Dynamic effects of externalities,optimal saving and economic growth

Conclusion Recognizing the fact that provision of mixed public goods can result in both consumption externalities of the Samuelsonian variety as well as production externalities we set out to extend the earlier results of Rao and Kalpagam (1977) on the effect of public goods on economic growth. In so doing, we considered three standard specifications of production externalities and enlarged the concept of consumption displacement. Our basic conclusion is that the results of our earlier paper remain valid under the more general conditions set out in this paper.     

Increasing returns and aggregate production efficiency by a monopoly

This paper considers an economy where there are many firms with increasing-returns-to-scale technologies and attempts to derive sufficient conditions ensuring that monopoly achieves aggregate production efficiency. In a setting of one output and many inputs, we obtain such sufficient conditions which can be interpreted as a nondecreasing generalized average productivity of inputs for each firm. We also show that a special class of generalized Cobb-Douglas production functions has such a property that monopoly always achieves aggregate production efficiency.     

Existence of equilibria for economies with externalities and a measure space of consumers

Summary. This paper considers an exchange economy with a measure space of agents and consumption externalities, which take into account two possible external effects on consumers preferences: dependence upon prices and dependence upon other agents consumption. We first consider a model with a general externality mapping and we then treat the particular case of reference coalition externalities, in which the preferences of each agent a are influenced by prices and by the global or the mean consumption of the agents in finitely many (exogenously given) reference coalitions associated with agent a. Our paper provides existence results of equilibria in both models when consumers have transitive preferences. It extends in exchange economies the standard results by Aumann [2], Schmeidler [16], Hildenbrand [12], and previous results by Greenberg et al. [11] for price dependent preferences, Schmeidler [17] for fixed reference coalitions and Noguchi [15] for a more particular concept of reference coalitions. We also mention related results obtained independently by Balder [4].Received: 25 May 2004, Revised: 19 October 2004, JEL Classification Numbers: D62, D51, H23. Correspondence to: Bernard CornetThis paper has benefited from comments and valuable discussions with Erik Balder, Stefan Balint, Jean-Marc Bonnisseau, Alessandro Citanna, Gael Giraud, Filipe Martins-da-Rocha, Jean-Philippe Médecin, Jean-François Mertens, Nicholas Yannelis and an anonymous referee.     

Consumption externalities: a representative consumer model when agents are heterogeneous

We examine a growth model with consumption externalities where agents differ in their initial capital endowment and their reference group. We show under which conditions the aggregate equilibrium with heterogeneous agents replicates that obtained with a representative consumer, despite the fact that different individuals have different consumption levels. Next we consider the implications of the presence of consumption externalities for the long-run distributions of income and wealth. We find that, in a growing economy, “keeping up with the Joneses” results in less inequality than would prevail in an economy with no consumption externalities.     

Accounting Price of an Exhaustible Resource: Response and Extensions

Wei (Environ Resour Econ 60:579–581, 2015) presents a novel derivation of the accounting price for an exhaustible resource in a non-optimal economy subject to an allocation mechanism. We show that Wei (2015) and Hamilton and Ruta (Environ Resour Econ 42:53–64, 2009) are in fact employing different and mutually exclusive allocation mechanisms for the economy, and this explains the differences between the respective accounting prices. Because accounting prices must be defined subject to the allocation mechanism for the economy, the prices derived in the two papers are equally valid within their respective allocation domains. Further analysis shows that if there is declining marginal product of factors, a ‘Hartwick investment rule’ for the model economy (set investment just equal to depletion, valued at the accounting price) will lead to declining consumption for the Wei (2015) accounting price, and increasing consumption for the Hamilton and Ruta (2009) accounting price. This result is extended to consider the accounting standards recommended in the UN SEEA (System of environmental-economic accounting 2012: central framework. United Nations, European Commission, Food and Agriculture Organization of the United Nations, International Monetary Fund, Organisation for Economic Co-operation and Development, World Bank, 2012), as well as accounting for environmental externalities from resource use.     

An exchange economy can have an empty α-core

Summary Yannelis has shown that under very mild conditions on preferences, a 2-agent exchange economy has a nonempty -core [4, Corollary 4.2]. The purpose of the present paper is to demonstrate that an exchange economy with three or more agents can have an empty -core. Hence, Yannelis' result would not extend to three or more agents. Examples are provided with and without free disposal, and all preferences are described by linear utility functions. These results are compared with those of Scarf [3], who proved the existence of an -core solution for a large class ofn-person games. The comparison is carried out on two levels. First, since Scarf [3] and Yannelis [4] use different definitions for the -core of an exchange economy, we compare these definitions. Second, the present results show that a natural extension of Scarf's theorem forn-person games fails if certain feasibility constraints are incorporated.I am grateful to Nicholas Yannelis, Atsushi Kajii, Stephan Krasa, and an anonymous referee for their comments, and to a second anonymous referee whose suggestion substantially simplified the 3-agent example.     

GROWTH AND BUBBLES WITH CONSUMPTION EXTERNALITIES*

This paper explores the role of consumption externalities in an overlapping generations economy with capital accumulation. If consumers in each generation are concerned with other agents’ consumption behaviours, there exist intergenerational as well as intragenerational consumption externalities. It is the presence of intergenreational consumption externalities that may produce fundamental effects both on equilibrium dynamics and on steady‐state characterization of the economy. This paper demonstrates this fact in the context of a simple model of endogenously growing, overlapping‐generations economy with or without asset bubbles.     

Agent-based modelling of novelty creating behavior and sectoral growth effects—Linking the creative and the destructive side of innovation

For grasping the relationship between novelty creating activities of agents and growth of economic aggregates, a multi-level approach is suggested. The first level specifies the triggering conditions for novelty creating activities for the agents, i.e. firms. Here the behavioral elements and the modes of actions for the firms are portrayed using an agent-based approach (Section?2). On the second level, the consequences of successful innovations and imitations in a given sector of economic activities are dealt with (Section?3). This depends on the frequency of successful novelties and on the way they diffuse in that sector. We use an agent-related functional approach, applying difference equations for depicting the stylized facts of the diffusion dynamics. Only if these different levels of economic dynamics are distinguished as well as related to each other, is it possible to derive aggregate effects of novelties for the whole economy. This will be done by way of computer simulations (Section?4). Conclusions are drawn in Section?5.     

Constitutional interests in the face of innovations: how much do we need to know about risk preferences?

In constitutional political economy, the citizens’ constitutional interests determine the social contract that is binding for the post-constitutional market game. However, following traditional preference subjectivism, it is left open what the constitutional interests are. Using the example of risk attitudes, we argue that this approach is too parsimonious with regard to the behavioral foundations to support a calculus of consent. In face of innovative activities with pecuniary and technological externalities in the post-constitutional phase, the citizens’ constitutional interests vary with their risk preferences. To determine what kind of social contract is generally agreeable, specific assumptions about risk preferences are needed.

The outcome of the Pasinetti process reconsidered: A note

Conclusion By introducing into the Pasinetti model the plausible assumption that workers and capitalists, respectively, maximize their consumption over time, it has been shown, that only with a well-behaved production function may the long-run outcome of the Pasinetti process be considered as an equilibrium position. In all other cases capitalists can increase their steadystate level of consumption without sacrificing any consumption today. As the maximal capitalists' consumption per head is determined by the technical conditions of production, the profit rate isnot independent of those conditions. We have not taken into account all problems of stability of the steady-state paths or the question of utility maximization over time, i. e. optimal saving; the former because the analysis of the transition processes are very difficult, the latter because of the dubious assumptions, which are necessary to get some convenient results.     

Computers And Growth

The purpose of this paper is to describe the impact of investment in computers on the growth of the U.S. economy. The economic literature on computers is relatively rich in information on the decline in computer prices and the growth of computer investment. Constant quality price indices for computers have been included in the U.S. National Income and Product Accounts (NIPA) since 1986. These indices employ state of the art methodology to capture the rapid evolution of computer technology.

While the annual inflation rate for overall investment has been 3.66 percent for the period 1958 to 1992, computer prices have declined by 19.13 percent per year! Similarly, overall investment grew at 3.82 percent, while investment in computers increased at an astounding 44.34 percent! These familiar facts describe growth in the output of computers. The objective of this paper is to complete the picture by analyzing the growth of computer services as inputs.

In a pioneering paper Bresnahan (1986) has focused on pecuniary externalities arising from the rapid decline in computer prices. Griliches (1992, 1994) has emphasized the distinction between pecuniary and nonpecuniary externalities in the impact of computer investment on growth. This paper is limited to pecuniary externalities or the impact of reductions in computer prices on the substitution of computer services for other inputs. As Griliches (1992) points out, this is an essential first step in identifying nonpecuniary externalities or ‘spill-overs’ through the impact of a decline in computer prices on productivity growth. ^{* *}Brynjolfsson (1993) has proveded a detailed survey of studies of nonpecuniary externalities or ‘spill overs’. Recent studies include those of Brynjolfsson and Hitt (1994a, 1994b) and Lichtenberg (1993).

In two important papers Stephen D. Oliner (1993, 1994) has introduced a model of computer technology that greatly facilitates the measurement of computer services as inputs. In this paper we estimate computer stocks and flows of computer services for all forms of computer investment included in NIPA. We construct estimates of computer services parallel to NIPA data on computer investment by combining these data with information on computer inventories. For example, the International Data Corporation (IDC) Census of Computer Processors includes an annual inventory of processors in the U.S.

In Section 1 we present data on investment in computers and constant quality price indices from NIPA. These data incorporate important innovations in modeling computer technology stemming from a joint study by IBM and the Bureau of Economic Analysis (BEA) completed in 1985. This study utilized a ‘hedonic’ methodology for constructing an econometric model of computer prices that accurately reflects rapid changes in computer technology. This methodology generates an index of computer prices that holds the quality of computers constant.

In Section 2 we present the model of computer services originated by Oliner (1993,1994). This differs in important respects from the model of capital services used in the previous studies of U.S. economic growth surveyed by Jorgenson (1989,1990). The model employed in previous studies is based on the decline in productive capacity with the chronological age of a capital good. Oliner assumes that computers maintain their productive capacity until they are retired. Decline in productive capacity occurs only through removal of used computers from the inventory through retirement.

In Section 3 we construct estimates of stocks of computers that incorporate IDC data on computer inventories and derive the implied flow of computer services. While output of computer investments has grown very rapidly, the input of computer services has grown even faster. The price of these services has declined at 23.22 percent per year over the period 1958 to 1992, while the input of these services has grown at 52.82 percent! This is prima facie evidence of an important role for computer price declines as a source of pecuniary externalities.

In Section 4 we combine computer services with the services of other types of capital to produce a measure of capital input into the U.S. economy. We link this with labor input to obtain the contributions of both inputs to U.S. economic growth, arriving at the growth of productivity as a residual. We find that the contribution of computer services to input into the U.S. economy is far more important than the contribution of computer investments to output. This is a significant step toward resolution of the Solow paradox: ‘We see computers everywhere except in the productivity statistics. ^{* *}Robert M. Solow, quoted by Brynjolfsson (1993). Declines in computer prices generate very sizable pecuniary externalities through the substitution of computer services for other inputs. By contrast Solow focuses on nonpecuniary externalities that would appear as productivity growth.

In Section 5 we conclude that information on inventories of computers is critical in quantifying the role of computer services as inputs. The constant quality price indices for computers incorporated into NIPA are also essential. A price index for computers that reflects only general trends in inflation would result in a highly distorted perspective on the growth of GDP and capital services, especially during the past decade. To capture the contribution of all forms of investment to U.S. economic growth, similar price indices should be included in NIPA for capital goods with rapidly evolving technologies, as proposed by Gordon (1990).

The long term goal should be a unified system of income. product, and wealth accounts, like that proposed by Laurits Christensen and Jorgenson (1973) and Jorgenson (1980). This incorporates capital stocks, capital services, and their prices. Achieving this goal will necessitate much greater elaboration of the accounting system described in Section 3. These accounts would incorporate data on prices and quantities of investment, stocks of assets, and capital services for all forms of capital employed in the U.S. economy.     

Indeterminacy in a small open economy with endogenous labor supply

Summary. We establish conditions under which indeterminacy can occur in a small open economy business cycle model with endogenous labor supply. Indeterminacy requires small externalities in technologies with social constant returns to scale, independently of the intertemporal elasticities in both consumption and labor. Received: December 12, 2001; revised version: May 17, 2002 RID="*" ID="*"The paper has benefited from discussions with Jess Benhabib and Mark Weder, as well as from the comments of an anonymous referee. Correspondence to: Q. Meng     

Externalities, consumption constraints and regular economies

We consider a general model of pure exchange economies with consumption externalities. Households may have different consumption sets and each consumption set is described by a function called the possibility function. Utility and possibility functions depend on the consumptions of all households. Showing by means of an example that basic assumptions are not enough to guarantee generic regularity, we provide sufficient conditions for generic regularity in the space of endowments and possibility functions.     

Efficient Management of Product Durability and Recyclability under Utilitarian and Chichilnisky Preferences

In a dynamic general equilibrium vintage model we explicitly consider the relationship between the product attributes durability and recyclability. Efficient management in the case that green design markets fail is analyzed both under Utilitarian and Chichilnisky preferences. It turns out (a) that durability may be inefficient even in a perfectly competitive economy in which environmental externalities are absent, (b) that the efficiency-restoring tax-subsidy schemes crucially depend on the kind of preferences, and (c) that changing the property rights for consumption goods and residuals is a promising policy option to overcome market failure independent of the kind of preferences.     

Robust ergodic chaos in discounted dynamic optimization models

Summary We identify a family of discounted dynamic optimization problems in which the immediate return function depends on current consumption, capital input and a taste parameter. The usual monotonicity and concavity assumptions on the return functions and the aggregative production function are verified. It is shown that the optimal transition functions are represented by the quadratic family, well-studied in the literature on chaotic dynamical systems. Hence, Jakobson's theorem can be used to throw light on the issues of robustness of ergodic chaos and sensitive dependence on initial conditions.     

Learning from private and public observations of othersʼ actions

We study the diffusion of dispersed private information in a large economy, where agents learn from the actions of others through two channels: a public channel, such as equilibrium market prices, and a private channel, for example local interactions. We show that, when agents learn only from the public channel, an initial release of public information increases agents? total knowledge at all times and increases welfare. When a private learning channel is present, this result is reversed: more initial public information reduces agents asymptotic knowledge by an amount in order of $\log (t)$ units of precision. When agents are sufficiently patient, this reduces welfare.     

On characterizing equilibria of economies with externalities and taxes as solutions to optimization problems

Summary We characterize equilibria of general equilibrium models with externalities and taxes as solutions to optimization problems. This characterization is similar to Negishi's characterization of equilibria of economies without externalities or taxes as solutions to social planning problems. It is often useful for computing equilibria or deriving their properties. Frequently, however, finding the optimization problem that a particular equilibrium solves is difficult. This is especially true in economies with multiple equilibria. In a dynamic economy with externalities or taxes there may be a robust continuum of equilibria even if there is a representative consumer. This indeterminacy of equilibria is closely related to that in overlapping generations economies.An earlier version of this paper, entitled Externalities and Taxes in General Equilibrium, was presented at the North American meetings of the Econometric Society, June 1988, at the University of Minnesota. We are grateful to David Backus, Kenneth Judd, Patrick Kehoe, and Rodolfo Manuelli for helpful conversations. National Science Foundation grants SES 86-18325 and SES 87-08616 provided financial support.The views expressed herein are those of the authors and not necessarily those of the Federal Reserve Bank of Minneapolis or the Federal Reserve System.     

Evolution of market shares with repeated purchases and heterogeneous network externalities

We investigate how market shares change when a new, superior technology exhibiting network externalities is introduced in a market initially dominated by an old technology. This is done under the assumption that consumers are heterogeneous in their valuation of technology quality and network externalities and that goods are not (perfectly) durable and thus have to be bought repeatedly. When both technologies are unsponsored, the old technology dominates when the quality difference is small, and it disappears when the quality difference is large. When the new technology is sponsored, the relationship between the quality difference and the long-run market share of the new technology is non-monotonic and the old technology always continues to exist.

Indeterminacy in dynamic models: When Diamond meets Ramsey

We consider an aggregate two-periods overlapping generations model with endogenous labor, consumption in both periods of life, homothetic preferences and productive external effects coming from the average capital and labor. We show that under realistic calibrations of the parameters, in particular a large enough share of first period consumption over the wage income, local indeterminacy of equilibria cannot occur with capital externalities alone. It can nevertheless occur when there are only, even very small, vanishing labor externalities provided that the elasticity of capital-labor substitution and the wage elasticity of the labor supply are large enough. We also show that if labor externalities are slightly stronger, but still small enough to be plausible, and the elasticity of labor supply is larger, local indeterminacy occurs in a Cobb-Douglas economy. Finally, we show that a locally indeterminate steady state is generically characterized by an under-accumulation of capital. It follows therefore that while agents live over a finite number of periods, the conditions for the existence of locally indeterminate equilibria are very similar to those obtained within infinite horizon models and that from this point of view, Diamond meets Ramsey.     

Optimal dynamic environmental policies of a profit maximizing firm

In this paper we study the optimal environmental policy of the firm for different scenarios dependent on (costs of) production technologies, financing costs, and governmental policy. The governmental instruments to be considered are: