A family of estimators of population variance in two-occasion rotation patterns

Abstract

In this article, we have considered the problem of estimation of population variance on current (second) occasion in two occasion successive (rotation) sampling. A class of estimators of population variance has been proposed and its asymptotic properties have been discussed. The proposed class of estimators is compared with the sample variance estimator when there is no matching from the previous occasion and the Singh et al. (2013) estimator. Optimum replacement policy is discussed. It has been shown that the suggested estimator is more efficient than the Singh et al. (2013) estimator and a usual unbiased estimator when there is no matching. An empirical study is carried out in support of the present study.     

A counterexample to a conjecture of Schwartz

In 1990, motivated by applications in the social sciences, Thomas Schwartz made a conjecture about tournaments which would have had numerous attractive consequences. In particular, it implied that there is no tournament with a partition A, B of its vertex set, such that every transitive subset of A is in the out-neighbour set of some vertex in B, and vice versa. But in fact there is such a tournament, as we show in this article, and so Schwartz’ conjecture is false. Our proof is non-constructive and uses the probabilistic method.     

Employee perceptions of reputation: An ethnographic study

The ability of organizational members to identify and analyse stakeholder opinion is critical to the management of corporate reputation. In spite of the significance of these abilities to corporate reputation management, there has been little effort to document and describe internal organizational influences on such capacities. This ethnographic study conducted in Red Cross Queensland explores how cultural knowledge structures derived from shared values and assumptions among organizational members influence their conceptualisations of organizational reputation. Specifically, this study explores how a central attribute of organizational culture – the property of cultural selection – influences perceptions of organizational reputation held by organizational members. We argue that these perceptions are the result of collective processes that synthesise (with varying degrees of consensus) member conceptualisations, interpretations, and representations of environmental realities in which their organization operates. Findings and implications for organizational action suggest that while external indicators of organizational reputation are acknowledged by members as significant, the internal influence of organizational culture is a far stronger influence on organizational action.     

#iamafeminist as the “mother tag”: feminist identification and activism against misogyny on Twitter in South Korea

This article explores feminist activism via the hashtag #iamafeminist on Twitter in South Korea. This hashtag became an important platform for feminist identification and activism against misogyny following its start in 2015 as a way to resist prevailing anti-feminist sentiment in Korea. In addition to opposing stigmas regarding identifying as a feminist, #iamafeminist affords an inclusive frame that can promote feminist identification by sharing personal motives for and stories about being a feminist. Although critics dismiss the potential of hashtag activism due to its ephemeral nature, I argue that #iamafeminist—which I call the “mother tag”—was able to persist for three months by continuing to connect with real-time gender issues and by initiating activism against misogyny both online and offline.     

Bayesian principal component analysis with mixture priors

A central issue in principal component analysis (PCA) is that of choosing the appropriate number of principal components to be retained. Bishop (1999a) suggested a Bayesian approach for PCA for determining the effective dimensionality automatically on the basis of the probabilistic latent variable model. This paper extends this approach by using mixture priors, in that the choice dimensionality and estimation of principal components are done simultaneously via MCMC algorithm. Also, the proposed method provides a probabilistic measure of uncertainty on PCA, yielding posterior probabilities of all possible cases of principal components.     

使用汞分析器检测矿渣及水泥中的汞

以矿渣和水泥作为研究对象,采用汞分析器对其中的汞进行检测。水泥是一种建筑过程中广泛使用的高凝结材料。由于汞具有较大的毒性,因此必须严格检测建筑材料中汞的含量以降低其对人体的损害。作为水泥的替代物,矿渣具有许多的优点,例如价格低廉、毒性较小等。     

The ratification of ILO Conventions and the provision of unemployment benefits: An empirical analysis

This article tests the relationship between the ratification of International Labour Organization (ILO) Conventions and the provision of unemployment benefits. Statistical tests focus on two related issues: why countries ratify ILO Conventions on unemployment benefits, and whether ratification influences government spending on unemployment benefits. The main findings are that democracy, region, income, and globalization are the main factors influencing why countries ratify ILO Conventions on unemployment benefits. In turn, the ratification of ILO Conventions is systematically associated with higher spending if countries have ratified more than two Conventions.     

Implementation of JIT purchasing: An integrated approach

This article addresses the necessity of integration between buyer and supplier for effective implementation of the JIT system. An integrated lot-splitting model of facilitating multiple shipments in small lots is developed and compared with the existing approach in a simple JIT environment, single-buyer-single-supplier, under deterministic conditions for a single product. It is shown that the optimal policy adopted by the integrated approach can provide a strong and consistent cost-minimizing effect for both buyer and supplier over the existing approach.     

A class of weighted normal distributions and its variants useful for inequality constrained analysis

This article develops a class of the weighted normal distributions for which the probability density function has the form of a product of a normal density and a weight function. The class constitutes marginal distributions obtained from various kinds of doubly truncated bivariate normal distributions. This class of distributions strictly includes the normal, skew–normal and two-piece skew–normal and is useful for selection modelling and inequality constrained normal mean analysis. Some distributional properties and Bayesian perspectives of the class are given. Probabilistic representation of the distributions is also given. The representation is shown to be straightforward to specify distribution and to implement computation, with output readily adapted for required analysis. Necessary theories and illustrative examples are provided.     

A Study of Battered Women’s Purpose of Life and Resilience in South Korea

The principal objective of this study is to determine whether battered women’s purpose of life (meaning/value) affects resilience (self‐efficacy/communication efficiency/optimism). This purpose is meaningful in that it may help provide battered women with a new perspective of a changeable life, away from the negative perspectives frequently associated with domestic violence sufferers. The subjects of this study were 110 battered women staying at shelters located in Seoul and Gyeonggi Province, Korea. The survey was conducted between August 15 and September 20, 2010. The data were collected using questionnaires measuring sociodemographic variables, a purpose‐of‐life scale, and a resilience scale. The collected data were evaluated with frequency, correlation, and multiple regression analysis. The results of this study can be summarized as follows. First, the meaning and value of life positively influenced self‐efficacy. Second, only the meaning had a beneficial effect on communication efficiency. Third, only the value variable positively affected optimism. Therefore, this study implied that resilience is an important area in the context of spousal abuse. Based on these results, a program for enhancing the meaning of life is suggested to help domestic violence survivors to build up resilience.