Structural stability for dynamical economic models

The paper discusses the implications for economics of the notion of structural stability. Definitions are given to characterize dynamical economic models generating movements the qualitative properties of which are conserved under perturbation. Consequences of these definitions, in particular for time evolutions which are globally or locally stable, are then presented through three theorems. Last, two examples — one in micro, one in macroeconomics — illustrate the type of results that can be obtained from such theorems.     

Urban economic base as a catalyst for movements in real estate prices

We examine the relation between housing prices in an MSA and its urban economic base. We create and employ new forward-looking employment growth indices that measure the urban economic strength of an MSA and find that it accounts for a significant and sizeable portion of the house price movements in that MSA. We argue that the forward looking measure is an indicator of future agglomeration growth for the MSAs. We further partition the urban economic growth into growth by various industries and track the attribution of their growth to housing prices over time. We find that for some MSAs, home prices are driven by the same set of industries over time, whereas for others, home prices are driven by a totally new set of industries in the later quarters, due to the birth of new industries. We also analyze the impact of the diversification of an urban economic base on home price volatility and observe that diversification decreases home price volatility. The result has larger implications for urban policymakers in selecting the appropriate type of industries relative to their existing mix of industries.     

A comparative analysis of the economic movements on the basis of a growth matrix

This paper considers the comparative analysis of the economic aggregates on the basis of the growth matrix and the corresponding blocks of growth. The aim is to synthetically encompass and analyze indicators of the aggregates (output, revenue, income, accumulation, etc.) through the blocks of growth. The block of growth represents a general scheme of growth of the ith and jth aggregates and enables the determination of important indicators P, Q, E and K. In other words, the block of growth is used to establish indicators of the ith and jth aggregates and, at the same time, for describing their absolute and relative changes as well as discovering the trends of these changes in the ensuing period. In this way, it is possible to analyze the structural and dynamic changes of aggregates and determine their behaviour in subsequent periods.     

Maintaining economic stability as a motive for statutory accounting requirements

The impact of selected accounting rules on economic stability is analysed. Maintaining economic stability is claimed to be an important motive for regulatory intervention. In the first part of the paper, a framework for analysing the usefulness of such stabilizing intervention is proposed. There are differences between countries relating to the kind of economic relationship regulators are focusing on. To what extent should standard setting activities attempt to stabilize relationships between debtors and creditors rather than between capital market players? Should the determination of distributable profits or investor information be the predominating tool of policy making? In relation to these issues several common accounting rules are examined for their contribution to economic stability.     

On local relative stability. With special reference to economic applications

Relative stability can be defined as the stability of equilibriumrays. Hence standard method of studying local stability by means of the spectrum of the Jacobian matrix at an equilibriumpoint cannot be used. This problem can often be circumvented by deriving from the original one a new system, having as state variables certainratios between the original variables, so that the equilibrium set will become a point and the standard method will apply. However, the Jacobian matrix at that point will be formed on the basis of a linear combination of the rows of the Jacobian matrix of the original system at a point of its equilibrium set and will normally be much more difficult to analyze. Here a method for studying local relative stability on the basis of the latter matrix is provided.

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Riassunto La stabilità relativa può esser definita come la stabilità diraggi di equilibrio. Quindi il metodo consueto consistente nello studiare la stabilità locale per mezzo dello spettro della matrice giacobiana in unpunto di equilibrio non può esser usato. Tuttavia questo problema spesso può esser superato qualora dal sistema originale possa esser derivato un altro sistema, avente come variabili di sato certi rapporti tra le variabili originarie, cosicché l'insieme di equilibrio del nuovo sistema si riduca ad un punto. In tal caso la matrice giacobiana in tale punto sarà formata sulla base di combinazioni lineari delle righe della matrice giacobiana del sistema originario in un punto del suo insieme di equilibrio, cosicché lo studio qualitativo della prima matrice sarà di regola molto più difficile di quello della seconda. Qui si propone un metodo per studiare la stabilità relativa locale sulla base della seconda matrice.

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I wish to thank M. Bianchi and E. Venini for their comments on previous drafts of this paper.     

A lemma on relative stability with an application to an economic case study

In the existing literature relative stability of trajectories is obtained under particular assumptions. In this paper a lemma is stated which provides a technique to prove relative stability in most general cases. Such a technique permits to replace the study of the stability of a balanced growth path by the study of the stability of a fixed point for an associated function. The lemma is applied to a case study, which could not be treated by means of usual techniques.     

A statistical test of the stability assumption inherent in empirical estimates of economic depreciation.

Realistic estimates of economic depreciation are required for analyses of tax policy, economic growth and production, and national income and wealth. THe purpose of this paper is to examine the stability assumption underlying the econometric derivation of empirical estimates of economic depreciation for industrial machinery and and equipment. The results suggest that a reasonable stability of economic depreciation rates of decline may exist over time. Thus, the assumption of a constant rate of economic depreciation may be a reasonable approximation for further empirical economic analyses.     

标准化系数与偏相关系数的比较与应用

在多元回归分析中,经常用标准化系数和偏相关系数来描述自变量的相对重要性,本文研究了这两个系数之间的数量关系及其统计意义,得出两者具有相同的正负号,证明出在二元回归中两者相对大小始终一致,而在自变量个数超过两个的回归模型中两者相对大小不一定完全一致,最后通过实例,说明在两者出现不一致情况下,判断自变量相对重要性的解决方法和应注意的问题。     

影响力系数和感应度系数计算方法的探析

讨论了影响力系数和感应度系数的主要计算方法。利用河北省2002年投入产出表,对不同计算方法进行了计算比较论证;阐述了影响力系数和感应度系数的确切含义,并对影响力系数和感应度系数的规范计算提出了一些看法和建议。     

不动点迭代法在齿形系数和应力修正系数计算中的应用

为了精确计算渐开线齿轮的齿形系数和应力修正系数,在计算过程中引入了不动点迭代法,并编制出计算齿形系数和应力修正系数的Matlab程序。最后,通过实例进行了验证。     

一种改进的Gini系数

Gini系数是以Lorenz曲线为基础而构造的一个用以衡量收入或财富分配不均等程度的测度指数。在收入分配理论中，Gini系数是一个重要的度量收入分配不平等程度的指标，但由于Gini系数与Lorenz曲线之间不是“一对一”的对应关系，即不同的Lorenz曲线具有相同的Gini系数，从而导致该指标的应用存在着一些缺陷。本文分析了Gini系数不能区分Lorenz曲线的原因，其次通过构造一种加权的Gini系数，对原Gini系数进行了修正，从而解决了原Gini系数无法区分不同的Lorenz曲线的问题。     

Social movements and globalization

Pierre Hamel, Henri Lustiger‐Thaler and Margit Mayer (eds.) Urban movements in a globalizing world John Guidry, Michael Kennedy and Mayer Zald (eds.) Globalizations and social movements: culture, power, and the transnational public sphere     

Musgrave’s “target saver” theory: Implications for macroeconomic stability and economic policy effectiveness”

Musgrave develops the concept of the “target saver,” in which the household saves in the present in order to finance a target level of consumption outlays in the future. The resulting household behavior is one in which a rise in the rate of interest in the present period reduces the amount of saving needed for future consumption, so that household saving is inversely rather than positively a function of the interest rate. The present study examines the potential implications of the target saver in the aggregate for macroeconomic stability and economic policy effectiveness.      

Assessing the economic knowledge and economic opinions of adults

This study investigates public knowledge of basic economics and public opinion on economic issues. The primary data sources are five national surveys, administered from 1992 to 1999, which contain a rich set of questions to conduct multiple tests and comparisons of the factors that affect economic knowledge and public opinion. As a whole, the results offer significantly stronger evidence of factors that influence knowledge and opinion than is possible from a study of a particular sample of adults using a single set of survey questions.The analysis proceeds in two ways following methods that were originally used with one of the five data sets, a 1992 survey of adults (Walstad, 1997). First, a regression model is specified and estimated with each data set to identify how personal characteristics, general education, course work in economics, income, and political party affect economic knowledge. Second, probit analysis is used to evaluate the effect of economic knowledge on public opinion on selected economic issues after controlling for the above variables. The results from the 1992 data serve as the baseline for comparing the findings across the other surveys.     

西部三大经济区城市经济增长收敛性研究

以塞尔指数衡量的我国西部三大经济区区域经济增长α收敛结果表明,西部大开发战略实施以来,该区域整体经济差异的主要构成为区域内经济差异,区域内差异与区域间差异之间存在着较大差距,而成渝经济区区域内经济差异所占整体经济差异的比重在三大经济区中最大。通过构建固定效应变系数条件收敛方程模型所进行的条件β收敛性分析进一步显示,在整体区域经济差异相对乐观的同时,区域核心城市经济增长多呈现发散状态,这将使该区域经济差异扩大。     

The economics of diamond price movements

Diamonds are traditionally classified into three different market segments —industrial, jewellery and investment. The empirical findings support the argument that diamond prices of these three group types respond differently to business cycles. Industrial diamond prices, especially those of natural stones, have been found to be influenced by the level of economic activity in general and the volume of manufacturing production in partiular. However, the price of synthetic diamonds, especially in grit form, have declined irrespective of the business cycle as a result of technological developments and the expansion of the market which enabled producers to gait scale advantages. Prices of jewellery diamonds have been found to be most highly correlated with disposable income. As could be expected, these price have also been found to be positively correlated with inflation rates and negatively correlated with real interest rates. Prices of investment diamonds have been found to be particularly sensitive to real interest rates, to the value of the exchange rates of the US dollar and, like other gems, to disposable income. The paper also describes and discusses the activity in various diamond markets and the business policy of De Beers, the ‘king’ of the rough diamonds.     

Post-war movements in teachers' salaries

Public sector white collar employees are a large and important part of the labour force. It is interesting, therefore, to look at the forces determining the pay of such workers, given the highly administered nature of the markets for their services, and at the operation of their negotiating procedures which have remained highly centralized at a time when there has been a growing tendency to move away from national bargaining. This paper looks at some aspects of the pay of one group of public employees – school teachers. The examination deals mainly with global aspects of teachers' pay, comparatively little attention being given to structural aspects of the problem. The discussion is confined to the full-time teaching force in England and Wales, though the growth in the number of part-time teachers and para-teaching personnel has been an important feature of the market in recent years.     

Principal component analysis of yield curve movements

An important issue in interest rate modeling is the number and nature of the random factors driving the evolution of the yield curve. This paper uses principal component analysis to examine (1) the inherent dimension of historical yield curve changes indicated by the significance of eigenvalues of the covariance matrix, (2) the practical dimension determined by a variance threshold, (3) the shape of the yield curve change associated with the first principal component, and (4) the persistence of this shape over time. We find that although the first two components explain 93% of the sample variation within a 90% confidence interval, the remaining components make statistically significant contribution to the covariance matrix. Consequently, we can establish a practical limit on the dimension only if we are willing to designate a threshold error variance. Further, our results on the persistence of the shape of the yield curve shift associated with the first component depend upon this threshold. If all components are included, the hypothesis that the shape persists between two sample time periods is rejected. On the other hand, if all but the first six components are eliminated, the hypothesis is not rejected.     

对铁路工程价差系数的探讨

铁路工程目前的价差调整方式主要是采用相对于某种编制办法的基期价每年(或季度)由铁道部发布材料价差系数进行价差调整,本文阐述了铁路工程价差系数的发展过程及其特点,定量地分析了太中银项目"某项目部"铁路价差系数对其工程造价的影响,对铁路工程项目的材料价差调整具有一定的指导意义。