Expectation–maximization algorithm for system-based lifetime data with unknown system structure

AStA Advances in Statistical Analysis - In science and engineering, we are often interested in learning about the lifetime characteristics of the system as well as those of the components that made...     

The struggle for hegemony: the emergence of a counter-public sphere in post-1997 Hong Kong

The present study examines the struggle for hegemony in the public sphere by two different systems, following Hong Kong’s handover to China in 1997. It has been postulated that the new media, particularly social media, has become an important public sphere for the citizens of Hong Kong to engage in an anti-hegemonic struggle against China’s discursive encroachment into Hong Kong since 1997. Given that the public platform provided by legacy media has been bought out or coopted by China, new media has begun to serve as a subaltern public sphere to enable resisting the hegemony imposed by China. This was analyzed through a survey conducted as part of this study, which showed that people who are young, read the Apple Daily, have high expectations of local autonomy, and a high regard for press freedom are prone to using social media to obtain their social and political information. This article analyzes the implications of the emergence of a counter-China hegemonic public sphere.     

Analysis of advertising lifetime for mobile phone

The market for mobile phones has increased substantially. In an attempt to maintain or increase their market share, mobile phone companies invest a significant amount of their budget on advertising. In this paper, we analyze TV advertising lifetime data of five mobile phone companies in Korea. We identify the distribution of advertising lifetime and model the median life as a function of company-specific fixed effects, type of advertising, the number of new customers signed for the service, and the number of new advertisements placed by the competitors. We show how the fitted lifetime model can be applied to advertising policy such as switching time for new advertisement.     

Distribution patterns of and sampling plans forTetranychus urticae Koch (Acarina: Tetranychidae) on roses

Summary I sampledTetranychus urticae Koch (Acarina: Tetranychidae) regularly from four rose gardens in Kyoto and Nara Prefectures in 1988–1990. When mite density was low,T. urticae showed an uneven vertical distribution, being more abundant in the lower third and absent from the upper third of the plants. Mite density was less variable within than between plants, suggesting that a sampling plan which includes more leaves from different plants rather than from different levels of a plant is favourable. Spatial distribution ofT. urticae was nonrandom and followed the negative binomial distribution. In addition, both the Taylor’s power law and the Iwao’s patchiness regression described the distribution well. An empty-sample method for estimating mite density from the proportion of empty sampling units was developed. Sampling plans for determining the sample size required to reach a predetermined precision level, based on this method and by directly counting the mites, were designed. The counting method was more accurate than the empty-sample method. However, when the time factor was taken into account, the latter was more favourable, because it was faster than the former at a density range of 1.5–300 mites leaf⁻¹, which was most commonly encountered in the field.     

Moving, sensing intersectionality: a case study of Miss China Europe

Every year, Miss China Europe, a transnational beauty pageant organized for the Chinese diaspora, is held in the Netherlands. The hypervisuality of Chinese diasporic women at the event stands in painful contrast to their everyday invisibility, whether in the Netherlands, China, or elsewhere in the world. Informed by intersectional and transnational feminist scholarship, this empirical study zooms in on one group of women, ethnic Chinese born and/or growing up in the Netherlands, to identify and recuperate their neglected lived experience in a particular historical-cultural context. It takes their own voices as central, hopefully to contribute to their visibility. It aims to provide an understanding of diasporic Chinese women as living in the dynamics not only of their multiple subordinations but also of their subjective consciousness, experienced autonomy, and agency. Drawing insights from the subjective accounts of both contestants and audiences of Miss China Europe, I suggest that one way to foreground marginalized women's agency is to understand their intersectionality in terms of movements and sensory experiences. On the one hand, while the contestants articulated a readiness to perform their modern and yet Chinese selves, they were making movements along two intersecting axes of inequality and power relations - Chineseness and Dutchness - precisely to negotiate their sense of inequality and power relations. On the other hand, among the audiences, two major topics - the blood issue (or whether Chineseness should be defined by ancestry) and the language problem (or whether Chineseness should be defined by the ability to speak Chinese) - were raised regularly, underscoring a complex viewing experience of seeing and hearing, of the tension between visual and audio identifications.     

Robustness of the two-sample t-test umdeh violations of the homogeneity of farjance assumptioi

When the two-sample t-test has equal sample slies, it is widely considered to be a robust procedure (with respect to the significaoce level) under violatioa of the assuaptioo of equal variances. This paper is coa-earned with a quantification of the amount of robustness which this procedure has under such violations, The approach is through the concept of "religion of robustness" and the resluts show an extremely strong degree of robustness for the equal an extremely strong degree of robustness for the equal sample size t-test, probably more so than most statistyicians realise. This extremely high level of robustness, however, reduces quickly as the sample sizes begin to vary from equality. The regions of robustnes obtained show that while most users would likely be satisfied with the degree of robustness inherent when the two sample sizes each vary by 10% from equality, most would wish to be much more cautions when the variation is 20%. The study covers sample sizes n₁ -= n ² = 5(5)30(10)50 plus 10% and 20% variations thereof for the two-tailed test and nominal significance levels of 0.01 and 0.05.     

On the sums of probability functions of order statistics

When a random vector is independent and identically distributed, we have expressed the sums of the marginal probability functions of the order statistics of the random vector in terms of the common marginal probability functions of the random vector. We have also derived the relationships between the sums of the joint probability functions of two order statistics of the random vector and the common marginal probability functions of the random vector.     

公共行政当局以合同方式雇用人员时各类合同的适用范围

现时澳门公共行政当局以合同方式雇用人员的情况普遍,但是使用的合同类型多样,各类合同应有的不同适用范围卻鲜见有本地法律学术论文对此进行研究。本文尝试根据澳门现行法律和法学理论分析不同的合同各自应有的适用范围,并探讨该等合同在现行澳门法律下可能存在著的潜在问题。     

Best subset selection of autoregressive models with exogenous variables and generalized autoregressive conditional heteroscedasticity errors

Summary.  We develop an efficient way to select the best subset autoregressive model with exogenous variables and generalized autoregressive conditional heteroscedasticity errors. One main feature of our method is to select important autoregressive and exogenous variables, and at the same time to estimate the unknown parameters. The method proposed uses the stochastic search idea. By adopting Markov chain Monte Carlo techniques, we can identify the best subset model from a large of number of possible choices. A simulation experiment shows that the method is very effective. Misspecification in the mean equation can also be detected by our model selection method. In the application to the stock-market data of seven countries, the lagged 1 US return is found to have a strong influence on the other stock-market returns.