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Purpose The purpose of this paper is to contribute to the literature in three ways: first, the authors investigate the impact of the sampling errors on optimal portfolio weights and on financial investment decision. Second, the authors advance a comparative analysis between various domestic and international diversification strategies to define a stochastic optimal choice. Third, the authors propose a new methodology combining the re-sampling method, stochastic optimization algorithm, and nonparametric stochastic dominance (SD) approach to analyze a stochastic optimal portfolio choice for risk-averse American investors who care about benefits of domestic diversification relative to international diversification. The authors propose a new portfolio optimization model involving SD constraints on the portfolio return rate. The authors define a portfolio with return dominating the benchmark portfolio return in the second-order stochastic dominance (SSD) and having maximum expected return. The authors combine re-sampling procedure and stochastic optimization to establish more flexibility in the investment decision rule.Design/methodology/approach The authors apply the re-sampling procedure to consider the sampling error in the optimization process. The authors try to resolve the problem of the stochastic optimal investment strategy choice using the nonparametric SD test by Linton et al. (2005) based on sub-sampling simulated p values. The authors apply the stochastic portfolio optimization algorithm with SSD constraints to define optimal diversified portfolios beating benchmark indices.Findings First, the authors find that reducing sampling error increases the dominance relationships between different portfolios, which, in turn, alters portfolio investment decisions. Though international diversification is preferred in some cases, the study’s results show that for risk-averse US investors, in general, there is no difference between the diversification strategies; this implies that there is no increase in the expected utility of international diversification for the period before and after the 2007-2008 financial crisis. Nevertheless, the authors find that stochastic diversification in domestic, global, and Europe, Australasia, and Far East markets delivers better risk returns for the US risk averters during the crisis period.Originality/value The originality of the idea in this paper is to introduce a new methodology combining the concept of portfolio re-sampling, stochastic portfolio optimization with SSD constraints, and the nonparametric SD test by Linton et al. (2005) based on subsampling simulated p values to analyze the impact of sampling errors on optimal portfolio returns and to investigate the problem of stochastic optimal choice between international and domestic diversification strategies. The authors try to prove more coherence in the portfolio choice with the stochastically and the uncertainty characters of the paper. [ABSTRACT FROM AUTHOR]

Purpose Nearly 200m people in the world experience considerable functioning difficulties. Also, more than three-fourth of the population aged 50 years and over is suffering from some kind of disability in India, China, Ghana, Russia, Mexico and South Africa. Despite the compelling nature of this issue, evidence on socioeconomic disparity in the occurrence of disability is lacking throughout the world and particularly in the aforementioned countries. The purpose of this paper is twofold – first, to examine the socioeconomic inequalities in the prevalence of disability in the selected countries; and second, to investigate the cross-country differentials in the prevalence of disability by socioeconomic characteristics.Design/methodology/approach The authors use data from the Study on Global Ageing and Adult Health (SAGE) conducted in China, Ghana, India, Mexico, Russia and South Africa during 2007–2010. Disability scores have been constructed using Item Response Theory Partial Credit Model based on eight health and functioning domains. Bivariate analysis, concentration curves, concentration indices and multivariate regressions have been used in the analysis presented in this paper.Findings The authors find that the prevalence of disability varied considerably across sociodemographic groups. Moreover, this variation is not uniform across all countries. Also, age, Sex, work status, years of schooling and economic status emerged out as significant predictors of disability among the studied countries.Originality/value This is perhaps the first study which examines the socioeconomic inequality in disability conceptualized in a comprehensive manner among older adults spread across low to upper middle income countries. The alarming level of prevalence of disability among sociodemographic disadvantage groups calls for immediate attention in terms of detailed study of risk factors, effective policy and timely intervention. [ABSTRACT FROM AUTHOR]

Purpose – Scheduling needs to be concise and well-determined but able to respond to the ever-changing and uncertain market or environment against the constraints of production capacity, resources, time frame, etc. The purpose of this paper is to model and solve a scheduling problem with another domain perspective that adopts the concept of agent, and an agent-based scheduling environment is proposed for solving the scheduling problem, in which three agents are developed, i.e. a sales agent, a scheduling agent, and a production agent. Design/methodology/approach – The modeling and development of the proposed agent-based scheduling environment and its agents under constraints are discussed. Constraint priority scheduling concepts are applied to the environment and its agents, and the feature of responding to customer change orders is included in the model. The proposed agent-based scheduling environment with three agents is applied to a lamp-manufacturing company in China as a case study, and the integrated agent-based approach is also illustrated in the case study. Findings – Throughout the autonomous communication between agents in the proposed model, a constraint-prioritized schedule is generated to fulfill customer orders and customer change orders, as well as to achieve a better scheduling performance result. From the simulation results and analysis in the case study, satisfactory results show that the proposed model can generate a constraint-prioritized schedule for the studied company that can completely fulfill customer orders, adjust and fulfill customer change orders, and achieve a better scheduling result. Originality/value – In this paper, the scheduling problem is modeled and solved by using the domain perspective of agent-based approach. By using an agent-based approach, the agents can be implemented to represent manufacturing resources or aggregations of resources. Under the proposed modeling approach, the collaboration across the entire scheduling activities can be enhanced, and the efficiency and effectiveness in the scheduling activities can also be increased. [ABSTRACT FROM AUTHOR]

Purpose - This paper seeks to study capital market efficiency, because results may infer that there are predictable properties of the time series of prices of traded securities on organized markets in Hong Kong, the third largest exchange in the Pacific-Basin of Asia. Design/methodology/approach - The weak form of the efficient markets hypothesis is examined to indicate its usefulness in terms of the results of this study. Do the data indicate that the times series of closing prices is a random walk or are their predictable properties? Findings - It will be noted from the results that the model identifies predictive short-term properties that exist in the data of returns of Hong Kong Exchanges for the period studied. Research/limitations/implications - Conclusions are limited to those firms studied and the time period covered. Originality/value - For the securities exchanges in Hong Kong, evidence indicates that the weak form of the efficient markets hypothesis does not characterize the trading market. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to investigate how the information about haze, a term used in China to describe the air pollution problem, is portrayed on Chinese social media by different types of organizations using the theoretical framework of the health belief model (HBM). Design/methodology/approach – A content analysis was conducted based on the 756 posts retrieved from Sina Weibo, the top microbloging platform in China, following the simple random sampling method. χ2 analysis was conducted to examine the relationships across the three types of organizations (governmental organizations, non-governmental organizations, and corporations) and the use of the HBM concepts (perceived susceptibility, perceived severity, perceived benefits, perceived barriers, self-efficacy, and cues to action) in terms of haze and its threat to health. Findings – The results of this study indicated that corporations posted more Weibo messages categorized as perceived benefit and most of these posts are related to their products, while governmental organizations posted fewer Weibo messages categorized as perceived severity. Social implications – This study provides health decision makers and media consumers with knowledge about how to use social media more effectively in terms of haze-related issues. Originality/value – Given the severity of air pollution and the influential role microblogging takes, the study aims to fill the gap in the limited literature on haze information dissemination on social media in China. In addition, this study aims to shed theoretical light on HBM as applied to a non-westernized context. [ABSTRACT FROM AUTHOR]

The article informs about a research paper by Ming Zhao, Zhengdong Huang and Liping Chen of Huazhong University of Science and Technology, at Wuhan, People's Republic of China. The study focuses on a method of pressure calculation for carrying out the multidisciplinary design optimization (MDO) of the tool head system in the heavy-duty CNC machine tool for multi-pocket closed hydrostatic guideways.

The article informs about a study related to the performance analysis of a slanted hydraulic pump of the Taipuhe Pump Station located in Taipuhe valley, Shanghai, China, that has an axial flow. It focuses on analysis of several characteristics of hydraulic pump related to its safe operation, which include impeller elevation, unsteady flow and hydraulic thrust. Further, it mentions that the flow passage was analyzed and the hydraulic thrust was calculated to prevent damage to the bearings.

A mathematical model and numerical method for water flow and solute transport in a tidal river network is presented. The tidal river network is defined as a system of open channels or rivers with junctions and cross sections. As an example, the Pearl River in China is represented by a network of 104 channels, 62 nodes, and a total of 330 cross sections with 11 boundary sections for one of the applications. The simulations are performed with a supercomputer for seven scenarios of water flow and/or solute transport in the Pearl River, China, with different hydrological and weather conditions. Comparisons with available data are shown. The intention of this study is to summarize previous works and to provide a useful tool for water environmental management in a tidal river network, particularly for the Pearl River, China. [ABSTRACT FROM AUTHOR]