” implying that no equitable preference ordering exists for a sufficiently unrestricted domain of infinite utility streams. Here we derive an equitable utilitarian objective for a finite population based on a version of the Vickrey–Harsanyi original position, where (...) there is an equal probability of becoming each person. For a potentially infinite population facing an exogenous stochastic process of extinction, an equitable extinction biased original position requires equal conditional probabilities, given that the individual’s generation survives the extinction process. Such a position is well-defined if and only if survival probabilities decline fast enough for the expected total number of individuals who can ever live to be finite. Then, provided that each individual’s utility is bounded both above and below, maximizing expected “extinction discounted” total utility—as advocated, inter alia, by the Stern Review on climate change—provides a coherent and dynamically consistent equitable objective, even when the population size of each generation can be chosen. (shrink)

Discounting is a manifestation of behavioral impulsivity, which is closely related to self-regulation processes. The decision-making process for intertemporal choices is governed by the inhibition of impulses, which can influence both risk and time-related attitudes. This paper utilizes self-reported measures of risk, impatience, and impulsivity attitudes to examine their impact on the implicit discount rate used when weighing the current purchase cost against future energy savings of appliances. It analyzes and tests the interplay between these attitudes using specific functional (...) forms and causal models. The results highlight the role of risk, impatience and impulsivity on the discount rate and the biases that arise from omitting impulsive attitudes. In addition, other factors such as environmental and social preferences, attitudes, and financial constraints contribute to the implicit discount rate. (shrink)

Income is a primary determinant of social mobility, career progression, and personal happiness. It has been shown to vary with demographic variables like age and education, with more oblique variables such as height, and with behaviors such as delay discounting, i.e., the propensity to devalue future rewards. However, the relative contribution of each these salary-linked variables to income is not known. Further, much of past research has often been underpowered, drawn from populations of convenience, and produced findings that (...) have not always been replicated. Here we tested a large (n = 2,564), heterogeneous sample, and employed a novel analytic approach: using three machine learning algorithms to model the relationship between income and age, gender, height, race, zip code, education, occupation, and discounting. We found that delay discounting is more predictive of income than age, ethnicity, or height. We then used a holdout data set to test the robustness of our findings. We discuss the benefits of our methodological approach, as well as possible explanations and implications for the prominent relationship between delay discounting and income. (shrink)

_ Source: _Page Count 28 Recent debates over climate change policy have made it clear that the choice of a social discount rate has enormous consequences for the amount of mitigation that will be recommended. The social discount rate determines how future costs are to be compared to present costs. Philosophers, however, have been almost unanimous in endorsing the view that the only acceptable social rate of time preference is zero, a view that, taken literally, has either (...) absurd or extremely radical implications. The first goal of this paper is to show that the standard arguments against temporal preference are much less persuasive than they are usually taken to be. The second goal is to explore two different avenues of argument that could be adopted, in order to show that temporal discounting of welfare may be permissible. The first involves simply an application of the method of reflective equilibrium, while the second involves consideration of the way that our abstract moral commitments are institutionalized. (shrink)

Recent debates over climate change policy have made it clear that the choice of a social discount rate has enormous consequences for the amount of mitigation that will be recommended. The social discount rate determines how future costs are to be compared to present costs. Philosophers, however, have been almost unanimous in endorsing the view that the only acceptable social rate of time preference is zero, a view that, taken literally, has either absurd or extremely radical implications. (...) The first goal of this paper is to show that the standard arguments against temporal preference are much less persuasive than they are usually taken to be. The second goal is to explore two different avenues of argument that could be adopted, in order to show that temporal discounting of welfare may be permissible. The first involves simply an application of the method of reflective equilibrium, while the second involves consideration of the way that our abstract moral commitments are institutionalized. (shrink)

Integrated assessment models (IAMs) of climate and the economy provide estimates of the social cost of carbon and inform climate policy. With the Nested Inequalities Climate Economy model (NICE) (Dennig et al. PNAS 112:15,827–15,832, 2015), which is based on Nordhaus’s Regional Integrated Model of Climate and the Economy (RICE), but also includes inequalities within regions, we investigate the comparative importance of several factors—namely, time preference, inequality aversion, intraregional inequalities in the distribution of both damage and mitigation cost and the (...) damage function. We do so by computing optimal carbon price trajectories that arise from the wide variety of combinations that are possible given the prevailing range of disagreement over each factor. This provides answers to a number of questions, including Thomas Schelling’s conjecture that properly accounting for inequalities could lead the inequality aversion parameter to have an effect opposite to what is suggested by the Ramsey equation. (shrink)

This paper examines explore the issues of intergenerational equity raised by climate change. A number of different reasons have been suggested as to why current generations may legitimately favor devoting resources to contemporaries rather than to future generations. These - either individually or jointly - challenge the case for combating climate change. In this paper, I distinguish between three different kinds of reason for favoring contemporaries. I argue that none of these arguments is persuasive. My answer in each case appeals (...) to the concept of human rights. It maintains that a human rights-centered perspective to climate change enables us to address each of these reasons. (shrink)

This study proposes a model of non-unitary time discounting and examines its welfare implications. A key feature of our model lies in the disparity of time discounting between multiple distinct goods, which induces an individual’s preference reversals even though she normally discounts her future utilities for each good. After characterizing the time-consistent decision-making by such an individual, we compare welfare achieved in the market economy and welfare in the planner’s allocation from the perspective of all selves across time. (...) Under certain situations, the selves in early periods strictly prefer the social planner’s allocation, whereas the selves in future periods strictly prefer the market equilibrium. Therefore, the welfare implications of our model are quite different from those in the canonical discounting model and in models of other time-inconsistent preferences. (shrink)

In this Article I will challenge the tendency to discount the severity of domestic homicide, a phenomenon I call "the domestic discount." I will argue against automatic mitigation-the imputation of provocation or diminished capacity-simply or merely because the relationship" between victim and defendant is domestic or sexually intimate. I will argue that the traditional hot blood/cold blood dichotomy is an imperfect guide to the moral grading of homicide offenses. In particular, reliance on it has led to the under evaluation of (...) the seriousness of some domestic homicides. It is my contention, or hypothesis, that the conclusions I draw from the study of capital domestic cases can be generalized to the entire domain of domestic homicides: If homicide laws were purged of patriarchal values, the remaining principles that underlie our grading of homicide offenses would be consistent with the rejection of a domestic discount; the worst domestic murders like the worst predatory murders would rank among the most reprehensible crimes. (shrink)