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.     

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。     

The α-stable processes and their relationship with the exponent of self-similarity: Exchange rates of USA Dollar,Canadian Dollar,Euro and Yen

This research work analyzes the yields of the exchange rate parities of the American dollar, Canadian dollar, Euro, and Yen; estimates the basic statistics and the α-stables; carries out the Kolmogorov–Smirnov, Anderson–Darling, and Lilliefors goodness of fit tests; estimates the self-similar exponents and carries out the t and F tests, ruling out that the series of parities are multifractal. It also estimates the confidence intervals of the exchange rate parities and concludes that the estimated α-stable distributions are more efficient than the Gaussian distribution to quantify the risks of the market, and that the series are self-similar. Through the ? index, we can infer the risk of the events, indicating that the parities are anti-persistent and thus have short-term memory, mean reversion, and a negative correlation with the high risk in the short and medium term. The estimation and validation of the α-stable distributions and the self-similar exponent are important in the evaluation and creation of innovative investment instruments through financial engineering, risk administration, and the evaluation of derived products.     

Search and Wholesale Price Discrimination

Firms often choose not to post prices in wholesale markets, and buyers must incur costs to discover prices. Inspired by evidence of customized pricing (e.g., some customers pay up to 70% more than others) and search costs, I estimate a search model to study how personalized pricing impacts efficiency in a wholesale market. I find that price discrimination decreases total surplus by 11.6% and increases the sellers' profits by up to 52.1%. These effects are partially explained by price discrimination softening competition through a decrease in search incentives, illustrating how price discrimination may magnify the efficiency costs of search frictions.     

Financial crises and liquidity shocks a bank-run perspective

In contrast with the financial multiplier literature, this note explores a case in which the shock triggering a financial crisis stems from the financial sector itself; it is not a shock stemming from the real sector which gets amplified by, say, agency problems. The basic intuition is provided by the bank-run literature of the Diamond and Dybvig (1983) variety. Financial development is modeled as a mechanism that endows real assets (e.g., land and capital) with liquidity. However, liquidity can be impaired by shocks that are equivalent to a bank run. Liquidity creation enhances real asset prices, while a liquidity crunch generates asset price collapse. This bubble-looking episode is not driven by standard fundamentals, although it is fully in line with rationality. In this context, devoid of other frictions like price stickiness, the note examines the effect of monetary policy in the absence of nominal rigidities. It shows that preventing price deflation is not enough to offset relative (to output) asset price meltdown, but lower policy interest rates increase relative asset prices and steady-state output. Moreover, in the neighborhood of a first-best capital allocation, an increase in the liquidity of capital may lower the welfare of the representative individual, even if the higher liquidity of capital is sustainable and, hence, not destroyed by future crash – illustrating the possibility of “excessive” financial innovation. An extension of the basic model supports the conjecture that low policy interest rates may have given further incentives to the development of “shadow banking.”     

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.     

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.     

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.