Leaving EMU: a real options perspective

The real option implicit in a country's decision of whether to leave an existing monetary union when there is uncertainty over the future benefits of this move is examined. The theoretical model used is calibrated for the current Euro-12 area by proxying policymakers’ inflation preferences with unemployment rates and debt-to-GDP ratios. A robust group of countries is observed that would choose to remain within EMU consisting of Belgium, Finland, Greece and Italy; France and Spain loosely also belong to this core. Only Luxembourg would robustly want to leave EMU; Ireland and The Netherlands, however, complement that core closely.     

Why persistent high inflation impedes growth? An empirical assessment of threshold level of inflation for India

In the policy debate on growth–inflation trade-off and the role of monetary policy in managing the trade-off in the short-run, theoretical and empirical research suggests the presence of a country specific threshold level of inflation. Empirical findings of this paper suggest that for India the threshold level of inflation could be around 6%. The inflation target for monetary policy may have to be somewhat lower than the growth maximizing threshold, since any positive inflation could be a risk to inclusive and sustainable growth objective.     

Can Poverty be Alleviated in China?

The 2000s witnessed the third poverty alleviation wave in China. Compared with its predecessors, the third wave distinguished itself by new interventions and redefined standards for the National Poor Counties. This paper evaluates the effectiveness of the new program using a data set consisting of 1,411 of China's western and central counties from 2000 to 2010. It combines the propensity score matching method with the difference‐in‐differences approach, which helps to avoid selection bias and track the policy impact on variables of interest at each time point. It is found that the non‐western local governments tended to manipulate data on income and output growth to maintain the special transfer payments disbursed exclusively to the National Poor Counties. It is also shown that the program failed to improve the infrastructure and sanitary conditions in general.     

直流电机系统的建模技术研究

本文针对传统直流电机的模型建立问题，基于曲线拟合技术，提出了简洁有效的参数辨识方法。由于实际的直流电机模型正反向参数差别很大，因此本建模方法中对直流电机的正向模型和反向模型分别对待。实验结果验证了所建立的直流电机模型的优越性能。     

非等变角对数螺旋线在扭曲叶片绘型中的应用

扭曲叶片的绘型常采用的单锥面展开法 ,因是基于局部相似 ,所以 ,存在误差 ,无法分析 ,难以编程。笔者在有关水泵问题研究中 ,对扭曲叶片绘型的单锥面展开法进行了改进 ,给出利用非等变角对数螺旋线进行叶片绘型的新方法。这种方法能够很好地控制β角的变化规律 ,并能对误差进行分析和修正 ,便于编程计算 ,易于操作 ,在水泵设计中有广泛的实用价值。     

基于可持续发展的国家物质流分析

210003本文采用物质流分析方法,研究了1995—2002年中国经济系统的物质输入和输出等相关指标,发现经济系统的物质需求总量和物质输出总量巨大,自然环境的生态压力短期内无法得到缓解;人均物质需求量不高,物质生产力也很低;环境库兹涅茨曲线呈现出倒“U”型,最高点出现在人均收入700美元,然后进入下降通道;技术水平是影响物质需求总量变化的关键因素;出口能源中的煤炭存在巨大隐藏流是导致生态贸易赤字的主要原因。     

The association between two random elements: A complete characterization and odds ratio models

For random elements X and Y (e.g. vectors) a complete characterization of their association is given in terms of an odds ratio function. The main result establishes for any odds ratio function and any pre-specified marginals the unique existence of a corresponding joint distribution (the joint density is obtained as a limit of an iterative procedure of marginal fittings). Restricting only the odds ratio function but not the marginals leads to semi-parmetric association models for which statistical inference is available for samples drawn conditionally on either X or Y. Log-bilinear association models for random vectors X and Y are introduced which generalize standard (regression) models by removing restrictions on the marginals. In particular, the logistic regression model is recognized as a log-bilinear association model. And the joint distribution of X and Y is shown to be multivariate normal if and only if both marginals are normal and the association is log-bilinear.Acknowledgements The author thanks both referees for their helpful comments which improved the first draft of the paper.     

传统企业电子商务转型的价值曲线与收支曲线

本文阐述了传统企业电子商务转型的必要性，提出并分析了传统企业电子商务转型的价值曲线和收支曲线。     

The future of the mobile phone business

One of the fastest growing technologies of our times is that of mobile phones. In this article we use the assumption that the diffusion of mobile technology, as measured by the number of active mobile accounts, follows the well known S-curve of natural growth in competition systems. The accuracy of the logistic fit is tested against actual data for the whole world, Europe, China and the GSM system. Using the produced models predictions concerning the future of mobile business are deliberated.According to these models active mobile accounts around the globe are expected to grow from 1.7 billion in 2004 to approximately 2 billion in 2008, reaching a peak penetration of 29.2%. Growth barriers, apart from the age of the potential user, are also low income and extreme poverty. Europe, early adopter of mobile technology and leader in active mobile accounts against all other regions in the world, has apparently reached a peak with almost every European, apart from the very young or very old, using a mobile phone. The mobile market in China is anticipated to exceed 500 million active accounts and may increase even further depending on the economic and social reform that is currently under way in that part of the world. GSM will most likely remain the leading mobile technology in the future as it is today.The growth process for the world, Europe, and the GSM system is almost completed and during this stage instabilities may occur before the potential emergence of a new wave of growth.     

The Relationship between Federal Deficits and Real Interest Rates

Real interest rates fluctuated a great deal since the 1970s. In the 1980s federal deficits accelerated and their impact on both nominal and real interest rates gained lots of attention. Based on monthly and quarterly data from January 1971 to December 1997 it is found that federal deficits had significant positive effect on the real interest rates: Personal income or consumption are found to have significant positive impact on the real interest rates, whereas expected inflation and money supply are found to have negative impact on the real interest rates. These findings are consistent with the conventional economic theory.