Sortabilities of Partition Properties

Consider the partition of a set of integers into parts. Various partition properties have been proposed in the literature to facilitate the restriction of the focus of attention to some small class of partitions. Recently, Hwang, Rothblum and Yao defined and studied the sortability of these partition properties as a tool to prove the existence of a partition with such a property in a given family. In this paper we determine the sortability indices of the seven most interesting properties of partitions providing a complete solution to the sortability issue.     

Reliability Evaluation of a Multi-state Network with Multiple Sinks under Individual Accuracy Rate Constraint

From the viewpoint of service level agreements (SLAs), Internet service providers and customers are gradually focusing on transmission accuracy. The Internet service provider should provide the specific bandwidth and individual accuracy rate requirement by their SLAs to each customer. This paper mainly evaluates the system reliability that a stochastic computer network can fulfill all requirements at all sinks. An efficient algorithm is proposed to generate the lower boundary points, minimal capacity vectors satisfying the demand and accuracy rate requirement for all sinks. The system reliability can be computed in terms of such points by applying recursive sum of disjoint products.     

反思现代主义:抒情性与现代性的相互表述

本文透过对战后台湾诗坛之语境的概述,并选取以抒情风格著称的两位诗人郑愁予和叶珊的诗歌<错误>和<屏风>进行文本细读,来阐释台湾现代诗中抒情性和现代性的相互表述.在现代主义启发下发展出来的现代诗强调情感微妙的象征,间接的暗示,它反对抒情主义--即贸贸然的满纸热情,但并非反抒情.现代诗吸取了中国古典诗传统的养分,却是绝对的现代.     

我有我的诗——奚密访谈录

董炎:奚密老师您好.能否谈谈您最早对诗歌产生兴趣是什么时候?在什么样的情况下?     

Balanced Confidence Regions Based on Tukey's Depth and the Bootstrap

We propose and study the bootstrap confidence regions for multivariate parameters based on Tukey's depth. The bootstrap is based on the normalized or Studentized statistic formed from an independent and identically distributed random sample obtained from some unknown distribution in R ^q . The bootstrap points are deleted on the basis of Tukey's depth until the desired confidence level is reached. The proposed confidence regions are shown to be second order balanced in the context discussed by Beran. We also study the asymptotic consistency of Tukey's depth-based bootstrap confidence regions. The applicability of the method proposed is demonstrated in a simulation study.     

Worker Satisfaction Following Employment Restructuring: Effects of Nonstandard Workers and Downsizing on Job Satisfaction in Taiwan

Since the 1980s, many employment relationships in Taiwan have evolved from regular and long-term to contingent and short-term, with widespread downsizing adding a considerable amount of instability. Since these changes are part of a global trend, there is a growing literature concerning their influences on worker attitudes and work life quality. Here we analyze the impacts of changing employment practices on the quality of work life among Taiwanese workers, specifically analyzing the effects of nonstandard work arrangements and downsizing on job satisfaction. Data are from the 2005 Taiwan Social Change Survey, First Wave of the Fifth Phase: Work and Life Module. Our two main findings are (a) degree of use of nonstandard workers exerts a range of negative impacts on job satisfaction among regular workers, and (b) degree of downsizing exerts similar negative effects. We also discuss the moderating impacts of using nonstandard workers as part of a downsizing strategy.     

Some Related Minima Stability and Minima Infinite Divisibility of the General Multivariate Pareto Distributions

This article studies the minima stable property of the general multivariate Pareto distributions MP^(k)(I), MP^(k)(II), MP^(k)(III), MP^(k)(IV) which can be applied to characterize the MP^(k) distribution via its weighted ordered coordinates minima and marginal distribution. Also, the multivariate semi-Pareto distribution (denoted by MSP) is discerned in the class of geometric minima infinite divisible and geometric minima stable distributions. If the exponent measure is satisfied by some functional equation, then the geometric minima stable property can be used to characterize the MSP distribution. Finally, the finite sample minima infinite divisible property of the MP^(k)(I), (II), and (IV) distributions is also discussed.     

Estimating Transition Probabilities for Ignorable Intermittent Missing Data in a Discrete-Time Markov Chain

This article considers a discrete-time Markov chain for modeling transition probabilities when multiple successive observations are missing at random between two observed outcomes using three methods: a na\"?ve analog of complete-case analysis using the observed one-step transitions alone, a non data-augmentation method (NL) by solving nonlinear equations, and a data-augmentation method, the Expectation-Maximization (EM) algorithm. The explicit form of the conditional log-likelihood given the observed information as required by the E step is provided, and the iterative formula in the M step is expressed in a closed form. An empirical study was performed to examine the accuracy and precision of the estimates obtained in the three methods under ignorable missing mechanisms of missing completely at random and missing at random. A dataset from the mental health arena was used for illustration. It was found that both data-augmentation and nonaugmentation methods provide accurate and precise point estimation, and that the na\"?ve method resulted in estimates of the transition probabilities with similar bias but larger MSE. The NL method and the EM algorithm in general provide similar results whereas the latter provides conditional expected row margins leading to smaller standard errors.     

Optimal Enhancement and Lifetime of Software Systems: A Control Theoretic Analysis

We develop an optimal control model to maximize the net value provided by a software system over its useful life. The model determines the initial number of features in the system, the level of dynamic enhancement effort, and the lifetime of the system. The various factors affecting these optimal choices are systems characteristics (e.g., complexity, age, quality), user learning, and process maturity. We also consider that there is a time lag between the addition of a feature and the realization of its benefit to users. The basic model is extended to consider the decision of replacing the existing system by a new one.