The Marshallian macroeconomic model: A progress report

In this progress report, we first indicate the origins and early development of the Marshallian macroeconomic model (MMM) and briefly review some of our past empirical forecasting experiments with the model. Then we present recently developed one-sector, two-sector and n-sector models of an economy that can be employed to explain past experience, predict future outcomes and analyze policy problems. The results of simulation experiments with various versions of the model are provided to illustrate some of its dynamic properties that include “chaotic” features. Last, we present comments on planned future work with the model.     

Inter-enterprise arrears in economies in transition

In the context of economies in transition, the paper argues that an excessive liquidity squeeze could throw the economy into a persistent state of low economic activity. In such bad equilibrium, enterprise transactions become largely demonetized, with a chain of arrears, a form of involuntary credit, spreading over the entire system. The empirical analysis of the Romanian experience seems to support the view advanced in the paper.     

Informal settlements’ needs and environmental conservation in Mexico City: An unsolved challenge for land-use policy

The aim of this article is to analyze the effectiveness of land-use policy in Mexico City in controlling the expansion of informal human settlements in peri-urban zones of high ecological value. It is argued that Mexico City's land-use policy has been reactive and internally inconsistent, failing to take informal settlements into account, has not offered the poor access to housing with adequate services and greater security in terms of land tenure, and lacks the necessary financial resources and institutional capabilities for providing solutions to these problems. Through a case study of informal settlement management policy in the Tlalpan Delegation,¹ applied in what has been termed SC or “Conservation Land,”² we conclude that local government exhibits an inability to confront the new challenge of urban sustainability, that it resorts to conventional solutions which give rise to contradictory situations where political decision-making prevails over ecological considerations, so land-use policy is permissive and does not halt informal urban expansion in areas of high environmental value.     

Labor Market Analysis and Public Policy: The Case of Morocco

This article uses detailed industry and household data to understandwhy Morocco's labor market performed poorly in 1985–95.The data indicate that marked structural changes and weak demandin the product market were responsible. This article makes twocontributions to the literature. The first is specific: it underscoresthat the demand for labor is a derived demand and that the performanceof the product market is an important determinant of the performanceof the labor market. The second is more general: it demonstratesthat this kind of microeconomic analysis, using data sets thatare often available in developing countries, can inform policydesign.     

Payroll taxes,wages and employment: Identification through policy changes

This paper investigates the effect of changes in payroll taxes on wages and employment in Argentina. The analysis, based on administrative data, focuses on the impact of a series of major changes in payroll taxes which varied across geographical areas. This setup offers two main advantages over previous studies. First, using longitudinal data, the variation in tax rates across space and time provides a plausible source of identification of their effects on employment and wages. Second, the use of legal tax rates for each area at each point in time provides a remedy for the measurement error bias raised by the use of empirical rates constructed from observed tax and wage bills. Once this bias is accounted for, the results indicate that changes in payroll tax rates are only partially shifted onto wages, and they point to the absence of any significant effect on employment.     

Co‐movements in commodity prices: a note based on network analysis

This article analyses co‐movements in a wide group of commodity prices during the time period 1992–2010. Our methodological approach is based on the correlation matrix and the networks inside. Through this approach we are able to summarize global interaction and interdependence, capturing the existing heterogeneity in the degrees of synchronization between commodity prices. Our results produce two main findings: (a) we do not observe a persistent increase in the degree of co‐movement of the commodity prices in our time sample, however from mid‐2008 to the end of 2009 co‐movements almost doubled when compared with the average correlation; (b) we observe three groups of commodities which have exhibited similar price dynamics (metals, oil and grains, and oilseeds) and which have increased their degree of co‐movement during the sampled period.     

可靠性维修的管理系统(续)

五、技术状态的计算 估计成套装置和已经安装的设备的技术状态所使用的算法,其定义和制定这个项目的众多主要目标之一。对各种型号设备的技术状态是分别计算的,并用两个指标中的一个指标来表示,一个是在考虑周期内的失效概率（正常情况以一年为一个周期）,另一个是残余寿命或预期寿命。技术状态用数值表示,数值小,说明设备处于完好状态,失效概率小和预期寿命长;数值大,则说明在考虑周期内失效概率大或它的预期寿命即将终止。     

可靠性维修的管理系统

西班牙Soluziona公司开发和建立了一套维修管理系统,使可靠性为中心的维修（RCM）方案付诸实施,并优化年度维修计划和日常维修管理工作。     

Involuntary unemployment and inventories: An exploratory model of equilibrium and pure competition

We build up a model where the combination of labor supervision costs and non-uniform tastes results in a perfect-foresight equilibrium with positive involuntary unemployment and inventories even when prices and wages are assumed to be perfectly flexible. We show that the model could explain a positive association between the real wage and the level of employment (contrary to the standard post-Keynesian model), and a negative one between inventories and employment.