基于复杂供应链库存管理策略的系统动力学研究

在分析了具有不同提前期和加工时间的复杂供应链特点基础上，研究了混合CONWIP／Kanban库存管理思想与同步CONWIP库存管理思想在复杂供应链上的应用。同时借助Vensim建模平台。针对这两种管理思想建立了基于复杂供应链系统的动态仿真模型，并对模拟结果进行了分析。     

Over-savings and hyperbolic discounting

Hyperbolic discounting models are widely seen as implying that consumers do not save enough, in accordance with the observed low rates of savings of some households. This paper qualifies this view by showing that hyperbolic consumers may ‘oversave’ in the short run. The result extends to uncertainty on future income and does not depend on whether preferences are present-biased or future-biased. A generalized comparative statics analysis of self-control is introduced, and its relationship to the analysis of uncertainty on discount factors is emphasized.     

On the evolutionary edge of altruism: a game-theoretic proof of Hamilton’s rule for a simple case of siblings

We offer a game-theoretic proof of Hamiltons rule for the spread of altruism. For a simple case of siblings, we show that the rule can be derived as the outcome of a one-shot prisoners dilemma game between siblings.JEL Classification: A13, C70, D64Correspondence to: Oded Stark, ZEF, University of Bonn, Walter-Flex-Strasse 3, 53113 Bonn, GermanyWe are indebted to an anonymous referee and to Uwe Cantner for helpful comments and suggestions. Partial financial support from the National Institute on Aging (grant RO1-AG13037) and from the Humboldt Foundation is gratefully acknowledged.     

Short-memory equilibrium in stochastic overlapping generations economies

In stochastic OLG exchange economies, we show that short-memory equilibria—the natural extension from deterministic economies of steady states, low-order cycles, or finite state-space stationary sunspots equilibria—fail to exist generically in utilities. As a result, even with independent and identically distributed exogenous shocks there is serial correlation in endogenous economic variables in equilibrium. This arises even if utilities are time-separable, some goods inferior, and there are no technological lags. Hence, the origins of economic fluctuations can be traced only to the demographic structure of a heterogeneous agent, multiple-good economy.     

Monetary regimes and the co-ordination of wage setting

A recent literature argues that a strict monetary regime may reduce equilibrium unemployment by disciplining wage setters, as wage setters abstain from raising wages to avoid a monetary contraction. However, in this literature the wage setters are assumed not to co-ordinate their wage setting. The present paper argues that precisely because a strict monetary regime may discipline the unco-ordinated wage setting, thus lowering unemployment in the unco-ordinated outcome, it also reduces wage setters’ incentives to co-ordinate. It is shown that an accommodating monetary regime may reduce equilibrium unemployment, via the strengthening of the wage setters’ incentives to co-ordinate.     

影响盈余信息含量的因素——来自A股的实证结果

研究中习惯用回报／盈余关系来表示会计盈余的信息含量。通过A股的实证结果发现，当时间窗口为公告日前后60关时，回报／盈余关系较显著；盈余的持续性越高，回报／盈余关系越显著；非线性的模型比线性模型的解释能力更强。但是模型总体的R2水平都较低，这可能是由于研究方法的缺陷、市场的非理性、盈余本身信息含量低等原因造成的。     

THE JOINT ARRIVAL AND DEPARTURE PROCESS FOR THE M/M/l QUEUE

We consider the M/M/1-queue and derive an explicit expression for the joint distribution of the number of arrivals and the number of departures in [0, t), given the number of customers initially present. The derivation is almost purely combinatorial, it avoids the use of generating functions, and immediately yields a simple probabilistic interpretation of the result.     

基于Intranet结构的中小企业MIS构建

知识经济的发展源自于以信息技术、网络技术等高科技及其产业为发展标志的科技革命。中小企业应用Intranet技术，构建企业现代管理信息系统，对提高中小型企业的管理水平和经济效益是十分有益的。     

Fiscal stabilizations: When do they work and why

This paper studies the determinants and channels through which fiscal contractions influence the dynamics of the debt-to-GDP ratio and GDP growth. Using data from a panel of OECD countries, the paper shows that the success of fiscal adjustments in decreasing the debt-to-GDP ratio depends on the size of the fiscal contraction and less on its composition. The rate of growth of output matters too, but higher GDP growth does not drive the success of a fiscal stabilization. In contrast, whether a fiscal adjustment is expansionary depends largely on the composition of the fiscal maneuvre. In particular, stabilizations implemented by cutting public spending lead to higher GDP growth rates. The effects of the composition on growth work mostly through the labor market rather than through agents’ expectations of future fiscal policy. Finally, the evidence suggests that successful and expansionary fiscal contractions are not the result of accompanying expansionary monetary policy or exchange rate devaluations.     

The unbearable tightness of being in a monetary union: Fiscal restrictions and regional stability

We study how constrained fiscal policy can affect macroeconomic stability and welfare in a two-region model of a monetary union with sticky prices and distortionary taxation. Both government spending and taxes can be used to stabilize regional variables; however, the best welfare outcome is obtained under some tax variability and constant regional inflations. We use a variety of rules to characterize constrained fiscal policy and find that strict fiscal rules coupled with a monetary policy that targets union-wide inflation result in regional inflation stability and the welfare costs of such rules are not as unbearable as one would expect. Fiscal authorities can enhance welfare by targeting the regional output gap, while targeting regional inflation is less successful since inflation stability is guaranteed by the central bank.