How to be Resilient? Local Philanthropy as a Collective Response to Natural Disasters

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - When communities are struck by natural disasters, human service organizations play an important role in supplementing...     

Joint modelling of longitudinal binary data and survival data

The medical costs in an ageing society substantially increase when the incidences of chronic diseases, disabilities and inability to live independently are high. Healthy lifestyles not only affect elderly individuals but also influence the entire community. When assessing treatment efficacy, survival and quality of life should be considered simultaneously. This paper proposes the joint likelihood approach for modelling survival and longitudinal binary covariates simultaneously. Because some unobservable information is present in the model, the Monte Carlo EM algorithm and Metropolis-Hastings algorithm are used to find the estimators. Monte Carlo simulations are performed to evaluate the performance of the proposed model based on the accuracy and precision of the estimates. Real data are used to demonstrate the feasibility of the proposed model.     

Propensity score prediction for electronic healthcare databases using super learner and high-dimensional propensity score methods

ABSTRACT

The optimal learner for prediction modeling varies depending on the underlying data-generating distribution. Super Learner (SL) is a generic ensemble learning algorithm that uses cross-validation to select among a ‘library’ of candidate prediction models. While SL has been widely studied in a number of settings, it has not been thoroughly evaluated in large electronic healthcare databases that are common in pharmacoepidemiology and comparative effectiveness research. In this study, we applied and evaluated the performance of SL in its ability to predict the propensity score (PS), the conditional probability of treatment assignment given baseline covariates, using three electronic healthcare databases. We considered a library of algorithms that consisted of both nonparametric and parametric models. We also proposed a novel strategy for prediction modeling that combines SL with the high-dimensional propensity score (hdPS) variable selection algorithm. Predictive performance was assessed using three metrics: the negative log-likelihood, area under the curve (AUC), and time complexity. Results showed that the best individual algorithm, in terms of predictive performance, varied across datasets. The SL was able to adapt to the given dataset and optimize predictive performance relative to any individual learner. Combining the SL with the hdPS was the most consistent prediction method and may be promising for PS estimation and prediction modeling in electronic healthcare databases.     

学区在教育变革中的作用

美国和加拿大对于学区在教育变革中的作用研究已有近40年的历史.关于学区在教育变革中的作用研究可划分为几个具有不同特点的时期,包括创新实施时期、高效学校范式时期、学校重构时期和基于标准的变革时期.综述列举了不同研究时期最重要的一些研究,并讨论了它们的研究特点和成果.在关于成功学区的案例研究的基础上,着重分析了学区在系统改进学生学习的过程中所面临的挑战、学区改进学生学习所采取的策略以及学区影响教学和学习质量的证据.同时,总结并讨论了12条促进学生学习的学区策略,提供了5个关于学区在教育变革中的作用的研究方向.     

Increasing Returns and Social Contagion in Cultural Industries

A formal definition of cultural industries is developed following four distinct features of cultural goods: (a) oversupply, (b) quality uncertainty, (c) network effects and (d) demand reversal. Drawing on economic and socio-psychological notions of ‘network’, increasing returns and social contagion effects are distinguished. Increasing returns may govern the adoption of standards when choices are binary, social contagion explains the diffusion of cultural goods when choices are multiple. Together, the four structural features delineating cultural industries account for curious competitive dynamics prevalent in cultural markets, such as the notorious 10 : 90 proportionality (under which 10% of cultural goods account for 90% of the market), causal ambiguity about the reasons for success, and the formation of fashions. Six managerial recommendations are advanced, focusing on a criticial circulation point triggering self-sustaining diffusion patterns. Finally ‘project-based enterprises’ and ‘network forms of governance’ are identified as the organizational forms most suited to the dynamics of the cultural markets.     

化工原理实验教学软件开发研究

使用“MicrosoftOfficeFrontPage”、“东方网页王”、“Java”、“主页秀3”等软件开发的《化工原理实验教学软件》每个教学单元包括文字、图片和影视三个部分,并都配有语音。该软件使用方便,内容丰富,并可以通过网络进行访问,几乎不受时空限制,极大地方便了化工原理实验课程的教与学。     

纪检监察派驻机构统一管理模式分析

由于纪检监察双重领导体制严重制约纪检监察派驻机构的监督成效,2004年中央纪委、监察部着手推动纪检监察派驻机构实行统一管理的体制改革.各地结合实际大胆探索,创造出"点派驻"、"片派驻"和"点面结合"等三种统一管理模式.三种模式各有其内容特点、体制优劣、实际功效和适用条件,异彩纷呈,不同程度地克服了旧体制的弊端.其中,"点面结合"模式出现最晚,但它既保留了"点派驻"管理模式的长处,又吸纳了"片派驻"管理模式的优点,有可能成为派驻机构统一管理改革的新方向.     

The Short-Term Impact of Involuntary Migration in China’s Three Gorges: A Prospective Study

The aim of this study is to measure the short-term impact of involuntary migration resulting from China’s Three Gorges Dam project on the 1.3 million persons being displaced. We focus on the social, economic, and mental and physical health impact using three sets of indicators. Using a prospective research design, we gathered information about these indicators from a sample of migrants first before they moved and then again after they moved. Changes in the migrants’ wellbeing during the period, when benchmarked to corresponding changes computed for a control group of non-migrants, are attributed to the impact of involuntary migration. Our results showed that although the displaced have enjoyed a relative gain in housing quality, most of the changes were in the negative direction and many of such negative changes were statistically significant.     

中国信用评估业的产业组织分析

从全球范围来看,信用评估业存在规模经济和范围经济,产品差异较大,存在进入壁垒,是一个垄断程度较高、市场运行良好的行业。中国的信用评估业远未实现规模经济,存在过度竞争。要尽快发展我国的信用评估业,就要提高行业进入壁垒,促进行业内现有评估机构的兼并与联合,但同时又要防止垄断的产生。     

Adaptive designs for IVPT data with mixed scaled average bioequivalence

In vitro permeation tests (IVPT) offer accurate and cost-effective development pathways for locally acting drugs, such as topical dermatological products. For assessment of bioequivalence, the FDA draft guidance on generic acyclovir 5% cream introduces a new experimental design, namely the single-dose, multiple-replicate per treatment group design, as IVPT pivotal study design. We examine the statistical properties of its hypothesis testing method—namely the mixed scaled average bioequivalence (MSABE). Meanwhile, some adaptive design features in clinical trials can help researchers make a decision earlier with fewer subjects or boost power, saving resources, while controlling the impact on family-wise error rate. Therefore, we incorporate MSABE in an adaptive design combining the group sequential design and sample size re-estimation. Simulation studies are conducted to study the passing rates of the proposed methods—both within and outside the average bioequivalence limits. We further consider modifications to the adaptive designs applied for IVPT BE trials, such as Bonferroni's adjustment and conditional power function. Finally, a case study with real data demonstrates the advantages of such adaptive methods.