Energy and habitat: Designing a sustainable urban ecosystem

As the world's cities grow so new ways of satisfying their demands for food and fuel resources will have to be found, especially in the third world where total fuel demands are expected to expand several fold in one generation. An ecological model for a future complex urban community is presented to illustrate the place of energy in a growing system and how habitat—the physical component—possesses life cycles interdependent with living species. Recycling, biomass fuels, telecommunications, marine living and the propagation of viable organizations are all elements that will enable the globe to sustain future expanding metropolises.     

On the (nonlinear) relationship between exchange rate uncertainty and trade — An investigation of US trade figures in the group of seven

In this paper bilateral models formalizing monthly growth of US imports and exports are employed to investigate the potential of nonlinear relationships linking exchange rate uncertainty and trade growth. Parametric linear and nonlinear as well as semiparametric time series models are evaluated in terms of fitting and ex ante forecasting. The overall impact of exchange rate variations on trade growth is found to be weak. In periods of large exchange rate variations, trade growth forecasts gain from conditioning on volatility. Empirical results support the view that the relationship of interest might be non-linear and, moreover, lacks homogeneity across countries and imports vs. exports. JEL no. C14, C22, F31, F41     

A medium-N approach to macroeconomic forecasting

This paper considers methods for forecasting macroeconomic time series in a framework where the number of predictors, N, is too large to apply traditional regression models but not sufficiently large to resort to statistical inference based on double asymptotics. Our interest is motivated by a body of empirical research suggesting that popular data-rich prediction methods perform best when N ranges from 20 to 40. In order to accomplish our goal, we resort to partial least squares and principal component regression to consistently estimate a stable dynamic regression model with many predictors as only the number of observations, T, diverges. We show both by simulations and empirical applications that the considered methods, especially partial least squares, compare well to models that are widely used in macroeconomic forecasting.     

Applying Diffusion Models with Regional Heterogeneity

Recent studies of innovation diffusion have investigated cross-country heterogeneity, but implicitly assumed within-country homogeneity. As such, these studies potentially overlook within-country variations in diffusion patterns, which may be even more important to marketing managers and researchers alike. The current paper is concerned with such intra-country variations using one of many possible a priori segmentation schemes, namely geographic segmentation. It empirically demonstrates that when substantial regional variations in diffusion patterns occur, taking account of these regional differences improves both short- and long-term forecasting under certain conditions. Regional differences in diffusion patterns also provide some important normative implications.     

中国男性时尚杂志广告投放现状与趋势分析

近几年,我国男性时尚杂志发展迅速。以精英男性为目标读者的男性时尚杂志成为备受关注且待开发的新领域。男性杂志的繁荣也潜藏着越来越多的商机,为杂志广告的发展提供了肥沃土壤。本文旨在分析在这样一个变幻的媒体环境中,男性时尚杂志上的广告投放现状及发展趋势。     

Dual sourcing of a newsvendor with exponential utility of profit

Dual sourcing strategies supplement inflexible, low-cost country sourcing with quick response manufacturing. Due to short product life cycles, combined with uncertain demand, dual sourcing strategies are very common in several industries, in particular in the sporting goods or fashion industries.Even though scholars have given some attention to the analysis of dual sourcing strategies, the importance of the decision-maker’s risk preferences has not been covered yet.In this paper we analyse dual sourcing strategies using an extended single-product newsvendor model with two order points. Different risk preferences will be modelled using an exponential utility function. Within realistic parameter ranges, the optimal order quantities can only be numerically computed. The findings of this paper show that dual sourcing strategies are always preferable to an exclusive offshore approach, as long as the onshore ordering costs are smaller than the selling price of the considered product. The more risk-averse the decision-maker, the smaller the offshore order quantity will be.     

预测与对策:未来中国房地产价格走势分析——以成都市为例

全球金融危机对中国房地产价格影响很大,通过对一系列影响因素的分析,发现这一时期人们的心理预期是所有影响因素中最为敏感的因素,能严重影响中国房地产价格。研究表明,四川省成都市的房地产价格走势与全国房地产价格走势接近,因而能够以该城市的房地产价格作为研究样本,在各种心理预期量化的基础上,预测出未来三年中国房地产价格并提出了相应的政策建议。     

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.     

港口货流预测分析及软件技术

物流技术随着电子商务的崛起已逐渐成为新经济研究的焦点。随着入世的临近及入世的实现，作为物流中心枢纽的港口，其货（物）流将会发生极大的变化，无论是货种、流向还是货物公司及运输方式、运输始发地等，都会有较大的改变，迫切需要行之有效的预测方法及软件。基于灰色理论的预测方法较传统的统计预测方法有较大的不同，它不需要多数据统计的样本，是解决少数据不确定系统预测的有效方法，对我国新港多，港口统计数据不稳定不全面等情况尤为合适。本预测分析软件运用最新的数据库与界面技术，使得预测快捷、直观、界面友好。