基于异质消费群体的生态供应链网络均衡模型

文章针对不同消费者对新产品、再制造产品存在效用异质性的情况,构建了一个由制造商和消费者市场组成的两层生态供应链超网络模型,优化目标为经济效益最大化、环境影响和风险最小化。考虑环境规制及产品的可再造比例对整个供应链绩效的影响,利用网络均衡理论描述不同主体的独立行为和主体之间、产品之间相互影响的竞争行为。数据分析结果表明,系统整体效益以及企业对产品可再造比例的选择很大程度上取决于产品创新效率和政府补贴方式。     

Walrasian General Equilibrium Allocations and Dynamics in Two-Sector Growth Models

This paper analyzes and solves miniature Walrasian general equilibrium systems of momentary and moving equilibria. The Walrasian framework encompasses the fundamental neoclassical and classical two‐sector growth models; the families of solutions of steady‐state and persistent growth per capita in various competitive two‐sector economies are parametrically characterized. Moreover, the endogenous behavior of relative prices and the sectoral allocation of primary factors are analyzed in detail. The technology parameters of the capital good industry are decisive for obtaining long‐run per capita growth in closed (global) economies. A review of the literature complements the theorems on the general equilibrium allocations, dynamic systems, and the time paths of Walrasian two‐sector economies.     

A Two-Sector Model of Endogenous Growth with Leisure

This paper analyses the equilibrium dynamics of an endogenous growth model with physical and human capital in which leisure enters the utility function. The inclusion of leisure introduces a potential source of non-convexities in our optimization problem and leads to the possible existence of multiple balanced growth paths. This multiplicity of optimal stationary solutions is linked to the assumption that education has no effect on the quality of leisure, and hence a relatively more educated economy may choose to grow faster, and devote more time to income-directed activities. To characterize the set of optimal solutions in our non-concave optimization framework we develop a new method of analysis that should be of interest in related applications.     

Long-Run Effects of Monetary Expansion in a Two-Sector Model of Endogenous Growth

This paper explores the long-run effects of monetary expansion by introducing a cash-in-advance constraint into one of the basic models of endogenous growth. In our model, the real side of the economy consists of two production sectors, one of which produces a final good that can be used either for consumption or for investment and the other produces new human capital. Both sectors use physical and human capital under constant returns to scale technologies. We first characterize the balanced-growth equilibrium and then examine how a rise in money growth affects the relevant variables, such as the long-term growth rate and the relative prices.     

Optimal Patent Protection in a Two-Sector Economy

This article addresses the issue of optimal patent protection in an economy with a downstream and an upstream sector. The key insight is that higher patent protection in the downstream sector raises the incentives of agents to do R&D in that sector but discourages innovation in the upstream sector because of a market size effect. Hence, higher patent protection in the upstream sector accelerates growth whereas higher patent protection in the downstream sector slows it down. If some innovation is socially desirable, optimal patent protection is necessarily higher in the upstream than in the downstream sector.     

Numerical Computation of Equilibrium Bid Functions in a First-Price Auction with Heterogeneous Risk Attitudes

We use numerical methods to compute Nash equilibrium (NE) bid functions for four agents bidding in a first-price auction. Each bidderi is randomly assigned:r _i [0,r _max], where 1 –r _i is the Arrow-Pratt measure of constant relative risk aversion. Eachr _i is independently drawn from the cumulative distribution function (·), a beta distribution on [0,r _max]. For various values of the maximum propensity to seek risk,r _max, the expected value of any bidder's risk characteristic,E (r _i ), and the probability that any bidder is risk seeking,P (r _i > 1), we determine the nonlinear characteristics of the (NE) bid functions.     

Socioeconomic Impacts of Public Forest Policies on Heterogeneous Agricultural Households

Nepal has a long history of returning public forests to local people as part of its community forestry programme. In principle the community forestry programme is designed to address both environmental quality and poverty alleviation. However, concern has been expressed that forest policies emphasise environmental conservation, and that this has a detrimental impact on the use of community forests in rural Nepal where households require access to public forest products to sustain livelihoods. To study the effect of government policies on forest use, an economic model of a typical small community of economically heterogeneous households in Nepal was developed. The model incorporates a link between private agriculture and public forest resources, and uses this link to assess the socioeconomic impacts of forest policies on the use of public forests. Socioeconomic impacts were measured in terms of household income, employment and income inequality. The results show that some forest policies have a negative economic impact, and the impacts are more serious than those reported by other studies. This study shows that existing forest policies reduce household income and employment, and widen income inequalities within communities, compared to alternative policies. Certain forest policies even constrain the poorest households?? ability to meet survival needs. The findings indicate that the socioeconomic impacts of public forest policies may be underestimated in developing countries unless household economic heterogeneity and forestry??s contribution to production are accounted for. The study also demonstrates that alternative policies for managing common property resources would reduce income inequalities in rural Nepalese communities and lift incomes and employment to a level where even the poorest households could meet their basic needs.     

Catching-up and Regulation in a Two-Sector Small Open Economy

Deregulation is often aimed at reducing mark-up pricing in technologically stagnant sheltered sectors. The paper shows that this may decrease the process of catching-up and welfare since it shifts resources away from R&D-intensive tradables sectors. Catching-up and deregulation are analyzed in an R&D-based growth model that allows for international capital mobility, trade, and spillovers. Knowledge spillovers raise the productivity of R&D in the exposed sector which results in catching-up. In the long run, the economy grows at the exogenous world growth rate. Capital mobility speeds up convergence. Temporary shocks have long-lasting effects as the economy exhibits hysteresis.     

Optimal Redistributive Taxation in a Search Equilibrium Model

This paper characterizes optimal non-linear income taxation in an economy with a continuum of unobservable productivity levels and endogenous involuntary unemployment due to frictions in the labour markets. Redistributive taxation distorts labour demand and wages. Compared to their efficient values, gross wages, unemployment, and participation are lower. Average tax rates are increasing. Marginal tax rates are positive, even at the top. Finally, numerical simulations suggest that redistribution is much more important in our setting than in a comparable Mirrlees-type setting.     

An Empirical Equilibrium Job Search Model With Search on the Job and Heterogeneous Workers and Firms

In this article we present and estimate a synthesis of previous equilibrium search models, allowing for continuous distributions of workers' opportunity costs of employment as well as firms' productivities. The model allows for on-the-job search, and we assume that job offer arrival rates for workers are independent of their labor-market state. We derive the theoretical implications of these assumptions, we provide simulations, and we develop a semiparametric estimation procedure that we apply to a dataset of individual labor-market histories.     

Differential Provision of Solid Waste Collection Services in the Presence of Heterogeneous Households

A model of household refuse production is presented in which individuals differ in their distaste for the waste stock and the supply of waste collection services is continuous in pick-up frequency. The inclusion of pick-up frequency into household solid waste management analyses has already been shown to have policy implications. In fact, even in the absence of the waste stock externality, a system of uniform consumption taxes and legal (or curbside) disposal and recycling subsidies has been found to be necessary (and sufficient) to induce households to socially optimally allocate their resources when illegal disposal (or simply dumping) incentives exist but a per unit punishment system for dumping is lacking. This policy is here concluded to be no longer feasible; instead, a system of differential consumption taxes and recycling subsidies and uniform legal disposal subsidies is found to be optimal (but possibly nonimplementable). In the presence of heterogeneous households, which are however identifiable on the basis of their relative location to the landfill site, an optimal and implementable policy is then shown to require a differential provision of collection services.     

Retraining the Unemployed in a Model of Equilibrium Employment

An equilibrium model of search and matching is developed to analyse the effects of retraining the unemployed on the market for skilled (or semi-skilled) workers. Versions of the model with free entry of vacancies and fixed numbers of jobs are considered. The latter environment exhibits multiple equilibria. While subsidized training (and enforced participation) is justified on employment grounds, it cannot be justified on efficiency grounds. Policies that, ceteris paribus , lower unemployment, also reduce the incentive to train. When such policies are introduced to a training economy, training may cease and unemployment can rise.     

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.     

Learning and Equilibrium Selection in a Monetary Overlapping Generations Model with Sticky Prices

We study adaptive learning in a monetary overlapping generations model with sticky prices and monopolistic competition for the case where learning agents observe current endogenous variables. Observability of current variables is essential for informational consistency of the learning setup with the model setup but generates multiple temporary equilibria when prices are flexible and prevents a straightforward construction of the learning dynamics. Sticky prices overcome this problem by avoiding simultaneity between prices and price expectations. Adaptive learning then robustly selects the determinate (monetary) steady state independent from the degree of imperfect competition. The indeterminate (non-monetary) steady state and non-stationary equilibria are never stable. Stability in a deterministic version of the model may differ because perfect foresight equilibria can be the limit of restricted perceptions equilibria of the stochastic economy with vanishing noise and thereby inherit different stability properties. This discontinuity at the zero variance of shocks suggests one should analyse learning in stochastic models.     

On the Neutrality of Redistribution in a General Equilibrium Model with Public Goods

Models on private provision of public goods typically involve a single private good and linear production technology for the public good. We study a model with several private goods and nonlinear (strictly concave) production technology. We revisit the question of „neutrality” of government interventions on equilibrium outcomes and show that relative price effects that are absent with a single private good and linear production technology become a powerful channel of redistribution in this case. Contrary to previous results, redistributing endowments in favor of contributors is shown to be neither necessary nor sufficient for increasing the equilibrium level of public good.     

A Model of Creative Destruction with Undiversifiable Risk and Optimising Households

This paper studies optimal household behaviour in a model of creative destruction. The saving technology is characterised by stochastic returns that follow a Poisson process. It is shown that equilibrium conditions with optimising households differ substantially from equilibrium conditions where investment in R&D is determined by firms. Three out of four market failures disappear and a new market failure resulting from a complementarity in financing R&D is identified. Studying the social optimum shows that it contains as the special case of risk neutrality the social optimum derived in the literature.     

On the Long-Run Distribution of Capital in the Ramsey Model

We study issues related to the long-run distribution of wealth in two variants of Ramsey's model of optimal capital accumulation. First we show that, in the case where a government levies a progressive income tax, there exist infinitely many stationary equilibria in which all households own positive capital stocks. Moreover, it is demonstrated that non-stationary equilibria can exhibit complicated dynamics. Then we discuss the case where households exercise market power on the capital market and we show that this may also lead to equilibria in which all households own positive amounts of capital. Journal of Economic Literature Classification Numbers: E62, O41.     

Heterogeneous Households,the Distribution of Wealth,and the Laursen-Metzler Effect*

To study the effects of a terms-of-trade deterioration the paper constructs a dynamic model with heterogeneous households that maximize intertemporal utility. It shows that insofar as this shock leads to a redistribution of wealth-an outcome ignored by the literature because of the representative-agent assumption invariably adopted-it may give rise to an initial current-account deficit and nonmonotonic adjustment paths. the paper also buttresses the argument that heterogeneous-household models help explain the observed “excess smoothness” of consumption.     

Equilibrium Partner Switching in a Bargaining Model With Asymmetric Information

We study a model in which the seller of an indivisible object faces two potential buyers and makes an offer to either of them in each period. We find that the seller's ability to extract surplus from them depends crucially on the value of the cost of switching from one buyer to the next. If the seller is pessimistic about the buyers' valuations and there is a switching cost, however small, then the market is a natural bilateral monopoly; the second buyer is never called on. If the switching cost is zero, or if the seller is optimistic, then switching, and possibly recall of the original buyer, may occur.