The Consequences of Zakat for Capital Accumulation

The payment of zakat by the owners of wealth is one of the five pillars of Islam. Many countries operate with no enforcement of the obligation to pay, making zakat a form of voluntary redistribution. We analyze how zakat affects capital accumulation in a model that explicitly recognizes the voluntary nature of zakat. The voluntary payment is modeled using both warm glow and social custom frameworks. These are embedded within an overlapping generations model with heterogenous consumers and endogenous population growth. The results show that zakat can raise the capital–labor ratio when it is motivated by the warm glow but welfare can be nonmonotonic in the strength of the warm glow. In the social custom model, reduced participation can lead to a reduced capital–labor ratio as the rate of zakat is increased.     

Discretionary rewards as a feedback mechanism

This paper studies the use of discretionary rewards in a finitely repeated principal–agent relationship with moral hazard. The key aspect is that rewards have informational content. When the principal obtains a private subjective signal about the agent's performance, she may pay discretionary bonuses to provide credible feedback to the agent. In accordance with the often observed compression of ratings, we show that in equilibrium the principal communicates the agent's interim performance imperfectly, i.e., she does not fully differentiate good and bad performance. Furthermore, we show that small rewards can have a large impact on the agent's effort, provided that the principal's stake in the project is small.     

Discretionary rewards as a feedback mechanism

This paper studies the use of discretionary rewards in a finitely repeated principal–agent relationship with moral hazard. The key aspect is that rewards have informational content. When the principal obtains a private subjective signal about the agent's performance, she may pay discretionary bonuses to provide credible feedback to the agent. In accordance with the often observed compression of ratings, we show that in equilibrium the principal communicates the agent's interim performance imperfectly, i.e., she does not fully differentiate good and bad performance. Furthermore, we show that small rewards can have a large impact on the agent's effort, provided that the principal's stake in the project is small.     

On the relation between ecosystem services,intrinsic value,existence value and economic valuation

Various attempts have been made to amalgamate the concepts of intrinsic value and ecosystem services, often with a stop-over at the economic concept of existence value. These attempts are based on a confusion of concepts, however. In this article, two types of non-use values are distinguished: warm glow value, related to the satisfaction people may derive from altruism towards nature, and existence value, related to the satisfaction people may derive from the mere knowledge that nature exists and originating in the human need for self-transcendence. As benefits to humans, warm glow and existence values can be considered ecosystem services. Neither warm glow value nor existence value represents benefits to nature itself, however. Intrinsic value lies outside the scope of the wide palette of ecosystem services.Although the concept of ecosystem services does not cover benefits to nature and the intrinsic value of such benefits, intrinsic value is not necessarily incompatible with economic valuation. Although a deontological ethics does not allow economic valuation of nature as an end in itself, consequentialism does. In consequentialism, however, intrinsic value is not attributed to nature itself, but to benefits to nature. These benefits can be economically valued on the basis of benefit transfer.     

Consumption dynamics in general equilibrium: A characterisation when markets are incomplete

We introduce a methodology for analysing infinite horizon economies with two agents, one good, and incomplete markets. We provide an example in which an agent's equilibrium consumption is zero eventually with probability one even if she has correct beliefs and is marginally more patient. We then prove the following general result: if markets are effectively incomplete forever then on any equilibrium path on which some agent's consumption is bounded away from zero eventually, the other agent's consumption is zero eventually—so either some agent vanishes, in that she consumes zero eventually, or the consumption of both agents is arbitrarily close to zero infinitely often. Later we show that (a) for most economies in which individual endowments are finite state time homogeneous Markov processes, the consumption of an agent who has a uniformly positive endowment cannot converge to zero and (b) the possibility that an agent vanishes is a robust outcome since for a wide class of economies with incomplete markets, there are equilibria in which an agent's consumption is zero eventually with probability one even though she has correct beliefs as in the example. In sharp contrast to the results in the case studied by Sandroni (2000) [29] and Blume and Easley (2006) [8] where markets are complete, our results show that when markets are incomplete not only can the more patient agent (or the one with more accurate beliefs) be eliminated but there are situations in which neither agent is eliminated.     

A Core‐Equilibrium Convergence in a Public Goods Economy

This paper shows a core‐equilibrium convergence in a public goods economy where consumers' preferences display warm glow effects. We demonstrate that if each consumer becomes satiated to other consumers' provision, then as the economy grows large the core shrinks to the set of Edgeworth allocations. Moreover, we show that an Edgeworth allocation can be decentralized as a warm glow equilibrium.     

Intergenerational Transfer of Human Capital and Optimal Education Policy

We study the design of education policies (subsidies and public education) when parents' investment in education is motivated by warm‐glow altruism and determines the probability that a child has a high ability. The optimal subsidy is not necessarily positive. It is determined by two conflicting terms: a Pigouvian term (warm‐glow altruists do not properly account for the impact of education on future generations) and a “paternalistic” effect (the warm‐glow term may not be fully included in social welfare). Finally, total crowding out of private expenditure (for one of the types) by public education may be desirable.     

Incentives for motivated agents under an administrative constraint

Consider an agent who has an expertise in producing a non-marketable good. This good is valued by a single principal, and there is a verifiable measure of the agent’s performance. Crucially, the agent is intrinsically motivated due to ‘warm glow altruism’. In addition, the agent’s budget, which is controlled by the principal, must not be less than the monetary performance-cost faced by the agent. This gives rise to a limited-liability constraint. It also restricts the agent’s ability to under-report costs. In such environment, we determine the link between the agent’s budget and performance. Our results come in contrast to the received solution of the principal-agent problem and to most in the literature on mission-motivated organisations and public services provision.     

Economics of Social Capital*

The literature on the idea of ‘social capital’ is now enormous. Offering an alternative to impersonal markets and coercive states, the communitarian institutions built around social capital have looked attractive to scholars in the humanities and social sciences. The literature in consequence has a warm glow to it. In this article, I first study the various contexts in which the promises people make to one another are credible and then suggest that the accumulation of social capital is a possible route to creating such a context. I offer a tight definition of social capital – namely, interpersonal networks – so as not to prejudge its ability to enhance human well-being. The links between the microfoundations of social capital and the macroeconomic performance of economies are then studied. I also show that economic theory not only identifies circumstances in which communitarian institutions can function well, but that it also uncovers a dark side, namely, their capicity to permit one group to exploit another within long-term relationships.     

Crowd-out and diversity

Research has shown that altruism is lower in diverse communities. Can this phenomenon be counteracted by government intervention? To answer this question, this paper introduces diversity to the canonical model of “warm glow” giving. Diversity may have two effects on incentives: it may attenuate individuals' altruistic preferences for public goods, and it may “cool off” the warm glow that individuals get from voluntarism. Either of these effects leads to diverse communities having lower levels of public goods, consistent with prior research. However, these effects have opposite implications for the efficacy of government intervention. I then empirically investigate whether government intervention is more effective in diverse communities. For identification, I exploit the Supreme Court-mandated 1991 expansion of the SSI program. Using a new dataset of United Methodist churches from 1984 to 2000, the results show that the expansion of SSI crowded-out charitable spending by churches. The crowd-out estimate for the average church is reasonably large, but this masks significant differences in crowd-out between communities. Crowd-out occurred almost entirely in relatively homogeneous communities; there is only modest evidence of crowd-out in racially diverse communities. Thus diverse communities, while having the lowest levels of altruism, are in this instance the most amenable to government intervention.     

Optimal tax treatment of private contributions for public goods with and without warm glow preferences

Tax-favored contributions for financing some public goods may be a useful part of optimal nonlinear income tax and expenditure policy. There are two sides to the potential gain from subsidized donations. First, for a given level of public good provision, higher private donations from high earners than low earners eases the incentive compatibility constraint for donors and so can raise social welfare. This follows since considering a lower-paid job includes a perception of a drop in public good provision. Second, private donation reduces consumption, easing the resource constraint. This paper explores optimal policy, using first a model with standard preferences and then a model with a warm glow of giving. In addition to showing the conditions for the level of public goods, the paper considers the pattern of optimal subsidization across earnings levels. Analysis of optimal taxation with warm glow preferences is sensitive to the choice of preferences that are relevant for a social welfare evaluation. After considering optimal rules with formulations of social welfare which do and do not include warm glow utility, the paper considers the choice of normative criterion. Like the earlier literature, this paper assumes that organizing private donations is costless while tax collection has a deadweight burden. Since private charitable fundraising is very far from costless, the paper is an exploration of economic mechanisms, not a direct guide to policy.     

Disentangling the sources of pro-socially motivated effort: A field experiment

This paper presents evidence from a field experiment, which aims to identify the two sources of workers' pro-social motivation that have been considered in the literature: warm glow altruism and pure altruism. We employ an experimental design that first measures the level of effort exerted by student workers on a data entry task in an environment that elicits purely selfish behavior and we compare it to effort exerted in an environment that also induces warm glow altruism. We then compare the latter to effort exerted in an environment where both types of altruistic preferences are elicited. We find evidence that women increase effort due to warm glow altruism while we do not find any additional impact due to pure altruism. On the other hand, men in our sample are not responsive to any of the treatments.     

Status quo bias,multiple priors and uncertainty aversion

Motivated by the extensive evidence about the relevance of status quo bias both in experiments and in real markets, we study this phenomenon from a decision-theoretic prospective, focusing on the case of preferences under uncertainty. We develop an axiomatic framework that takes as a primitive the preferences of an agent for each possible status quo option, and provide a characterization according to which the agent considers a full-dimensional set of possible priors and abandons her status quo option only if she finds an alternative that returns a higher expected utility for each of these priors. We then show that, in this framework, the very presence of a status quo induces the agent to be more uncertainty averse than she would be without a status quo option.     

Trust,ability‐to‐pay,and charitable giving

In the literature on privately provided public goods, altruism has been motivated by what contributions can accomplish (public goods philanthropy), by the pleasure of giving (warm‐glow philanthropy), or by the desire to personally make a difference (impact philanthropy). Underlying these motives is the idea that individuals trust that their donations reach their goal. We revisit these models but allow for distrust in the institutional structures involved. An important result we derive is that trust considerations determine whether crowding out is less or more than complete, and we thus open up possibilities in terms of the extent of crowding out not currently available. We also model socially motivated philanthropy when income‐heterogeneous donors take trust and ability‐to‐pay into account. With ability‐to‐pay in social motivation, an important result we obtain is that low‐income donors may contribute more than high‐income donors (in both absolute and percentage‐of‐income terms), giving a potential theoretical foundation to the frequently observed “U‐shaped” pattern of giving.     

Social welfare for an economy of angelic agents

This paper analyzes an economy in which all agents are pursuing the common good (or social welfare) but choices are decentralized, i.e., each agent can choose his/her action in the set of the actions that he/she can perform. One wonders if it is enough the common goal of maximizing social welfare to their will be achieved. The paper examines both the cases in which the choice made by each agent does not directly influence those of other agents, as in the competitive equilibrium analysis, and the case in which there is a direct influence, as in the game theory analyses. In the first case, we get that the common goal of maximizing social welfare is not enough to reach it, but it is necessary to coordinate the actions of individual agents by extending information to redistribute initial endowments and by introducing an appropriate social organization. We get the maximum social welfare without further intervention for the cases describable with the theory of games, but only for games of complete information. If the information is incomplete, some further coordination is generally required.     

Justifiable choice

Most existing decision-making models assume that choice behavior is based on preference maximization even when the preferences are incomplete. In this paper we study an alternative approach – “justifiable choice”: each agent has several preference relations (“justifications”), and she can use each justification in every choice problem. We present a new behavioral property that requires an alternative to be chosen if it is not inferior to all mixtures of chosen alternatives, and show that this property characterizes justifiable choice. The main application of this property yields a multiple-utility representation, which substantially differs from existing related representations. In addition, we obtain a multiple-prior representation, and study the notions of indecisiveness and being more decisive.     

Technical progress in Joan Robinson's view: an attempt at systematisation and formalisation

This paper deals with Joan Robinson's contributions to the issue of technical progress and her attempts at treating this subject in accordance with the Keynesian theory of employment and income distribution, mainly in the long run. The paper aims to review this aspect of her work and to establish a systematisation and a formalisation of her approach. At the same time, the paper exposes the problems she faced—but did not always solve. Looking through her main contributions, the paper concludes that she used different criteria for the classification of innovations and that they depended on the specific situations described by the models in which she used the classification.     

Institutions, motivations and public goods: An experimental test of motivational crowding

Contributions to public goods can be motivated by intrinsic factors such as warm glow altruism and fairness, as well as extrinsic incentives such as sanctions and payments. However, psychological studies suggest that formal extrinsic incentives may crowd out intrinsic motivations. In an experimental study of individual contributions to a public good we find that suasion crowded in voluntary contributions, while an extrinsic incentive in the form of a regulation led to crowding out. This has implications for the design of public policy where ranges of motivations are present.     

Eliciting beliefs: Proper scoring rules,incentives, stakes and hedging

Proper Scoring Rules (PSRs) are popular incentivized mechanisms to elicit an agent's beliefs. This paper combines theory and experiment to characterize how PSRs bias reported beliefs when (i) the PSR payments are increased, (ii) the agent has a financial stake in the event she is predicting, and (iii) the agent can hedge her prediction by taking an additional action. In contrast with previous literature, the PSR biases are characterized for all PSRs and all risk averse agents. Our results reveal complex distortions of reported beliefs, thereby raising concerns about the ability of PSRs to recover truthful beliefs in general decision-making environments.     

The individual and the market: Paul Samuelson on (homothetic) Santa Claus economics

Paul Samuelson often used the term “Santa Claus economics” for mathematical models with empirically unrealistic assumptions. I focus on one particular member of the Santa Claus family that Samuelson was very sceptical about: homothetic general equilibrium models (where all agents have identical homothetic preferences). I argue that Samuelson's concerns about these models provide insights into how he viewed the relationship between the individual and the market, a relationship that has implications for not only his economic theorising, but also his broader political–economic vision. His criticisms are also relevant to some ongoing debates within contemporary economic theory.