Influence diagnostics in gamma ridge regression model

In this article, we proposed some influence diagnostics for the gamma regression model (GRM) and the gamma ridge regression model (GRRM). We assess the impact of influential observations on the GRM and GRRM estimates by extending the work of Pregibon [Logistic regression diagnostics. Ann Stat. 1981;9:705–724] and Walker and Birch [Influence measures in ridge regression. Technometrics. 1988;30:221–227]. Comparison of both models is made and demonstrated with the help of a simulation study and a real data set. We report some momentous results in detecting the influential observations and their effects on the GRM and GRRM estimates.     

社会学民族志的力量:重返早期社会研究的田野工作

自20世纪70年代以来，社会学民族志在田野工作和叙事复兴中与传统人文学汇聚，显著扩展了自己的学科边界。但是，这种扩展并没有解决社会学民族志在深度的经验发生和强烈的理论诉求之间遭遇的紧张。对于这种紧张，本文主张再访早期社会研究的田野，即19世纪末期到一战之前的若干典型研究，从中反思早期社会学田野工作是如何在“直接经验”的倾向中完成类型化，以及如何在这个经验感获得的同时改变对社会世界的道德想象。早期社会学的田野工作的力量之一不在于以规范的诉求压制经验感，而是以独特的情感结构连接经验的观察和道德理想的重生。由此，我们不仅需要反思诸如社会调查到社区研究这样的简单思路，更要重新理解理论史上所谓的“进步主义式”的道德本身。这一工作对重新认识早期社会研究和今天的社会学民族志都具有意义上的准备。     

Type I error rates from likelihood‐based repeated measures analyses of incomplete longitudinal data

The last observation carried forward (LOCF) approach is commonly utilized to handle missing values in the primary analysis of clinical trials. However, recent evidence suggests that likelihood‐based analyses developed under the missing at random (MAR) framework are sensible alternatives. The objective of this study was to assess the Type I error rates from a likelihood‐based MAR approach – mixed‐model repeated measures (MMRM) – compared with LOCF when estimating treatment contrasts for mean change from baseline to endpoint (Δ). Data emulating neuropsychiatric clinical trials were simulated in a 4 × 4 factorial arrangement of scenarios, using four patterns of mean changes over time and four strategies for deleting data to generate subject dropout via an MAR mechanism. In data with no dropout, estimates of Δ and SE_Δ from MMRM and LOCF were identical. In data with dropout, the Type I error rates (averaged across all scenarios) for MMRM and LOCF were 5.49% and 16.76%, respectively. In 11 of the 16 scenarios, the Type I error rate from MMRM was at least 1.00% closer to the expected rate of 5.00% than the corresponding rate from LOCF. In no scenario did LOCF yield a Type I error rate that was at least 1.00% closer to the expected rate than the corresponding rate from MMRM. The average estimate of SE_Δ from MMRM was greater in data with dropout than in complete data, whereas the average estimate of SE_Δ from LOCF was smaller in data with dropout than in complete data, suggesting that standard errors from MMRM better reflected the uncertainty in the data. The results from this investigation support those from previous studies, which found that MMRM provided reasonable control of Type I error even in the presence of MNAR missingness. No universally best approach to analysis of longitudinal data exists. However, likelihood‐based MAR approaches have been shown to perform well in a variety of situations and are a sensible alternative to the LOCF approach. MNAR methods can be used within a sensitivity analysis framework to test the potential presence and impact of MNAR data, thereby assessing robustness of results from an MAR method. Copyright © 2004 John Wiley & Sons, Ltd.     

论民国时期方志编修观的变革

民国时期 ,中国古代封建社会形成和相沿的传统的旧方志编修观被重新审视并受到批判 ,修志宗旨的创新、方志编修中进化史观的倡导、民史观的推行、综合文化观的阐扬 ,使民国时期的方志编修观发生变革 ,促进了民国新方志的编修 ,并为今日全新的方志编修观的构创和方志的编纂提供了借鉴与启迪。     

徐偃王在舟山史迹考

徐姓以国为姓。徐姓氏族原是岛夷族，崇拜鸟图腾。西周穆王时徐偃王因施仁政、不修武备而失国，逃战到舟山群岛。舟山至今仍有不少有关徐偃王的文物、史迹与传说。     

Local polynomial estimation of Poisson intensities in the presence of reporting delays

Summary.  The system for monitoring suicides in Hong Kong has considerable delays in reporting as the cause of death needs to be determined by a coroner's investigation. However, timely estimates of suicide rates are desirable to assist in the formulation of public health policies. This motivated us to develop a non-parametric procedure to estimate the intensity function of a Poisson process in the presence of reporting delays. We give closed form estimators of the Poisson intensity and the delay distribution, conduct simulation studies to evaluate the method proposed and derive their asymptotic properties. The method proposed is applied to estimate the intensity of suicide in Hong Kong.     

Bayesian analysis of outlier problems using divergence measures

A Bayesian approach is presented for detecting influential observations using general divergence measures on the posterior distributions. A sampling-based approach using a Gibbs or Metropolis-within-Gibbs method is used to compute the posterior divergence measures. Four specific measures are proposed, which convey the effects of a single observation or covariate on the posterior. The technique is applied to a generalized linear model with binary response data, an overdispersed model and a nonlinear model. An asymptotic approximation using Laplace method to obtain the posterior divergence is also briefly discussed.     

设计素描的四种基本功

设计素描作为学习设计的一门基础课程,通过观察方法、思维方式、表现形式、立体观念和细节刻画四个方面的介绍说明设计素描对于学习产品设计的重要性.     

清末民初桂西北壮汉瑶三族群际接触的 作用机制及当代启示 ——基于高甲布努瑶歌文本的研究

高甲布努瑶歌文本是瑶族用壮族古壮字传抄并以北部壮语方言为主要演述语言的民间口承文献。桂西北壮汉瑶三族交错杂居的分布特征为群际接触提供重要场域,也为民族交往交流交融奠定空间基础。受接触场景中政治、交通、经济与教育等各种因素的影响,清末民初桂西北壮汉瑶三族的群际接触分为积极与消极两种接触情况,其群际接触的中介变量包括群体间的依存关系、群际互动、群际情绪和认知因素等,这些中介变量所凝练出的历史经验对当前推动民族交流交融仍具有重要的启示意义。     

新编《镇海县志》序言

镇海自五代始即已建县,在县治的一千余年中,她的地名曾数度更改,她的土地更是有沧海桑田之变化。近代以来随着社会历史的发展,镇海又有了天翻地覆的变化。如今,镇海县境虽析为宁波市治下的镇海区和北仑区,但这部新编的最后一部县志似可为镇海县千年历史的全面而真实的记载和总结。