Discount functions and self-control problems

In this paper we propose a new strategy for comparing the behavior of a hyperbolic discounter who possesses self-control problems to an exponential discounter who does not. Our strategy controls for inherent differences in overall levels of impatience across discount functions, which thereby allows us to isolate the pure effect of self-control problems. We argue that self-control problems, in their pure form as we identify them, can have a very surprising effect on intertemporal choices. Our method reveals that differences in decision making that could be attributed to self-control problems are at least partly (and perhaps entirely) just an artifact of an uncontrolled comparison.     

Inter-temporal choices with temporal reference dependence

I develop an intertemporal choice model for rational deviators whose preferences depend not only on their actual consumption but also on comparison to their beliefs about the optimal consumption. The standard decision maker is loss averse with respect to this belief-dependent reference point. When psychologically weighted loss aversion is low, a decision maker deviates from the standard intertemporal choice behavior and over-consumption, as well as the alternative possibility of under-consumption can be rationalized. When the decision maker has time-varying degrees of loss aversion, he re-optimizes the consumption plan through adjusted beliefs as subsequent selves realize that past decision for the present period is no longer optimal. In the dynamic model, I solve for consistent intertemporal optimization rules by which a dynamic deviator should meet rational intertemporal consistency at each point in time. Finally, I demonstrate that the dynamic reference dependent model can solve a puzzling feature in lifecycle consumption data.     

THE RISK‐FREE RATE IN A FINITE HORIZON MODEL WITH BEQUESTS

This paper studies the risk‐free rate in an overlapping generations economy with bequests. It is shown that the risk‐free rate depends on risk aversion, the elasticity of intertemporal substitution, the share of wealth invested in human wealth, life expectancy, and the preference for bequests. In a standard life‐cycle context, mortality increases the subjective time rate of discount, and thus increases the compensation required to postpone consumption. This latter effect is offset in a bequest‐driven model of the type considered here, leading to much more powerful income effects. In this sense, the model provides a bequest‐motive explanation for the risk‐free rate puzzle put forward by Weil in 1989.     

Rates of return to public and private capital: new estimates using nonlinear Euler equations

Results obtained by Otto and Voss show that public investment undertaken in Australia over recent decades satisfies conditions for intertemporal efficiency. This paper confirms this result, although lower output elasticities and rates of return to private and public capital are obtained. The reason for these results is that the earlier work is extended by estimating the parameter related to the elasticity of intertemporal substitution that was earlier restricted to a specific value. In fact, it is shown here that it is possible to obtain an economically reasonable (and statistically significant) estimate of this parameter by assuming that the stochastic discount factor for the representative firm is the same as for the representative consumer and equal to a gross real interest rate.     

A NEW APPROACH TO ASSET INTEGRATION: METHODOLOGY AND MYSTERY

Abstract. This paper develops a new methodology to test financial market integration. Our technique is based on an intertemporal asset‐pricing model, and relies on estimating and comparing expected discount rates across asset markets. Expected discount rates are allowed to vary freely over time, constrained only by the fact that they are equal across assets. Assets are allowed to have very general risk characteristics, and are constrained only by a linear factor model of covariances with the discount rate over short time periods. We provide a variety of domestic and international empirical illustrations of our technique, and find surprisingly little evidence of integration.     

Commodity Rates of Interest and Intertemporal Substitution in Commodity Demand and Consumption

This paper examines the role of commodity own rates of interest in intertemporal analysis of consumer behaviour and presents a disaggregate analysis of intertemporal substitution in commodity demand and consumption. Commodity rates of interest are defined from the Euler equations implied by the intertemporal consumer choice problem. The relationship between commodity own rates and the real interest rate is derived, and the conditions for equality of commodity own rates are discussed. The intertemporal commodity substitution elasticities are characterised using commodity rates of interest, and the intertemporal substitution elasticity of consumption is derived from its constituent commodity demands. Evidence from estimation of the demand system and the consumption function reveals high intertemporal substitution for consumer goods as well as consumption.     

On the Peaking of Consumption with Exhaustible Resources and Zero Net Investment

We investigate an intertemporal model with an exhaustible resource inflowwhich exhibits a single peak in consumption on the path of development. Thepeak follows the date at which net investment is zero. The ``top' ofconsumption is higher and flatter and peaks later when the discount rate islower. ``Low' endowments of the exhaustible resource stock (and ``high'discount rates) are associated with strictly declining consumption paths.     

Hyperbolic Discounting,Borrowing Aversion and Debt Holding

Analysis of an original Internet‐based survey reveals that debt holding is related to time discounting through: (i) present bias, measured by the degree of declining impatience in the generalized hyperbolic discount function; (ii) borrowing aversion, captured by a sign effect in that future losses are discounted at lower rates than future gains; and (iii) impatience, measured by the overall discount rate. Hyperbolic respondents are classified naïve if their answers reveal them to be time‐inconsistent procrastinators, and otherwise sophisticated. Naïve respondents with more steeply declining impatience are more likely to be debtors. The sign effect relates negatively to borrowing. Survey responses indicative of high or declining impatience are associated with credit card borrowing and other overborrowing indicators.     

Empirical and public choice evidence for hyperbolic social discount rates and the implications for intergenerational discounting

The derivation of the correct discount rate for intergenerational projects in Cost Benefit Analysis is particularly contentious. Public choice has resulted in lower discretionary exponential discount rates for many intergenerational projects in Britain and the USA. This is shown to be strong indirect evidence that the true social discount rate may be a hyperbolic (rather than an exponential) function. There is also empirical evidence for this hypothesis. The hyperbolic nature of discounting is also a standard finding in the behavioural sciences. For intergenerational time frames hyperbolic discount rates should be employed together with exponential discount rates in cost-benefit sensitivity analyses.Sincere thanks to Maureen Cropper and Paul Portney for supplying their survey results and to Elaine Barrow and Phillip Judge for graphics assistance. Two anonymous referees also provided valuable comments.     

Estate tax and lifetime income inequality

This paper constructs a heterogeneous, intertemporal general equilibrium framework which integrates both intended and unintended bequest motives to examine the long-run effects of an estate tax on the inequality of lifetime income. The results are ambiguous in general and sensitive to the type of transfer motive involved. We find that in the purely intended bequest case, an estate tax increases the steady-state inequality of net lifetime income in the case where people's elasticity of intertemporal substitution is greater than one. However, in the purely unintended bequest case, the effect of an estate tax on inequality is dependent on the probability of survival.     

Do retirement planning strategies alter the effect of time preference on retirement wealth?

An individual’s willingness to accumulate retirement wealth is influenced by their preference for intertemporal consumption. People with a strong preference for current consumption (high personal discount rate) may choose to save less and face the risk of decreased retirement preparedness. A negative relation between a high personal discount rate and retirement wealth may be reduced when individuals engage in some form of retirement planning. Using the National Longitudinal Survey of Youth, we provide evidence that respondents with a high personal discount rate accumulated 37% less retirement wealth, on average, between 2004 and 2008, when compared with respondents with a low personal discount rate. However, when retirement planning strategies were included in the model, there was no statistical difference in retirement wealth between people with high and low personal discount rates. The retirement planning strategies included calculating a retirement income need, hiring a financial planner for retirement or engaging in both of these activities.     

Intertemporal Valuation of River Restoration

Willingness to pay for an environmental improvement is a function of how long it takes to deliver the improvement. To measure the effect of time on benefits, I utilize a discrete choice experiment that includes an attribute for delay until the improvement occurs and simultaneously estimate discount rates and valuation parameters. I estimate the present value of immediate and delayed Minnesota River Basin improvements using discount rates directly estimated from the econometric model. Compared to an immediate river basin cleanup, Minnesota residents lose almost half of the benefits when cleanup is delayed by 5 years.     

Intertemporal price discrimination and consumer demand

Under a particular class of utility functions, intertemporal price discrimination (IPD) is not feasible. That is, customers cannot be made to pay different prices for a durable good at different points in time. Other factors such as falling costs, and differing discount rates between buyers and sellers have been found to make intertemporal pricing schemes feasible, or even profitable. None of these factors, however, were fundamental demand differences which give rise to static price discriminations. In this paper we argue that IPD is indeed feasible and sometimes profitable, if only we allow for a nondurable good in the utility function. A simple additively separable utility is examined first, which is then extended to a nonseparable utility function which allows richer substitution/complementary relations between the durable and the nondurable goods. This may help us to better understand the similarities between static and intertemporal price discriminations.     

INTERTEMPORAL UTILITY SMOOTHING: THEORY AND APPLICATIONS

This paper reviews models of intertemporal choice designed to be consistent with a phenomenon called a preference for spread; that is, where a decision‐maker prefers to spread good and bad consumption evenly over time. We closely examine the notion of utility smoothing adopted in these models as a source of the preference for spread. The paper also reviews extensions of these models where a strong aversion to volatility involved in a utility sequence causes preferences to be nonmonotone. Furthermore, to gain a better understanding of the behaviour implied by these models, we apply them to the Diamond growth model.     

Intertemporal price discrimination in infinite horizon

In infinite horizon, a credible durable-good monopolist may resort to intertemporal price discrimination. We provide an analytical characterization of his optimal price policy when consumers and the monopolist have different values for the trade because of distinct discount factors.     

On negative time preferences

Survey data show that subjects positively discount both gains and losses but discount gains more heavily than losses. This holds for monetary and non-monetary outcomes. These results do not confirm the findings of two earlier studies about negative time preferences for non-monetary outcomes.     

Intertemporal dynamic choice under myopia for reward and different risk tolerances

This paper discusses the rationality in an intertemporal dynamic choice under human psychological biases through numerical experiments. A decision maker tries to find the optimal choice in a financial problem by maximizing the subjects?? expected utility for multiple periods, which is measured by the value function in the prospect theory. The subjects are assumed to be myopic for monetary reward and show time-inconsistent preference. Additionally, they have different risk tolerances for gains and losses, causing the framing effect. Under these conditions, a comparative analysis is carried out numerically to evaluate a combined effect of the two psychological factors on the intertemporal choice. The paper also presents a simple computational method for the numerical analysis and proves its validity.     

Delegation and firms’ ability to collude

In a model of repeated Cournot competition under complete information, we show that delegation has no effect on cartel stability if managers collude, while it may hinder cartel stability when owners collude in setting the incentive schemes. If owners can choose whether to delegate or keep control of their respective firms, and both groups of individuals collude or play non-cooperatively in their respective variables according to the level of intertemporal discount factor, then if managers are not able to collude in output levels, owners’ delegation decision is non-monotone in the discount factor.     

Income inequality in the trust game

This paper presents an experiment measuring how lab-induced income inequality affects trust and trustworthiness. Low endowment subjects paired with high endowment subjects showed more trust than subjects in other pairs; this trust was reciprocated with high trustworthiness.     

KLEM substitutability: a dynamic flexible demand system

The theory of intertemporal budget constraint is applied to test Italian public debt sustainability, with the finding that current fiscal policy has not been following a sustainable path in the 1980s. In particular, we find that (i) while primary surplus is stationary, public debt is not, (ii) permanent shocks explain about 90% of forecast error variance of public debt, while playing a minor role in primary surplus and (iii) debt is not sustainable even if stochastic discount rates are accounted for.