A monetary vector error correction model of the Euro area and implications for monetary policy

In this paper, a vector error correction model for Euro area money, prices, output, long-term interest rate and short-term interest rate with three identified cointegration relations is specified. It is shown that Euro area money and prices can be considered as variables that are integrated of order two or I(2), that is, they have to be differenced twice to become stationary. Accordingly, the relation between money, prices and other macroeconomic variables is analyzed in an econometric framework which is suited for the analysis of I(2)-variables. Monetary policy implications are derived from the estimated system.First revision received: May 2002/Final revision received: May 2003I thank Helmut Lütkepohl, Jürgen Wolters, and two anonymous referees for helpful comments. Financial support from the Deutsche Forschungsgemeinschaft (SFB 373) is gratefully acknowledged.     

Causality between income and emission: a country group-specific econometric analysis

Empirical studies of the Environmental Kuznets Curve (EKC) examine the presence or otherwise of an inverted U-shaped relationship between the level of pollution and the level of income. Customarily, in the diagram of EKC the level of income is shown on the horizontal axis and that of pollution on the vertical axis. Thus, it is presumed that the relationship between income and pollution is one of unidirectional causality with income causing environmental changes and not vice versa. The validity of this presumption is now being questioned. It is being asserted that the nature and direction of causality may vary from one country to the other. In this paper, we present the results of a study of income–CO₂ emission causality based on a Granger causality test to cross-country panel data on per capita income and the corresponding per capita CO₂ emission data. Briefly, our results indicate three different types of causality relationship holding for different country groups. For the developed country groups of North America and Western Europe (and also for Eastern Europe) the causality is found to run from emission to income. For the country groups of Central and South America, Oceania and Japan causality from income to emission is obtained. Finally, for the country groups of Asia and Africa the causality is found to be bi-directional. The regression equations estimated as part of the Granger causality test further suggest that for the country groups of North America and Western Europe the growth rate of emission has become stationary around a zero mean, and a shock in the growth rate of emission tends to generate a corresponding shock in the growth rate of income. In contrast, for the country groups of Central and South America, Oceania and Japan a shock in the income growth rate is likely to result in a corresponding shock in the growth rate of emission. Finally, causality being bi-directional for the country groups of Asia and Africa, the income and the emission growth rates seemed to reinforce each other.     

无线办公自动化系统

基于无线技术管理信息系统是无线技术发展的研究热点,通过无线技术,人们可以不受时间地点的限制,及时获取自己需要的信息.J2ME是无线系统开发的一个主要平台,它具有广阔的硬件运行平台、良好的移植性和较短的开发周期.本文将无线技术应用于传统的办公自动化系统,以J2ME作为开发平台,分析、设计和实现了一个无线办公自动化系统的用户界面模块.本文对于J2ME技术进行了系统的研究,分析了MIDP和RMS实现难点,并进行实际应用.MIDP提供了一套标准的用户界面控件,而这些控件是以屏幕模型为设计理念,与桌面系统差异很大.RMS提供了一个小型的数据库,为移动设备提供持久性存储.     

OK you are now an approved supplier—but you still do not get orders: Understanding the case of the P-Card

The purchase card (P-Card) was introduced in the 1990s as a payment mechanism for smaller value items so that purchase paperwork is reduced, itemized reporting and control become possible, and purchasing and payment are decentralized at the user level. Since the late 1990s, with E-procurement and B-to-B E-commerce, the possibilities of P-Card use have magnified exponentially. However, the adoption and success of P-Cards in organizations has been short of initial expectations.Using P-Cards with approved suppliers is an ideal situation for both buyers and sellers. In practice however, many P-Card users seem to buy many items from suppliers who are not on the approved supplier list. To make payments to these “new” suppliers, organizations need to make exceptions resulting in paperwork, costs, and loss of business for approved suppliers. However, there are many P-Card users who indeed follow the company-approved list and these users may be called “P-Card conforming users.”This article takes a knowledge-based approach and presents a model for conforming P-Card use (CPU). The model is tested in an organization, and results are used to derive managerial and research implications. While orientation training of P-Card users is important, both business marketers and purchasing departments need to reach out directly to the P-Card user to ensure that approved supplier lists work well in an electronic age.     

The relationship between tourism,CO2 emissions and economic growth: a case of Mediterranean countries

This study explores the impact of tourism on economic growth considering CO₂ emissions utilizing panel data techniques for a sample of Mediterranean countries. The cointegration tests reveal that there is a positive long-run equilibrium between tourism, CO₂ emissions and economic growth. This positive long-run relationship may suggest that tourism increases the level of CO₂ emissions and has a statistically significant impact on economic growth in Mediterranean countries. Emirmahmutoglu and Kose (2011. Testing for Granger causality in heterogeneous mixed panels. Economic Modelling, 28(3), 870–876.) test results reveal that the tourism-led growth hypothesis, which suggests that tourism contributes to economic growth, is valid for Egypt, Italy, and Spain. Additionally, there exists a bidirectional relationship between tourism and economic growth both in Morocco and Turkey.     

Social distancing in airplane seat assignments

This paper addresses the airplane passengers’ seat assignment problem while practicing social distancing among passengers. We proposed a mixed integer programming model to assign passengers to seats on an airplane in a manner that will respect two types of social distancing. One type of social distancing refers to passengers being seated far enough away from each other. The metric for this type of social distancing is how many passengers are seated so close to each other as to increase the risk of infection. The other type of social distancing refers to the distance between seat assignments and the aisle. That distance influences the health risk involved in passengers and crew members walking down the aisle. Corresponding metrics for both health risks are included in the objective function. To conduct simulation experiments, we define different scenarios distinguishing between the relative level of significance of each type of social distancing. The results suggest the seating assignments that best serve the intention of the scenarios. We also reformulate the initial model to determine seat assignments that maximize the number of passengers boarding an airplane while practicing social distancing among passengers. In the last part of this study, we compare the proposed scenarios with the recommended middle-seat blocking policy presently used by some airlines to keep social distancing among passengers. The results show that the proposed scenarios can provide social distancing among seated passengers similar to the middle-seat blocking policy, while reducing the number of passengers seated close to the aisle of an airplane.     

A dynamic panel data analysis of snow depth and winter tourism

This paper analyses the relationship between the number of overnight stays and different measures of snow depth based on panel data covering 28 Austrian ski resorts for the period 1986/87–2005/06. Using the dynamic heterogeneous panel data technique of Pesaran, Shin, and Smith (1999), we found a long-run relationship between the number of overnight stays, amount of snow depth, weighted real GDP per capita of the major countries of visitor origin, and price index of accommodation services. The long-run elasticity of overnight stays with respect to snow depth was 0.10. However, for high-elevation resorts the evolution of the number of overnight stays was independent of variations in snow depth. Furthermore, the long-run elasticity of the number of overnight stays with respect to weighted real GDP per capita of the country's visitors was much greater for high-elevation resorts than for low-elevation resorts. Finally, early Easter holidays were significantly and positively related to winter tourism demand.     

Insider ownership and firm performance: An examination of restaurant firms

This study investigated the relationship between insider ownership and firm performance in the restaurant industry. Convergence-of-interests and entrenchment hypotheses were tested via cross-sectional and panel two-stage least square (2SLS) GMM estimation methods for linear and non-linear models. The study found that there is an overall positive and significant relationship between insider ownership and firm performance. The quadratic model showed that restaurant firm performance increased until insider ownership was between 38 and 40%, whereas it decreased after that point. Consistent with the quadratic model, the piece-wise regression model showed that insider ownership had a positive impact on firm performance within a range of 5–25% and a negative influence beyond 25% insider ownership. Consequently, this study revealed that convergence-of-interests and entrenchment effects of insider ownership co-exist in the restaurant industry. While convergence-of-interests effects are effective, an excessive granting of stock options or awards to managers could weaken firm performance due to entrenchment effects.     

基于T-LDA2vec的高校图书馆信息素质教育主题挖掘与演化分析

为了深入研究高校图书馆信息素质教育领域的发展趋势和演化过程,收集了1998—2023年的1 606篇相关文献,经过数据清洗和预处理后,构建T-LDA2vec混合模型,用于主题建模和文本分析。在时间趋势上,揭示高校图书馆信息素质教育领域存在学术繁荣期和学术调整期两个关键时期。在学术繁荣期相关文献数量迅速增长,而学术调整期文献数量急剧下降,反映该领域正在经历学术调整。继而,运用T-LDA2vec模型进行主题挖掘,确定每个时期的最佳主题数量,并将主题划分为高校教育评估、师资培养、情报管理、网络化图书馆服务、高校图书馆素质教育服务、心理素质与教育表现、地方信息化与课程发展、数字化图书馆员培养八大类别。结果表明,计算不同时间段内各主题的强度,并通过交互式条形图描述热点主题。研究发现,一些主题在不同时期内保持较高的强度,表明它们在相关文献中具有重要影响力。师资培养、教学改革及高校图书馆资源创新与服务质量等主题在不同时期内维持了较高的强度。通过主题演化分析,揭示了不同时期内主题之间的关联和演化过程,指出高校图书馆信息素质教育研究的关注焦点逐渐从基础服务向资源创新、知识管理和在线教育等领域演化。该研究...     

浅析基于J2EE体系结构的网上商场设计

采用J2EE＋Web Services技术,通过对一个网上商城的建模、编程、模拟,实现了各种商务功能,对中小型用户,性能十分优越;对一些大型网站,采用合理的数据库,也能充分实现移植。