Cumulants of random sum distributions

Consider a random variable S being the sum of a number N of independent and identically distributed random variables X_j (j = 1, 2, ...) where the number N is itself a non-negative integer-valued random variable independent of the X_j An explicit expression of the r-th cumulant of S is given in terms of the cumulants of N and X_j, Asymptotic properties of the distribution of S are also discussed.     

日本电力自由化的现状与展望

上世纪90年代以来,日本电力产业实施了大幅度地自由化改革.于1995年引入了批发电力的竞标制度,并于2000年在零售业开始对大用户实施了自由化.自由化改革既给产业发展带来了好处,也存在着弊端.如消费者可以自由选择电力公司等,但是其反面则是担心对稳定供给的损害.更为重要的是,作为网络服务的电力行业,发电、输电和配电在物理上是不可分离的,法理上的分离遇到了资本私有原理与共用设备之间存在的矛盾.而且,对经营者交叉进入具有不同性质的产业的经营行为,缺乏有效的法律规制.自由化改革暴露出来的弊端,需要决策者们更审慎地思考.     

Disaster Management from a POM Perspective: Mapping a New Domain

We have reviewed disaster management research papers published in major operations management, management science, operations research, supply chain management and transportation/logistics journals. In reviewing these studies, our objective is to assess and present the macro level “architectural blue print” of disaster management research with the hope that it will attract new researchers and motivate established researchers to contribute to this important field. The secondary objective is to bring this disaster research to the attention of disaster administrators so that disasters are managed more efficiently and more effectively. We have mapped the disaster management research on the following five attributes of a disaster: (1) Disaster Management Function (decision‐making process, prevention and mitigation, evacuation, humanitarian logistics, casualty management, and recovery and restoration), (2) Time of Disaster (before, during and after), (3) Type of Disaster (accidents, earthquakes, floods, hurricanes, landslides, terrorism and wildfires etc.), (4) Data Type (Field and Archival data, Real data and Hypothetical data), and (5) Data Analysis Technique (bidding models, decision analysis, expert systems, fuzzy system analysis, game theory, heuristics, mathematical programming, network flow models, queueing theory, simulation and statistical analysis). We have done cross tabulations of data among these five parameters to gain greater insights into disaster research. Recommendations for future research are provided.     

Recurrence formula on the joint distribution of sample skewness and kurtosis under normality

Abstract

Two recurrence relations with respect to sample size are given concerning the joint distribution of skewness and kurtosis of random observations from a normal population: one between the probability density functions and the other between the product moments. As a consequence, the latter yields a recurrence formula for the moments of sample kurtosis. The exact moments of Jarque-Bera statistic is also given.     

On the level probabilities for useful partially ordered alternatives in the analysis of variance

In the analysis of variance, we often encounter situations in which we want to test the null hypothesis of homogeneity of the normal means against various partially ordered alternative hypotheses. We study likelihood ratio tests for three useful types of alternatives: d-star, bipartite and broom tree. Especially, we give computational formulas for the level probabilities of the alternative types. The results permit us to obtain critical values for practical use.     

The Gap in the Subjective Wellbeing of M��ori and New Zealand Europeans Widened Between 2005 and 2009

We compared the self-reported subjective wellbeing of M??ori and New Zealand (NZ) Europeans in two NZ national postal samples. The first sample was collected in 2005 before the global financial crisis of 2007/2010. The second was collected in 2009 while the crisis was ongoing. Both samples contained large and arguably representative samples of the indigenous peoples of NZ, M??ori (Ns = 289 and 964) as well as the now-majority group, NZ Europeans (Ns = 2,769 and 4,073). NZ Europeans?? scores on the Personal Wellbeing Index (PWI) were near-identical across the 2005 and 2009 samples. However, M??ori, who were already lower than NZ Europeans on the PWI in 2005, showed a further decrease in 2009. We argue that this gap in wellbeing widened because material advantages experienced by NZ Europeans as a social group provides a systemic buffer which protects their personal wellbeing from the impact of economic privation. M??ori, who had already experienced systemic disadvantage, were not privileged with this buffer, and thus, the effects of the 2007/2010 global financial crisis impacted their personal wellbeing to a greater extent.     

What Determines the Size of the Nonprofit Sector?: A Cross-Country Analysis of the Government Failure Theory

This article is an empirical examination of the government failure theory using a cross-country data set. The government failure theory is represented in the major existing literature as providing a sound explanatory basis for an interesting characteristic of the nonprofit sector, that is, there is a large variability in nonprofit sector size from one place to another. Salamon et al. (Social origins of civil society: An overview, Working Papers of the Johns Hopkins Comparative Nonprofit Sector Project, 2000) examined this theory using the Johns Hopkins Comparative Nonprofit Sector Project (CNP) data set, and consequently rejected the government failure theory. However, by applying the panel analysis approach to the CNP data set, this article shows that the government failure theory should not have been so easily rejected.     

Life on the seesaw: a qualitative study of suicide resiliency factors for young gay men

While considerable research has highlighted the factors that increase gay youth suicide risk, there has been much less emphasis on protective factors. Using grounded theory methodology, we explored the suicide resiliency in eight young gay men in Aotearoa/New Zealand. Common themes emerged, including positive social norms and conditions, high levels of support, identification with role models and high self-esteem. These were integrated with "known" risk factors to form the Seesaw Model of Gay Male Suicide. This model demonstrates that the balance between risk and resiliency may be the key to gay suicide. Depending on the balance of these factors, youth might either be resilient, attempt suicide, or teeter somewhere in between. The current findings indicate that gay youth suicide prevention requires efforts to increase resiliency factors for this group.     

Episodic Volunteering in Sport Events: A Seven-Country Analysis

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - Given its ubiquitous nature, sport events are one of the most popular venues for episodic volunteering around the world....     

Students’ Vocational Choices and Voluntary Action: A 12-Nation Study

Previous research on student involvement suggested that business and engineering students manifest lowest rates of voluntary action. Similarly, it was thought that social science students are the most involved in voluntary action, with students of natural sciences and humanities in the middle. However, there were very few studies that empirically compared these assertions. Furthermore, these assertions were not investigated from cross-cultural perspectives. Based on a study of students in 12 countries (N = 6,570), we found that even when controlling for background variables, social science students are actually less engaged in voluntary action than other students. Engineering students are higher than expected on voluntary action while students of humanities are the most involved in voluntary action. When studying these differences in the 12 selected countries, local cultures and norms form different sets of findings that suggest that there is no universal trend in choice of academic field and voluntary action.