城市居家老人生活质量研究——以上海为例

本文针对城市居家老人的需要和特点,从评估城市居家老人生活质量的六个维度即经济状况与消费水平、居住条件与家庭设施、躯体健康与心理健康、社会支持、闲暇生活质量、生活满意度方面入手,深入开发了上海市老年人口状况与意愿跟踪调查数据资料,使用分等级加权评分法综合评估了城市居家老人生活质量以及分性别和年龄的老人生活质量。     

Program Evaluation and Causal Inference With High‐Dimensional Data

In this paper, we provide efficient estimators and honest confidence bands for a variety of treatment effects including local average (LATE) and local quantile treatment effects (LQTE) in data‐rich environments. We can handle very many control variables, endogenous receipt of treatment, heterogeneous treatment effects, and function‐valued outcomes. Our framework covers the special case of exogenous receipt of treatment, either conditional on controls or unconditionally as in randomized control trials. In the latter case, our approach produces efficient estimators and honest bands for (functional) average treatment effects (ATE) and quantile treatment effects (QTE). To make informative inference possible, we assume that key reduced‐form predictive relationships are approximately sparse. This assumption allows the use of regularization and selection methods to estimate those relations, and we provide methods for post‐regularization and post‐selection inference that are uniformly valid (honest) across a wide range of models. We show that a key ingredient enabling honest inference is the use of orthogonal or doubly robust moment conditions in estimating certain reduced‐form functional parameters. We illustrate the use of the proposed methods with an application to estimating the effect of 401(k) eligibility and participation on accumulated assets. The results on program evaluation are obtained as a consequence of more general results on honest inference in a general moment‐condition framework, which arises from structural equation models in econometrics. Here, too, the crucial ingredient is the use of orthogonal moment conditions, which can be constructed from the initial moment conditions. We provide results on honest inference for (function‐valued) parameters within this general framework where any high‐quality, machine learning methods (e.g., boosted trees, deep neural networks, random forest, and their aggregated and hybrid versions) can be used to learn the nonparametric/high‐dimensional components of the model. These include a number of supporting auxiliary results that are of major independent interest: namely, we (1) prove uniform validity of a multiplier bootstrap, (2) offer a uniformly valid functional delta method, and (3) provide results for sparsity‐based estimation of regression functions for function‐valued outcomes.     

拟均相固定床反应器的稳定性

分析了具有轴向扩散的拟均相固定床反应器的热稳定性,导出了这类反应器满足热稳定性所需要的条件。热稳定条件需要求解线性常微分方程,并根据解的特征来确定反应系统稳定与否而无需进行瞬态计算。     

我国的自然保护区现状简述

用较新的观点与数字,综述了建立自然保护区的目的和宗旨及我国自然保护区的特点与现状．     

我国城镇居民家庭纯收入和生活消费支出的典型相关分析

文章介绍了两组随机变量相关性的一种统计分析方法———典型相关分析(canonicalcorrelationanalysis),然后利用这种方法,借助SAS软件研究了我国31个省市自治区城镇居民家庭纯收入与生活消费支出的相关关系。     

Slack-variable models versus Scheffé's mixture models

Slack-variable models are compared against Scheffé's polynomial model for mixture experiments. The notion of model equivalence and the use of various diagnostic measures provide effective tools in making such comparisons, particularly when the experimental region is highly constrained. It is demonstrated that the choice of the best fitting model, through variable selection, depends on which mixture component is selected as a slack variable, and on the size of the fitted model. In addition, the equivalence of two well-known representations of a complete mixture model is shown to be valid. Two numerical examples are presented.     

双音节性质形容词ABAB式的重叠--兼与AABB式比较

形容词的重叠形式多样,表义丰富,极大地增强了语言的表现力,是汉语一种独特的构词方式,然而,目前理论界较少涉及性质形容词ABAB式重叠。通过比较,重点探讨分析性质形容词ABAB式重叠的语义条件、语法意义及句法表达功能。了解不同重叠形式的特点,有助于提高运用语言的能力,尤其对于学习汉语的外国人来说,则可避免出现不必要的失误。     

重视社区体育提高生活质量--无锡市社区体育现状的调查及研究

通过广泛的社会调查,笔者对无锡市社区体育现状进行了分析研究,证实了社区体育在提高现代生活质量中所起的重要作用以及在发展过程中所存在的问题,并提出了建议对策。     

弱弱联盟:加入WTO后我国中小企业的应对方略

加入WTO以后,面对世界跨国公司和大型企业纷纷结盟、市场竞争日益激烈的形势,处于弱势地位的我国中小企业更应该建立联盟。中小企业建立联盟的基本条件已相对具备。在中小企业之间建立联盟可望产生内、外部溢出效应。