Variety‐Controlling Public Policy Under Addiction and Saturation

This paper constructs a tractable general equilibrium model for investigating the dissimilar effects of addiction and saturation on consumption and public policy. By introducing an industry‐specific intertemporal consumption externality, we provide clear analytical results that a lump‐sum subsidy for firms can increase welfare in the presence of a negative externality (saturation). A tax can accomplish the same given a positive externality (addiction). Unlike existing studies of cultural goods, these results are not based on assumptions concerning exogenous different preferences across groups, but rather on conventional monopolistic competition and consumption habit formation models in macroeconomics.     

Intertemporal substitution and random changes in preferences: Time series evidence for four countries

This study attempts to estimate a model of intertemporal substitution taking into account serially correlated changes in preferences with quarterly aggregate time series data for the USA, Great Britain, West Germany and Switzerland. Thereby, necessary optimality conditions representing the trade-offs between present and future consumption, present and future leisure, as well as present consumption and leisure are estimated using the forward-filtered estimator of Hayashi and Sims. The estimation results obtained for the dynamic optimality conditions reject the model formulated. The analysis of the static optimality conditions gave more satisfactory results with respect to intertemporal substitution elasticity in consumption.     

Is there a daily discount rate? Evidence from the food stamp nutrition cycle

Quasi-hyperbolic discounting predicts impatience over short-run tradeoffs. I present a direct non-laboratory test of this implication using data on the nutritional intake of food stamp recipients. Caloric intake declines by 10 to 15 percent over the food stamp month, implying a significant preference for immediate consumption. These findings constitute a rejection of the permanent income hypothesis and are extremely difficult to reconcile with exponential discounting. The data support an explanation based on time preference and reject several alternative explanations, including highly elastic intertemporal substitution. I explore implications for the optimal timing of transfer payments under alternative assumptions about preferences.     

Consumer preferences,the demand for Divisia money,and the welfare costs of inflation

This paper uses neoclassical demand theory to calculate the welfare costs of inflation. It considers the demand interactions between money, consumption goods, and leisure, relaxes the assumption of fixed consumer preferences, and addresses the inter-related problems of estimation of money demand functions, instability of money demand relations, and monetary aggregation. It makes full use of the relevant economic theory and econometrics and generates inference in terms of long-run welfare costs of inflation that is internally consistent with the data and models used.     

Towards a more general approach to testing the time additivity hypothesis

A new procedure is proposed for re-examining the assumption of additivity of preferences over time which, although untenable, is usually maintained in intertemporal analyses of consumption and labour supply. The method is an extension of a famous work by Browning. However, it is more general in permitting the estimation of intertemporal demand systems, which are explicit in an unobservable variable (price of utility), but may lack a closed form representation in terms of observable variables such as prices and total outlay. It also makes extensive use of duality theory to solve the endogeneity problem encountered in Browning's study. Applying this method with an appropriate estimator to the Australian aggregate data, it is found that the time additivity hypothesis is decisively rejected, which is consistent with Browning's conclusion.     

Intertemporal substitution in import demand and the role of habit formation: an application of Euler equation approach for Pakistan

Introduction

The study examines the importance of intertemporal substitution in import demand considering the role of habit formation. A two-goods version of the permanent income model is used in which time-non-separability in consumers’s preferences is assumed. The model is estimated using annual data for Pakistan at disaggregated level covering the period from 1977 to 2017.

Objectives

The objective of the study is to estimate elasticities of substitution along with parameters of habit formation for consumption goods at a disaggregated level.

Method

The study employs co-integration for the estimation of parameters of elasticities of substitution and generalized method of moments (GMM) for the estimation of the parameters of habit formation from Euler equations.

Findings

The estimates of intertempral elasticity of substitution suggest that the nature of commodity group (necessity/luxury) plays an important role when consumers are making intertemporal choices. Moreover, the study finds that intratemporal elasticity of substitution is larger than intertempral elasticity of substitution in almost all cases in Pakistan, suggesting that imported and domestic goods are best described as substitutes in Edgeworth-Pareto sense. In addition, the inclusion of habit formation delivers results with plausible signs and the habit formation process seems significant for certain commodity groups including tea, beverages, tobacco products and drugs.

Conclusion

The study concludes that there is a possibility of crowding out effect on domestic consumption and the depreciation of local currency may improve Pakistan’s balance of trade.

     

The Long-Run Effect of a Tax-Rebate Program

In each period of a dynamic tax-rebate program, a (fixed) quantity tax is imposed on each unit of a given good, and the tax revenue is rebated back to the consumer in the next period. The program lasts for infinite number of periods. The author considers a representative consumer's dynamic consumption behavior, the long-run steady-state consumption, and the consumer's welfare. Under the standard continuity and strict convexity assumptions on the consumer's preferences, he shows that the tax strictly reduces the consumption of the good in each period as well as in the steady state, and the consumer is strictly worse off. He also provides numerical analysis when the consumer has the quasilinear or the Cobb-Douglas utility functions.     

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.     

Climate policy targets in emerging and industrialized economies: the influence of technological differences, environmental preferences and propensity to save

Although emerging economies claim that industrialized countries need to reduce their carbon emissions first, stabilization of the future global climate system requires immediate action by all countries. In a stylized two-country intertemporal general equilibrium model, we derive welfare maximizing emission caps in emerging and industrialized countries, taking account of country differences in technology, environmental preferences and propensity to save. Simultaneous target setting is compared to a sequential one in which the industrialized country commits itself to binding targets first. In the latter case, when the industrialized economy has stronger environmental preferences and a lower relative pollution production share, the industrialized economy can increase its joint economic and environmental welfare by setting a laxer target. On the other hand, when the emerging economy has considerably higher environmental preferences, our results suggest that the industrialized economy will choose a more restrictive target in a sequential setting than in a simultaneous one, contrary to first thought that a first mover is always pursuing a ‘symbolic’ policy with a lax target.     

What explains consumption in the very short-run? Evidence from checking account data

This paper investigates consumption behavior within an intertemporal optimization model of the representative household. Our dataset consists of deposits and withdrawals from individual household checking accounts that received paychecks by direct deposit. We construct samples of panel data for households with weekly, biweekly, and semi-monthly pay-periods and form two different measures of consumption for each sample. GMM estimates of structural parameters provide mixed evidence for habit formation or durability and limited support for the permanent income hypothesis. The results instead point to “rule of thumb” consumption under liquidity constraints, where the household consumes its current disposable income each pay-period with possible debt servicing. These findings are uniform with regard to estimation of sub-samples split according to age or household income.     

The social cost of living index

Household cost of living indexes reflect household preferences; analogous indexes for groups of households require a corresponding concept of group preferences. In this paper I investigate the ‘social cost of living index’, a group index based on the Bergson-Samuelson social welfare function. I first define the index and examine its properties under the assumption that the investigator constructing it expresses his distributional judgments in an explicit Bergson- Samuelson social welfare function; I then examine the ‘maximizing society’ and the ‘independent society’, two cases in which the index can be constructed from the information contained in the market demand functions. In these two cases a Laspeyres index (i.e. the fixed weight index based on the reference consumption pattern) is an upper bound on the exact social cost of living index. In general, however, the assumptions required to place bounds on the social cost of living index are much more likely to be satisfied than those required to place analogous bounds on a household's cost of living index.     

Empirical demand systems incorporating intertemporal consumption dynamics

This article presents and estimates demand systems by explicitly incorporating intertemporal consumption behavior as summarized by the Euler equation. Demand systems are characterized by two indirect utility functions which are effectively globally regular and can better approximate nonlinear Engel curves. Furthermore, an exact and nonlinear Euler equation is derived without a log approximation. This equation is estimated jointly with the demand functions by a careful implementation of the orthogonality conditions using generalized method of moments. We illustrate the techniques by estimating the demand system and Euler equation for Australian aggregate data. Results generally indicate that the proposed methods are promising. The estimated rate of time preference is fairly small while the restrictions producing the moment equations are not rejected. Estimated Frisch price elasticities, which are relevant in an intertemporal setting, appear reasonable, and the intertemporal elasticity of substitution for consumption is found to be small, which are consistent with the findings in earlier studies.     

The dynamic effects of tax policies in a small open economy

We develop an intertemporal optimizing model of a small open economy with both durable and nondurable consumption to address the implications of alternative tax policies. An increase in lump sum taxes reduces the steady state level of consumption and improves the stock of foreign bonds. Consistent with empirical evidence, durable consumption exhibits initial excess volatility. Though an increase in the tax on durables increases the demand for nondurables and improves the bond holdings in the steady state, an increase in the tax on nondurables has insignificant effects on the stock of foreign bonds and the consumption of durables. Using quarterly data from the UK and estimating generalized impulse response functions we find empirical support. We also calibrate the welfare implications of different tax policies.     

Expectations and intertemporal separability in an empirical model of consumption and investment under uncertainty

An intertemporal model of consumption and investment under uncertainty is formulated, and compared with the existing literature; it is argued that an assumption of myopia is necessary for its empirical applicability. It is estimated by maximum likelihood with quarterly British data. A specification search for a satisfactory form of expectations is made, and the estimated model is compared with a static demand system. Strong intertemporal separability is formulated as a nested hypothesis, and strongly rejected by a likelihood ratio test.     

Present bias and the inefficiency of the centralized economy: The role of the elasticity of intertemporal substitution

We analyze an endogenous growth model considering agents with an isoelastic utility. Preferences are characterized by a utility affected by a negative externality, and a level of impatience which decays with the time distance from the present. Agents who cannot commit the actions of their future selves, play a game against them. The stationary equilibrium of this game defines a balanced growth path with a slower growth when played by subsequent central planners than when played by decision makers in the market economy. First, we prove that the fast growing market economy implies higher welfare if the negative externality is small, while the centralized economy is welfare improving above a given threshold for the externality (obtained for a specific family of non-constant discount functions). Secondly, we observe that this threshold increases with the elasticity of intertemporal substitution in consumption. Therefore, the greater this elasticity the more likely it is that the externality lies below this threshold, where policy interventions would not be adequate. Finally, as one would expect, the range of values of the externality for which the market equilibrium provides higher welfare widens the more different from constant discounting time preferences are, due either to a wider range of variation for the instantaneous discount rates or because these decay more slowly.     

Estimating the elasticity of intertemporal substitution taking into account the precautionary savings motive

This paper estimates the elasticity of intertemporal substitution for U.S. aggregate time series data, taking into account the precautionary savings motive. By making use of a recursive utility function, we estimate an Euler equation, via GMM. This procedure leads consumption growth rate to depend on asset returns, and on a time-varying variance, which captures the precautionary motive. When significant, the elasticity of intertemporal substitution estimates ranges from 0.4 to 1.8, which are higher than most of the results found in the literature. Furthermore, the evidence suggests that consumers react to risk; however, the contribution of precautionary motive to consumption growth seems to be limited.     

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.     

Time-inconsistent preferences in a general equilibrium model

This paper introduces time-inconsistent preferences in a multicommodity general equilibrium framework with incomplete markets. The standard concept of competitive equilibrium is extended in order to allow for changes in intertemporal preferences. Depending on whether or not agents recognize that their intertemporal preferences change, agents are called sophisticated or naïve. This paper presents competitive equilibrium notions for economies with naïve agents and economies with sophisticated agents and provides assumptions under which both types of equilibria exist. Surprisingly, the set of naïve equilibria in societies populated by time-consistent households is not allocationally equivalent to the set of competitive equilibria. For sophisticated equilibria, the equivalence holds. Time-inconsistency also raises conceptual issues about the appropriate concept of efficiency. Choices have to be made concerning the incorporation of future preferences and the appropriate instruments to create Pareto improvements. For both naïve and sophisticated societies, we present four possible efficiency concepts. Suitable conditions are specified for which both naïve and sophisticated equilibria satisfy appropriate efficiency concepts.     

ESTIMATING TEMPTATION AND COMMITMENT OVER THE LIFE CYCLE

This article estimates the importance of temptation for consumption smoothing and asset accumulation in a life‐cycle model. We use two complementary estimation strategies: first, we estimate the model‐implied Euler equation; second, we match liquid and illiquid wealth accumulation using the method of simulated moments. In both cases, we find that the utility cost of temptation is one‐quarter of the utility benefit of consumption. Further, temptation is crucial for correctly estimating the elasticity of intertemporal substitution (EIS): EIS estimates are biased downward when ignoring temptation. Finally, the model only matches the share of illiquid wealth if temptation is in the preference specification.     

Indeterminacy and multiple steady states with sector-specific externalities

This paper studies a two-sector model with aggregate and sector-specific external effects in production and inelastic labor supply. We first characterize the existence, uniqueness and multiplicity of the steady states as well as their welfare properties. We particularly focus on the CES production functions and show that the steady state is generically either unique or there are exactly two. A simple geometrical methodology enables us to characterize the local dynamics of the steady state. We show that in order to get indeterminacy, the presence of both aggregate and sector-specific external effects is needed, along with low capital–labor elasticities of substitution and high, but bounded from above, elasticities in intertemporal consumption. We perform a sensitivity analysis and show that indeterminacy emerges for parameter values in line with those used in calibrations of standard RBC models, that is for unitary elasticities of input substitution and of intertemporal substitution in consumption.