Environment,Directed Technical Change and Economic Policy

We study the effects of an economic policy in an endogenous growth general equilibrium framework where production of consumption goods requires two resource inputs: a polluting non-renewable resource and a non-polluting labour resource. The use of the former contributes to the accumulation of pollution in the atmosphere, which affects welfare. There is a specific research sector associated with each of those resources. We provide a full welfare analysis, and we describe the equilibrium paths in a decentralized economy. We go on to study the effects of three associated economic policy tools: a tax on the polluting resource, and two research subsidies. We show that the optimal environmental policy has two main effects; it delays the extraction of the resource and with it the level of polluting emissions and it reallocates research efforts, decreasing the amount put into “grey” research to the benefit of “green” research. We also show that the environmental policy is grey-biased in the short-term, and green-biased in the long-term. Finally, we compute the optimal values for these tools.      

Trade and Indeterminacy in a Dynamic General Equilibrium Model

This paper introduces sector-specific externalities in the Heckscher-Ohlin two-country dynamic general equilibrium model to show that indeterminacy of the equilibrium path in the world market can occur. Under certain conditions in terms of factor intensities, there are multiple equilibrium paths from the same initial distribution of capital in the world market, and the distribution of capital in the limit differs among equilibrium paths. One equilibrium path converges to a long-run equilibrium in which the international ranking of factor endowment ratios differs from the initial ranking; another equilibrium path maintains the initial ranking and converges to another long-run equilibrium. Since the path realized is indeterminate, so is the long-run trade pattern. Therefore, the Long-Run Heckscher-Ohlin prediction is vulnerable to the introduction of externality. Journal of Economic Literature Classification Numbers: E13, E32, F11, F43.     

Policy Rules and Monetarist Arithmetic

This note demonstrates the existence of an important equilibrium path overlooked in the literature on monetarist arithmetic. Pleasant monetarist arithmetic is possible when the interest‐elasticity of money demand exceeds unity. In this case, tight money may lead to a transitory increase in seigniorage, the retirement of government debt, and lower inflation in both the short run and the long run. The set of equilibrium paths is sensitive, however, to the form of the policy rule. Pleasant monetarist arithmetic is not an equilibrium if the policy rule fixes the share of the fiscal deficit financed by seigniorage. Both pleasant monetarist arithmetic and the tight‐money paradox are equilibrium paths when the government's commitment to low money growth is conditional on inflation remaining below its previous level.     

Candidate strategies in primaries and general elections with candidates of heterogeneous quality

I consider a model in which candidates of differing quality must win a primary election to compete in the general election. I show that there is an equilibrium in which Democrats choose liberal policies and Republicans choose conservative policies, but higher quality candidates choose more moderate policies than lower quality candidates. In this equilibrium, higher quality candidates choose more moderate policies if they have a larger quality advantage or there is less uncertainty about the median voterʼs ideal point in the general election, and the candidates in a given primary choose closer policies to one another when there is a smaller quality difference between the candidates in a primary. I further show that if the candidates have policy motivations, then a low quality candidate may strategically choose to enter a primary even if running for office is costly and the candidate will lose the primary election with certainty in equilibrium.     

Indeterminate Balanced Growth under Habit Persistence and Fiscal Policies

This paper studies a dynamic general equilibrium model with habit persistence in preferences and fiscal policies of taxation and expenditures. Preference takes a subtractive form of habits (the marginal rate of substitution between the agent's own consumption and habit stocks is constant), and technology is linear in aggregate capital (the economy grows without a limit in the long run). We find a continuum of competitive equilibrium paths in conjunction with a unique balanced growth path in the growing economy, in which habits represent both envy/jealousy and altruism/admiration. In addition, in the social optimum under second-best fiscal policies, we show the existence of indeterminacy in transitional allocations along with a unique balanced growth path. Thus, we find that the introduction of habits influences the patterns of the transitional paths but has no impact on the balanced growth path in either competitive or social optimum allocations. The second-best fiscal policy, therefore, restores the socially optimal balanced growth rate but fails to select the unique transitional path among multiple competitive equilibrium paths in the imperfectly competitive economy.     

Aggregate savings when individual income varies

This paper examines aggregate savings in a general equilibrium model where infinitely lived households face volatile (and possibly uncertain) income paths, hold a risk-free asset, and face a borrowing constraint. I first show that the equilibrium capital stock in an economy without uncertainty, but where individual income varies, can be larger than in an economy where each household's income is constant. When individual income is stochastic and uninsurable, the equilibrium capital stock is always larger than when income is constant. This additional capital accumulation has sometimes been interpreted as precautionary savings, but I argue that much of the additional savings are generated by permanent-income motives in combination with strict borrowing constraints.     

Optimality and Natural Selection in Markets

We ask if natural selection in markets favors profit-maximizing firms and, if so, is there a difference between the predictions of models which assume all firms are profit maximizers and the predictions of models which explicitly take account of population dynamics in the market. We show that market selection favors profit maximizing firms, but we also show that the long-run behavior of evolutionary market models is nonetheless not consistent with equilibrium models based on the profit-maximization hypothesis. Dynamic equilibrium paths with market selection are not Pareto optimal, nor even asymptotically optimal. The discrepancy arises because the dynamics created by firm evolution causes prices to vary over time and the resulting dynamical system need not have stable steady states.     

Ramsey fiscal policy and endogenous growth

This paper examines the effects of fiscal policies on capital accumulation and economic performance in a simple endogenous growth model with elastic labor supply by focusing on the implementability of a competitive equilibrium with productive public spending and distortionary taxation. Given a feasible exogenous fiscal policy, productive public spending can, at first, lead to positive short-run and long-run growth in the unique competitive equilibrium. However, although strictly positive growth is possible in the short run, a Ramsey policy with productive public spending does not implement positive capital accumulation in the long run. Also, the local indeterminacy of Ramsey allocations, in conjunction with the global multiplicity, arises as an implementable competitive equilibrium with Ramsey policies: namely, a continuum of transitional dynamics and multiple balanced growth paths. I am grateful to Kazuo Nishimura, Theodore Palivos, Sang Hee Won, John Conlon, Apostolis Philippopoulos, Arved Ashby, In Ho Lee, Katsuaki Terasawa, and an anonymous referee of this journal for valuable comments and suggestions. I also thank seminar participants at Ioannina University, Kyoto University, University of Mississippi, and Seoul National University. This paper is supported by 2006 Sabbatical Project, Kyung Hee University.     

Markov rational expectations equilibria in an overlapping generations model

In this paper, we analyze rational expectations equilibrium paths in a stochastic overlapping generations model. The work presented here builds on results of S. E. Spear (J. Econ. Theory 35 (1985), 251–275), where is is shown that in a model with multiple goods and time non-separable preferences, a stochastic steady state equilibrium will generically fail to exist. A stochastic steady state is defined as an equilibrium in which the stochastic process of endogenously determined variables is measure isomorphic to the exogenous process driving the model. In this paper, we establish the existence of non-steady state equilibria and provide a characterization of their stochastic properties.     

A Sufficient Condition for Topological Chaos with an Application to a Model of Endogenous Growth

This paper provides an easily verifiable sufficient condition for topological chaos for unimodal maps which can be satisfied when the well-known Li–Yorke condition is not satisfied. It then shows how this result can be applied to a model of endogenous growth with externalities to establish the existence of chaotic equilibrium growth paths in that framework. Journal of Economic Literature Classification Numbers: C61, D90, O41.     

Intersectoral Externalities and Indeterminacy

We consider a two-sector economy with positive intersectoral external effects and nonincreasing social returns. We show that if the discount factor ρ is close to 1 then local indeterminacy may be obtained with mild market imperfections. Moreover, with additional conditions, when ρ is made smaller the steady state becomes totally unstable and quasi-periodic cycles, along which equilibrium paths are indeterminate, may appear through a Hopf bifurcation. This will be proved even if the investment good is capital intensive at the private level while this condition guarantees local determinacy in the sector specific case. Journal of Economic Literature Classification Numbers: C62, E32, O41.     

International Trade and the Environment: Theoretical and Policy Linkages

I review and extend three approaches to trade and environmental policies: competitive general equilibrium, oligopoly and monopolistic competition. The first two have surprisingly similar implications: deviations from first-best rules are justified only by constraints on policy choice (which motivates what I call a “single dividend” approach to environmental policy), and taxes and emissions standards differ in ways which reflect the Le Chatelier principle. I also show how environmental taxes may lead to a catastrophic relocation of industry in the presence of agglomeration effects, although not necessarily if there is a continuum of industries which differ in pollution intensity. *An earlier version was presented as an invited plenary lecture to the European Association for Environmental and Resource Economics Conference, Oslo, 1999.     

The determinacy of equilibrium in economies of overlapping generations

We study the problem of uniqueness of equilibrium paths in the overlapping generations model. We show that, despite local calculation based on counting equations and unknowns, the equilibrium path may be unique. We do this by constucting an example of an economy of overlapping generations with just one equilibrium up to time shift, beside the steady states. Time is either discrete or continuous; in either case, it extend into the infinite future and, possibly, the infinite past. There is one, non-storable commodity at each date. The economy is stationary; intertemporal preferences are logarithmic; the endowments and discount factors of individuals need not depend continuously on time. With continuous time, equilibrium paths of prices are smooth; this, even for endowments and discount factors of individuals that do not depend continuously on time. With discrete time, as the number of periods in the life-span of individuals increases, equilibrium paths converge to the continuous time solutions. If time extends infinitely into the infinite past as well as into the infinite future, in continuous time, all non-stationary equilibrium paths of prices are time-shifts of a single path; in addition, there are two stationary solutions; in discrete time, there is a one dimensional family of non-stationary solutions, up to time-shift; however, the indeterminacy vanishes as the number of periods in the life span of individuals tends to infinity. If, alternatively, time has a finite starting point, in discrete time the degree of indeterminacy increases with the life-span of individuals, and, in continuous time, it is infinite; however, these are families of exponentially decreasing oscillations which, although they may exhibit pseudo-chaotic behaviour for a while, as time tends to infinity they all get damped, and asymptotic behaviour is that of the economy that originates in the infinite past. Stefano Lovo made interesting comments.     

A model of political parties

This paper presents a new model of political parties. I assume that the role of parties is to increase the commitment ability of politicians vis-à-vis the voters. Whereas a politician running alone can only offer his ideal policy, the set of policies that a party can commit to is the Pareto set of its members. I show that the commitment mechanisms provided by the institution of parties has no effect when the policy space is unidimensional; the policies parties can induce in equilibrium arise also when politicians are running independently. However, when the policy space is multidimensional, politicians use the vehicle of parties to offer equilibrium policies that they cannot offer in their absence.     

Out of Equilibrium

This review article takes the volume by Mario Amendola and Jean-Luc Gaffard Out of Equilibrium as the starting point of a general assessment of the scope and perspectives of out-of-equilibrium economics. After describing the particular subject-matter covered by Amendola and Gaffard, the author calls attention upon he fundamental role in their treatment of time, coordination, and the magnitude of responses. The general foundations of the ‘out-of-equilibrium’ approach are then considered. In this connection, the author argues that making use of illustrations (rather than formal proofs) can still show in a conclusive way that widely held beliefs are not valid as general propositions. It is also maintained that, apart from these ‘anti-general’ results, the out-of-equilibrium approach can lead to positive generalizations of considerable power and significance. In conclusion, this essay maintains that coexistence of equilibrium and out-of-equilibrium analysis is possible, and mentions research and policy areas (such as coordination failures and rational regulatory policy) in which equilibrium theory can provide invaluable insights for an out-of-equilibrium investigation     

Estimating an equilibrium exchange rate for the dollar and other key currencies

In this paper, we adapt the concept of fundamental equilibrium exchange rates ‘FEER’ in a complete model approach. We use it to determine the likely paths of the Dollar and other key currencies. The FEER is the (real) exchange rate that is consistent with internal balance and sustainable external balances. Here we examine the composition of a Dollar adjustment and hence the extent to which a FEER (for the US) depends on factors or rigidities elsewhere in the world, as well as at home. We find, the US still needs to accept an adjustment in her real exchange rate if the increase in her foreign liabilities is to come to an end. However, counterpart adjustments also have to be made in Canada, Mexico, and some Asian economies if this policy is to be successful. We also show that productivity growth differentials may act as a substitute for depreciation, and this provides an explanation for the failure of the dollar to depreciate in the 1990s.     

Lobbying,political competition and the welfare effect of campaign contribution tax

This paper develops a probabilistic voting model in which a single lobby group commits campaign contributions to parties, contingent on the policy position the party adopts. Parties may have different propensities for diverting campaign funds towards rents. We show that a party that skims more from contributions mobilises fewer uninformed voters but places more value on receiving greater contributions. Further, the contributions and vote share of the party increases with the distance between the lobby's preferred policy and the median voter's ideal policy. Finally, we show that the equilibrium policy is between the median voter's ideal point and the lobby's preferred policy. Such an equilibrium policy does not maximise the aggregate social welfare due to the distortionary nature of lobbying. However, when an appropriate contribution tax is introduced to limit this distortion, social welfare will be maximised.     

A unified approach to comparative statics puzzles in experiments

The paper shows that several game-theoretic solution concepts provide similar comparative statics predictions over a wide class of games. I start from the observation that, in many experiments, behavior is affected by parameter shifts that leave the Nash equilibrium unchanged. I explain the direction of change with a heuristic structural approach, using properties such as strategic complementarities and increasing differences. I show that the approach is consistent with general comparative statics results for (i) the Nash equilibrium of a game with perturbed payoff functions, (ii) the quantal response equilibrium, (iii) level-k reasoning. I also relate the structural approach to equilibrium selection concepts.     

Regional debt in monetary unions: Is it inflationary?

This paper studies the inflationary implications of interest bearing regional debt in a monetary union. Is this debt simply backed by future taxation with no inflationary consequences? Or will the circulation of region debt induce monetization by a central bank?We argue here that both outcomes can arise in equilibrium. In the model economy, there are multiple equilibria which reflect the perceptions of agents regarding the manner in which the debt obligations will be met. In one equilibrium, termed Ricardian, the future obligations are met with taxation by a regional government while in the other, termed Monetization, the central bank is induced to print money to finance the region's obligations. The multiplicity of equilibria reflects a commitment problem of the central bank. A key indicator of the selected equilibrium is the distribution of regional debt holdings. We show that regional governments, anticipating central bank financing of their debt obligations, have an incentive to create excessively large deficits. We use the model to assess the impact of some policy measures within a monetary union as well as dollarization.     

Government policy and the probability of coordination failures

This paper introduces an approach to the study of optimal government policy in economies characterized by a coordination problem and multiple equilibria. Such models are often criticized as not being useful for policy analysis because they fail to assign a unique prediction to each possible policy choice. We employ a selection mechanism that assigns, ex ante, a probability to each equilibrium indicating how likely it is to obtain. We show how such a mechanism can be derived as the natural result of an adaptive learning process. This approach leads to a well-defined optimal policy problem, and has important implications for the conduct of government policy. We illustrate these implications using a simple model of technology adoption under network externalities.