Fisher Information in Type II Progressive Censored Samples

Recently, progressively Type II censored samples have attracted attention in the study and analysis of life-testing data. Here we propose an indirect approach for computing the Fisher information (FI) in progressively Type II censored samples that simplifies the calculations. Some recurrence relations for the FI in progressively Type II censored samples are derived that facilitate the FI computation using the proposed decomposition. This paper presents a standard recurrence relation that simplifies computation of the FI in progressively Type II censored samples to a sum; FI in collections order statistics (OS). We compute the FI in a collections of progressively Type II censored samples for some known distributions.     

Discrete adaptive design in attribute life testing

Properties of a discrete adaptive design in attribute life testing situation are studied. It is shown that the design is strongly consistent and asymptotically normal. Some examples are discussed to show that the design could be used in a wide range of ields, Finally, we give some simulation results to compare the discrete adaptive desigin with some continuous optimal designs.     

Lag Length Selection for Unit Root Tests in the Presence of Nonstationary Volatility

A number of recent papers have focused on the problem of testing for a unit root in the case where the driving shocks may be unconditionally heteroskedastic. These papers have, however, taken the lag length in the unit root test regression to be a deterministic function of the sample size, rather than data-determined, the latter being standard empirical practice. We investigate the finite sample impact of unconditional heteroskedasticity on conventional data-dependent lag selection methods in augmented Dickey–Fuller type regressions and propose new lag selection criteria which allow for unconditional heteroskedasticity. Standard lag selection methods are shown to have a tendency to over-fit the lag order under heteroskedasticity, resulting in significant power losses in the (wild bootstrap implementation of the) augmented Dickey–Fuller tests under the alternative. The proposed new lag selection criteria are shown to avoid this problem yet deliver unit root tests with almost identical finite sample properties as the corresponding tests based on conventional lag selection when the shocks are homoskedastic.     

Profile information matrix for nonlinear transformation models

For semiparametric models, interval estimation and hypothesis testing based on the information matrix for the full model is a challenge because of potentially unlimited dimension. Use of the profile information matrix for a small set of parameters of interest is an appealing alternative. Existing approaches for the estimation of the profile information matrix are either subject to the curse of dimensionality, or are ad-hoc and approximate and can be unstable and numerically inefficient. We propose a numerically stable and efficient algorithm that delivers an exact observed profile information matrix for regression coefficients for the class of Nonlinear Transformation Models [A. Tsodikov (2003) J R Statist Soc Ser B 65:759-774]. The algorithm deals with the curse of dimensionality and requires neither large matrix inverses nor explicit expressions for the profile surface.     

情报学素养在编辑工作中的作用

情报学素养是学术期刊编辑应具备的学术素养之一,情报意识贯穿整个编辑过程。本文试图通过对学术期刊编辑如何利用情报手段,掌握自己所需的情报,以帮助编辑了解学科前沿,正确地判断稿件的学术质量,使最有价值的信息以最快的速度进入传播领域。     

浅谈知识经济与大学生思想政治工作

知识经济的兴起,科学技术的飞速发展,在给人类带来巨大利益的同时,也带来了巨大的挑战。在高校,知识经济对大学生思想政治工作产生了重大的影响,即有积极的影响,也有负面的影响。为了做好知识经济时代的大学生思想政治工作,大学生思想政治工作者必须更新观念、改进工作方法,努力学习新的知识,进一步开创大学生思想政治工作新局面。     

基于智能代理的电子商务信息服务评价研究

随着计算机技术和信息技术的发展开始应用到诸多领域,现在最为热门的是智能代理技术在电子商务信息服务中的应用。本文首先从理论上阐述了智能代理技术的定义、特点、应用结构以及应用领域,归纳了其在电子商务信息服务中的应用层面和应用架构,然后重点对两个应用智能代理技术来提供信息服务的电子商务网站进行详尽的比较分析和研究,最后评价了电子商务信息服务中引入智能代理技术后出现的相关问题,并提出了部分改进意见。     

美国学前儿童使用技术的指导原则概述及启示

美国教育部、人类与健康服务部于2016年10月联合发布的《早期教育和教育技术政策简报》中指出了学前儿童使用技术的四条指导原则：使用得当的技术可以成为儿童学习的工具;应利用技术增加所有儿童获得学习的机会;技术可用于加强家庭、学前教育机构与儿童之间的关系;有效的学习取决于成人与儿童的互动或共同使用技术。指导原则的发布启示我们：应关注数字时代儿童的权利保护;加强从业人员的技术素养;加大对儿童技术使用的相关研究。     

论技术进步对个人使用的负面影响

With the rapid development of information communication technology in the 20th century, the technological advancement has put a test on copyright protection. Meanwhile, it has also brought constraints on the individual use of works and the personal involvement in social and cultural lives. In the context of digital information, it is highly necessary to update the copyright protection concepts and Copyright Law so as to ensure the rights of citizens to participate in the cultural life of the community freely and to keep a balance between copyright holders and their users