Endogenous market power

In this paper we develop a framework to study markets with heterogeneous atomic traders. The competitive model is augmented as we provide traders with correct beliefs about their price impacts to define equilibrium with endogenously determined market power and show that such equilibrium exists in economies with smooth utility and cost functions and is generically determinate. Traders? price impacts depend positively on the convexity of preferences or cost functions of the trading partners and are subject to mutual reinforcement. Compared to the competitive model, the volume of trade is reduced, and hence is Pareto inefficient. The price effects of non-competitive trading depend on the convexity of marginal utility or cost function.     

Network effects, market structure and industry performance

This paper analyzes oligopolistic markets with network externalities. Exploiting a minimal complementarity structure on the model primitives that allows for pure network goods, we prove existence of non-trivial fulfilled-expectations equilibrium. We formalize the concept of industry viability, investigate its determinants, and show that it improves with more firms in the market and/or by technological progress. These results enlighten some well-known conclusions from case studies in the management strategy literature. We also characterize the effects of market structure on industry performance, which depart substantially from ordinary markets. The approach relies on lattice-theoretic methods, supplemented with basic insights from nonsmooth analysis.     

Labor market distortions and China's WTO accession package:: an applied general equilibrium assessment

The economic implications of China's accession to the World Trade Organization have been analyzed using applied general equilibrium techniques. We explore the consequences of trade reform in the presence of labor market distortions. A formal model of imperfect labor mobility is incorporated into a large-scale, stochastic applied general equilibrium framework with which the consequences of China's trade reform for net welfare are considered. The simulations suggest that distortions in China's labor market, including imperfect labor mobility, rural-urban migration, dual urban markets and surplus rural labor, have significant effects on trade liberalization outcomes and in some cases produce unexpected second-best results. Journal of Comparative Economics 31 (4) (2003) 774–794.     

The trade paradox persists under excise taxes

Brander and Krugman (1983) and Sertel (1988) followed by Krugman (1989), showed two sides of a ‘trade paradox’: The paradox in competition, viz. that opening trade (or increasing competition) may cause welfare to decline, and the paradox in efficiency, viz. that an increase in unit transport cost may increase welfare. In this paper, we consider the situation in an environment where interventionist trade policies are not permitted but each country is sovereign to impose an excise tax (or subsidy). The paradoxes persist under equilibrium excise taxes, reckoned both at the non-cooperative (Nash or dominant strategy) equilibrium and at the cooperative solution among tax-imposing authorities maximizing welfare. We also see that the paradoxes persist in a taxless environment where market equilibrium is Stackelberg rather than Cournot.     

Sectoral labor adjustment and monetary policy in a small open economy

This paper studies the welfare implications of sectoral labor adjustment cost in a two-sector small open economy model with sticky prices. We find that, when the economy faces external shocks, if monetary policy can stabilize the real economy, then sectoral labor market adjustment cost will lead to welfare loss. However, if monetary policy such as fixed exchange rates cannot stabilize real variables, then some degree of labor market friction will improve welfare instead and the gain will be significant. As a result, the welfare gap between flexible exchange rates and fixed exchange rates decreases with sectoral labor market friction. This is because the friction can offset some of the nominal rigidity and become a substitute for monetary policy to stabilize the real economy.     

How strong is the global integration of emerging market regions? An empirical assessment

This paper attempts to evaluate the time-varying integration of emerging markets from a regional perspective based on a conditional version of the International Capital Asset Pricing Model (ICAPM) with DCC-GARCH parameters that allows for dynamic changes in the degree of market integration, global market risk premium, regional exchange-rate risk premium, and local market risk premium. Our findings reveal several interesting facts. First, the time-varying degree of integration of four emerging regions under consideration, satisfactorily explained by the regional level of trade openness and the term premium of US interest rates, has recently tended to increase, but these markets still remain substantially segmented from the world market. Second, the local market risk premium is found to explain more than 50% of the total risk premium for emerging market returns. Finally, we show that conditional correlations usually underestimate and overstate the measure of time-varying market integration. The empirical results of this study have some important implications for both global investors and policymakers with respect to dedicated portfolio investments in emerging markets and policy adjustments.     

General equilibrium with price intervention policies: a computational approach

Three alternative formulations of general equilibrium under price intervention policies are presented in a computational framework. In the first, minimum or ceiling prices are supported by a government marketing agency. Revenues are recycled to consumers in the minimum price case, and losses covered by lump sum taxes in the ceiling case. Similarities to general equilibrium with taxes are stressed. In the second, sector specific minimum prices are considered similar to Harris-Todaro equilibria. In the third, government price supports operate through market interventions. Existence is discussed, numerical examples presented, and possible policy applications outlined.     

Collateral fluctuations in a monetary economy

This paper studies economy-wide fluctuations that occur endogenously in the presence of monetary and real assets. Using a standard monetary search model, we consider an economy in which agents can increase consumption, over and above what their liquid monetary asset holdings would allow, pledging real assets as collateral for monetary loans. It is shown that, if the liquidation value of real assets is below full market value, a stable cyclical equilibrium can emerge in consumption and capital around the unstable steady state. We also provide conditions for the existence of cycles of higher order, chaos and sunspot equilibria.     

Financial market imperfections and monetary policy strategy

In a model with imperfect money, credit and reserve markets, we examine if an inflation-targeting central bank applying the funds rate operating procedure to indirectly control market interest rates also needs a monetary aggregate as policy instrument. We show that if private agents use information extracted from money and financial markets to form inflation expectations and if interest rate pass-through is incomplete, the central bank can use a narrow monetary aggregate and the discount interest rate as independent and complementary policy instruments to reinforce the credibility of its announcements and the role of inflation target as a nominal anchor for inflation expectations. This study shows how a monetary policy strategy combining inflation targeting and monetary targeting can be conceived to guarantee macroeconomic stability and the credibility of monetary policy. Friedman's k-percent money growth rule, which can generate dynamic instability, and two alternative stabilizing feedback monetary targeting rules are examined.     

The econometric critique of computable general equilibrium modeling: the role of functional forms

Computable general equilibrium (CGE) models are among the most influential tools in applied economics. However, some serious questions have been raised about the empirical validity of these models. The core of the critique is that the parameter selection criteria are unsound and the use of first-order (CES class) functional forms imposes influential restrictions on the model's structure. A formal summary of the case against standard CGE modeling is presented, as is an alternative econometric-based modeling strategy which answers the critique. We then present a comparative CGE modeling experiment designed to assess the role of function forms. It is found that choice of functional forms affects not only industry-specific results, but aggregate results as well, even for small policy shocks.     

On spatial equilibria in a social interaction model

Social interactions are at the essence of societies and explain the gathering of individuals in villages, agglomerations, or cities. We study the emergence of multiple agglomerations as resulting from the interplay between spatial interaction externalities and competition in the land market. We show that the geography of the spatial economy affects significantly the properties of spatial equilibria. In particular, when agents locate on an open land strip (line segment), a single city emerges in equilibrium. In contrast, when the spatial economy extends along a closed land strip (circumference), multiple equilibria with odd numbers of cities arise. Spatial equilibrium configurations involve a high degree of spatial symmetry in terms of city size and location, and can be Pareto-ranked.     

中国宏观经济形势与政策2001-2002年

中国宏观经济政策应该遵循竞争性市场经济的均衡原则,并且其短期效应与长期效应应该是相互包容和内在一致的,短期的反周期需求管理在长期均衡的宏观经济政策框架下实现。中国经济需求管理的财政政策、货币政策、汇率政策长期组合应该是平衡财政预算、稳定货币供应与均衡汇率机制。     

Sources of exchange rate fluctuations with Taylor rule fundamentals

This paper investigates the sources of exchange rate fluctuations when monetary policy follows a Taylor rule interest rate reaction function. We first present a simple dynamic exchange rate model with Taylor rule fundamentals which is triangular in the long-run impacts of shocks to the output market, the interest rate differential, and the Taylor rule. We then proceed to assess the relative importance of various shocks in exchange rate determination by estimating a structural VAR with long-run identification restrictions based on the triangular structure of the model. We find demand shocks to be less important than in earlier VAR studies, with both supply shocks and nominal shocks explaining a substantial part of real exchange rate fluctuations.     

Income based price subsidies and parallel imports

We present a policy game where a Rich country has a higher ability than a Poor country to commit to certain elements of health policy such as providing income related price subsidies and allowing parallel imports (PI). When allowing PI is not a choice for the Poor country, the Rich country allows PI and both countries provide a subsidy to their poorer buyers as the subgame perfect equilibrium policies. However, when the Poor is able to PI a different equilibrium may arise. We show that the ability of the Poor to allow PI might increase welfare in this country even if it is never implemented. We also prove that as the Poor country gets richer, it will not be in their best interest to sign an agreement with the Rich to commit to not allowing PI.     

The top-dog and the lean and hungry look strategies in endogenous entry

This paper examines the strategic commitment behavior of heterogeneous leaders in an endogenous market structure. We demonstrate that each leader's investment level is independent of the other leaders' characters. Furthermore, we show that a leader over-invests (resp. under-invests) when an investment increases (resp. decreases) the leader's marginal profitability. Such an investment always makes leaders employ aggressive strategies in the competition relative to those in a no-commitment case. This result implies that aggressiveness of leaders is a robust observation in an endogenous market structure.     

Nonminimal product differentiation as a bargaining outcome

It is well known that in a duopoly model of product choice with quadratic transportation cost, the firms locate at the extreme endpoints of the market. Jehiel (1992, Int. J. Ind. Organ, 10, 633–641) has examined this model in an infinite horizon setting where in the initial period the firms choose location and in subsequent periods charge the Nash bargaining solution prices. Then, in the unique equilibrium both firms locate at the center of the market. This paper examines the case when the firms instead charge the prices determined by either the egalitarian bargaining solution or the Kalai–Smorodinski bargaining solution. It is shown that central agglomeration is an equilibrium. Furthermore, there is a continuum of symmetric equilibria in addition where the firms locate apart from each other. So the products are not necessarily minimally differentiated. Thus different bargaining solutions provide quite different outcomes.     

Belief-free equilibria in games with incomplete information: Characterization and existence

We generalize the results of Hörner and Lovo (2009) [15] to N-player games with arbitrary information structure. First, we characterize the set of belief-free equilibrium payoffs under low discounting as the set of feasible payoffs that are individually rational, jointly rational, and incentive compatible. Second, we provide necessary and sufficient conditions on the information structure for this set to be non-empty.     

The dynamic instability of dispersed price equilibria

We adopt an evolutionary framework to explain price dispersion as a time varying phenomenon. By developing a finite strategy analogue of the Burdett and Judd (1983) price dispersion model, we show that all dispersed price equilibria are unstable under the class of perturbed best response dynamics. Instead, numerical simulations using the logit dynamic show that price dispersion manifests itself as a limit cycle. We verify that limit cycles persist even when the finite strategy model approaches the original continuous strategy model. For a particularly simple case of the model, we prove the existence of a limit cycle.     

Constrained suboptimality in incomplete markets: a general approach and two applications

Summary. In this paper we re-examine generic constrained suboptimality of equilibrium allocations with incomplete numeraire asset markets. We provide a general framework which is capable of resolving some issues left open by the previous literature, and encompasses many kinds of intervention in partially controlled market economies. In particular, we establish generic constrained suboptimality, as studied by Geanakoplos and Polemarchakis, even without an upper bound on the number of households. Moreover, we consider the case where asset markets are left open, and the planner can make lump-sum transfers in a limited number of goods. We show that such a perfectly anticipated wealth redistribution policy, though consistent with the assumed incomplete financial structure, is typically effective. Received: August 14, 1995; revised version: April 11, 1997     

The opportunity cost of land use and the global potential for greenhouse gas mitigation in agriculture and forestry

This paper analyses the role of global land management alternatives in determining potential greenhouse gas mitigation by land-based activities in agriculture and forestry. Land-based activities are responsible for over a third of global greenhouse gas emissions, yet the economics of land-use decisions have not been explicitly modeled in global mitigation studies. In this paper, we develop a new, general equilibrium framework which effectively captures the opportunity costs of land-use decisions in agriculture and forestry, thereby allowing us to analyse competition for heterogeneous land types across and within sectors, as well as input substitution between land and other factors of production. When land-using sectors are confronted with a tax on greenhouse gas emissions, we find significant changes in the global pattern of comparative advantage across sectors, regions, and land types. Globally, we find that forest carbon sequestration is the dominant strategy for GHG emissions mitigation, while agricultural-related mitigation comes predominantly from reduced methane emissions in the ruminant livestock sector, followed by fertilizer and methane emissions from paddy rice. Regionally, agricultural mitigation is a larger share of total land-use emissions abatement in the USA and China, compared to the rest of the world, and, within agriculture, disproportionately from reductions in fertilizer-related emissions. The results also show how analyses that only consider regional mitigation, may bias mitigation potential by ignoring global market interactions. For example, USA-specific analyses likely over-estimate the potential for abatement in agriculture. Finally, we note that this general equilibrium framework provides the research community with a practical methodology for explicit modeling of global land competition and land-based mitigation in comprehensive assessments of greenhouse gas mitigation options.