Small Area Estimation Using Estimated Population Level Auxiliary Data

Unit level linear mixed models are often used in small area estimation (SAE), and the empirical best linear unbiased prediction (EBLUP) is widely used for the estimation of small area means under such models. However, EBLUP requires population level auxiliary data, atleast area specific aggregated values. Sometimes population level auxiliary data is either not available or not consistent with the survey data. We describe a SAE method that uses estimated population auxiliary information. Empirical results show that proposed method for SAE produces an efficient set of small area estimates.     

The Impact of Competitive Strategy and Supply Chain Strategy on Business Performance: The Role of Environmental Uncertainty*

This article investigates the relationships among competitive strategy, supply chain strategy, and business performance while examining the moderating effect of environmental uncertainty. A total of 604 questionnaires were collected from three cities in China, and the statistical results show significant moderating effects of external environment on the relationships among competitive strategy, supply chain strategy, and business performance. Firms that primarily focus on a differentiation strategy emphasize an agile supply chain strategy. Cost leaders are inclined to implement both lean and agile supply chain strategies, but their emphasis on agile strategy is significantly greater in a volatile environment than in a stable environment. The choice of supply chain strategy does not appear to be an “either‐or” decision and firms could adopt either a lean or an agile strategy, or both, depending on the environment. This article provides significant managerial implications for supply chain practitioners to co‐align supply chain strategy and competitive strategy with the environment to improve performance.     

论大学生运动员控制体重与饮食——以跆拳道为例

从分析大学生运动员赛前减控体重的方法入手,阐述了大学生运动员既能以"优势体重"参赛,又不危害身体健康和竞技水平的观点,通过查阅部分相关文献,提出了一套办法和推荐食谱以供参考。     

上证50股票价值的综合评价

采用主成分分析法对上证50的全部50家上市公司的股票价值进行综合评价。首先从这50家上市公司2005年度的财务报表数据中选取十一个重要指标作为基础,利用主成分分析法加以处理,合并为三个主成分,代入综合评价函数得到这50家上市公司股票的综合得分和综合排名;再对标准化的各因素指标的权重作进一步的讨论,最终得出这50家上市公司股票的综合排名。     

一种新型乙氧基化催化剂的合成及性能研究

本文研究 一种新型的催化剂-变白云母水合物，经酸碱处理后用于催化脂肪醇的乙氧基化反应。初步实验结果表明，化合物具有活性高、产物分子量分布窄、游离醇含量低等优良性能。     

一部弘扬中华文明的著作——读王炜民、郝建平著《中华文明概论》

《中华文明概论》以论为经,以史为纬,经纬交织,深刻阐发了中华文明的真谛。本书有四个鲜明的特色:重视宏观理论创新;对中华文明内涵的深度挖掘;对中华文明“和谐”精神内核的精辟阐述;文笔清新流畅,逻辑严整,高扬爱国主义的旗帜。     

Supplementing a survey with respondent Twitter data to measure e-cigarette information exposure

ABSTRACT

Social media data are increasingly used by researchers to gain insights on individuals’ behaviors and opinions. Platforms like Twitter provide access to individuals’ postings, networks of friends and followers, and the content to which they are exposed. This article presents the methods and results of an exploratory study to supplement survey data with respondents’ Twitter postings, networks of Twitter friends and followers, and information to which they were exposed about e-cigarettes. Twitter use is important to consider in e-cigarette research and other topics influenced by online information sharing and exposure. Further, Twitter metadata provide direct measures of user’s friends and followers as opposed to survey self-reports. We find that Twitter metadata provide similar information to survey questions on Twitter network size without inducing recall error or other measurement issues. Using sentiment coding and machine learning methods, we find Twitter can elucidate on topics difficult to measure via surveys such as online expressed opinions and network composition. We present and discuss models predicting whether respondents’ tweet positively about e-cigarettes using survey and Twitter data, finding the combined data to provide broader measures than either source alone.     

一类对角型退缩椭圆组弱解的全局正则性

本文证明了在控制增长及自然增长条件下，带A2类权函数的对角型拟线性方程组的全局正则性。     

Estimators for the Horvitz-Thompson Statistic Based on Some Posterior Distributions

The knowledge of first-order inclusion probabilities characterizing a sampling scheme is essential in design-based estimation of finite population totals. Sometimes the scheme is so complex that these probabilities cannot be computed exactly. Instead, both inclusion probabilities and corresponding sampling weights are simulated. One empirical Horvitz-Thompson estimator for a population total using simulation-based range-preserving estimates of sampling weights is obtained by applying the restricted maximum likelihood principle directly to each inclusion probability. The assumption of a prior distribution and the assessment of resulting posterior for a weight lead to two other estimators. One of them is the posterior mean estimator of the Horvitz-Thompson statistic. In a simulation involving Polish agricultural census data and a sequential fixed-cost sampling scheme, this estimator has attractive properties also from a frequentist point of view.     

基于心理账户理论的离合框架效应研究评述

通过回顾心理账户理论对离合框架效应的解释情况,发现已有文献对心理账户理论的支持情况并不理想。可能的原因是该理论的成立存在三个重要前提:不对广告价格信息重新加工;计算离框架各单品价格时,采用加法运算;加总离框架各单品价格时权重相等。消费者特点、商品价格特点以及价格表现形式能影响各个前提的成立。后续的研究,一方面要谨慎应用心理账户理论解释离合框架效应,另一方面要深入探讨已有文献中的争议和尚未研究的问题。