Portfolio risk management in a data-rich environment

We study risk assessment using an optimal portfolio in which the weights are functions of latent factors and firm-specific characteristics (hereafter, diffusion index portfolio). The factors are used to summarize the information contained in a large set of economic data and thus reflect the state of the economy. First, we evaluate the performance of the diffusion index portfolio and compare it to both that of a portfolio in which the weights depend only on firm-specific characteristics and an equally weighted portfolio. We then use value-at-risk, expected shortfall, and downside probability to investigate whether the weights-modeling approach, which is based on factor analysis, helps reduce market risk. Our empirical results clearly indicate that using economic factors together with firm-specific characteristics helps protect investors against market?risk.     

Exploring factors influencing US millennial consumers’ use of tap-and-go payment technology

ABSTRACT

Although mobile payment (MP) represents a possibility for traditional brick-and-mortar US retailers to enhance the quality of customer service, mobile payment adoption in the US has lagged, with research regarding this phenomenon in the US seemingly in its embryonic stage. The current study contributes to the literature on mobile payment adoption in the US by investigating the factors on US millennial consumers’ use of mobile payment technology, operationalized in the study as tap-and-go payment systems. The study mirrors a study of the acceptance of mobile shopping technology among German consumers, with some extension. The study incorporated mobile payment risk perception, system trust, and socio-cultural influence into an extended technology acceptance model (TAM) to explore this issue. Results from a survey conducted among 357 US Millennials indicate that perceived ease of use of MP (PEOUMP); perceived usefulness (PUMP); and risk perception all influence attitude toward mobile payment (AttMP). System trust, socio-cultural influence, and AttMP all influence MP use intention. The paper discussed the limitations of the study and future research directions.     

白洋淀水质平衡分析初探

白洋淀是华北最大的淡水湖,素有“华北明珠”之称,具有沼泽和水域等生态系统。通过对白洋淀水质平衡分析,利用人工神经网络BP结构模型建立水质模型,提出白洋淀水环境保护措施。     

How should managers treat ethics in international business?

Business ethics concern the consideration of moral in corporate decision making. International managers may be confronted with a variety of ethical dilemmas, usually due to differences among national markets in what constitutes legal or acceptable practice. Beliefs about what constitutes ethical business behavior commonly stem from one of four moral philosophies: teleology, deontology, the theory of justice, and cultural relativism. A framework incorporating all four is presented here which should provide a useful decision tool for international managers. An application of the framework and the complexities associated with it are presented next. We conclude that an effective integration of the company's perspective on ethics and the business behavior of the employees is critical and that it depends on top management, and the entire organization, demonstrating that they are serious about ethical business behavior on an ongoing basis. © 1998 John Wiley & Sons, Inc.     

Islamic Work Ethic,innovative work behaviour,and adaptive performance: the mediating mechanism and an interacting effect

This study’s focus is on the relationship between Islamic Work Ethic (IWE) and adaptive performance with the mediating role of innovative work behaviour (IWB) and moderating role of ethical leadership among hospitality sector employees in Pakistan. Data were collected using questionnaires from 257 employees working in various hotels across Pakistan. Results indicate that IWE significantly predicts adaptive performance both directly and indirectly through IWB. In addition, results also confirm the moderating role of ethical leadership between IWE and IWB. Theoretical and practical implications are discussed.     

Implementing the AHP multi-criteria decision approach in buying an apartment in Jordan

Buying an apartment or a house is an important step in everyone’s life worldwide, to reach a settled and stable life. Several criteria are considered when buying an apartment or a house. In Jordan, apartments are customers’ preferred choices because of financial circumstances. It is not easy for a person to decide on the apartment’s specifications such as location, design, building design and finances. This study assists people in selecting an appropriate apartment using the Analytical Hierarchy Process (AHP), which is considered an important multi-criteria decision-making approach. Data used in this study were collected in Jordan; however, people worldwide can benefit from this study. The methodology used is twofold. First, feedback was considered from five investors in the real estate sector in Jordan about specifications that customers consider when buying an apartment. Second, several customers were asked about their preferences in a dream apartment using a pairwise comparison questionnaire, which was collected from 305 participants to obtain the priorities of 10 different apartment alternatives found in the Jordanian real estate market. The AHP technique is used to analyse the collected data to assist customers in reaching the best purchase decision.     

莲子心饮片含量测定方法优化

为了解决提取效率低而导致的市售莲子心含量项鲜有合格的问题,对莲子心饮片中有效成分的提取方法进行优化.分别对莲心碱的提取方式、提取溶剂以及提取溶剂体积进行了考察,利用优化后的提取方法制备莲子心饮片供试品溶液,选用Kromasil 100-5-C18(4.6 mm×150 mm)色谱柱,以乙腈-0.015 mol/L十二烷...     

水文序列变异对水库调度运行的影响研究

以安康水库为研究对象,探讨水文序列变异对水库调度运行结果的影响。利用Mann-Kendall秩次检验法、有序聚类和累积距平3种方法诊断1950-2014年安康入库径流序列,并确定变异点;同时,建立发电量最大模型,利用遗传算法优化求解变异前、后径流序列的调度结果。结果表明:安康水库入库径流在1984年处发生变异,变异后序列径流呈现减小的趋势;对比变异前,电站在变异后运行过程中多年平均发电量和整体运行水位都呈现降低的趋势,桃汛期内水库水位是上升的趋势。该研究在水电站设计、水库运行等方面具有重要的应用价值。