Parameter estimation in nonlinear regression models 1

Fisher information contained in record values, inter-record times and their concomitants from a sample of fixed size is derived in general and explicit expressions are deduced for some specific known bivariate classes of distributions. A comparison between fixed sampling and inverse sampling schemes with equal number of records and concomitants is also carried out. We also consider parameter estimation based on bivariate records and a small simulation study is done.     

基于公文筐测验的商业银行高层管理人员选拔研究——以商业银行高级人力资源经理岗位为例

在采用文献法、访谈法和问卷法确定了银行高级人力资源管理者胜任力模型的基础上,设计和编制了适用于商业银行人力资源经理岗位的公文筐测验。研究结果表明,公文筐测验具有较高的信度和效度,可以在商业银行高层管理人员选拔中使用,但公文筐测验必须根据具体岗位来设计题目才能保证选拔的效果。     

Controlling the familywise error rate with plug-in estimator for the proportion of true null hypotheses

Summary.  Estimation of the number or proportion of true null hypotheses in multiple-testing problems has become an interesting area of research. The first important work in this field was performed by Schweder and Spjøtvoll. Among others, they proposed to use plug-in estimates for the proportion of true null hypotheses in multiple-test procedures to improve the power. We investigate the problem of controlling the familywise error rate FWER when such estimators are used as plug-in estimators in single-step or step-down multiple-test procedures. First we investigate the case of independent p -values under the null hypotheses and show that a suitable choice of plug-in estimates leads to control of FWER in single-step procedures. We also investigate the power and study the asymptotic behaviour of the number of false rejections. Although step-down procedures are more difficult to handle we briefly consider a possible solution to this problem. Anyhow, plug-in step-down procedures are not recommended here. For dependent p -values we derive a condition for asymptotic control of FWER and provide some simulations with respect to FWER and power for various models and hypotheses.     

阅读理解测试的变量研究

本文通过对实验素材和结果的定量分析 ,探讨了可读性、题材、测试题型 (自变量 )与测试结果 (因变量 )之间的相关关系。证明了 :1.不同的题材具有不同的区分能力 ;2 .不同的题型是造成分数差异的主要因素。指出 :在被试的能力范围内 ,可读性对测试结果的影响 ,并不如国外 36项研究所表明的那么明显。含多种题材和题型的阅读理解测试 ,更能有效地反映被试在阅读理解过程中各个层次的能力。     

Modified Wald statistics for generalized linear models

Summary: Wald statistics in generalized linear models are asymptotically ² distributed. The asymptotic chi–squared law of the corresponding quadratic form shows disadvantages with respect to the approximation of the finite–sample distribution. It is shown by means of a comprehensive simulation study that improvements can be achieved by applying simple finite–sample size approximations to the distribution of the quadratic form in generalized linear models. These approximations are based on a ² distribution with an estimated degree of freedom that generalizes an approach by Patnaik and Pearson. Simulation studies confirm that nominal level is maintained with higher accuracy compared to the Wald statistics.     

Parametric Modeling for Survival with Competing Risks and Masked Failure Causes

We consider a life testing situation in which systems are subject to failure from independent competing risks. Following a failure, immediate (stage-1) procedures are used in an attempt to reach a definitive diagnosis. If these procedures fail to result in a diagnosis, this phenomenon is called masking. Stage-2 procedures, such as failure analysis or autopsy, provide definitive diagnosis for a sample of the masked cases. We show how stage-1 and stage-2 information can be combined to provide statistical inference about (a) survival functions of the individual risks, (b) the proportions of failures associated with individual risks and (c) probability, for a specified masked case, that each of the masked competing risks is responsible for the failure. Our development is based on parametric distributional assumptions and the special case for which the failure times for the competing risks have a Weibull distribution is discussed in detail.     

隋代以前两淮盐业经济考述

隋代以前的两淮盐业,学术界少有述及。两淮盐业至少在春秋战国时即已出现,两汉时获得了大的发展。魏晋南北朝时期虽封建政权更迭频仍,两淮地区屡遭战乱,盐政、盐制也不断变化,但因人们生活需要和国家对盐业的重视,盐业经济仍能曲折性地向前发展。这对"苏北在隋唐以前,经济文化发展水平高于苏南",起了不可低估的作用。     

The Incremental Group Testing Model for Gap Closing in Sequencing Long Molecules

In this paper, we propose the incremental group testing model for the gap closing problem, which assumes that we can tell the difference between the outcome of testing a subset S, and the outcome of testing S {x}. We also give improvements over currently best results in literature for some other models.     

先秦文学风格观对刘勰“风骨论”的影响

以<诗经>、<尚书>、<国语>、<左传>为代表的诗经时代文学风格观念与"风骨论"有着渊源关系,先秦儒家与道家的文学风格观都不同程度地对"风骨论"产生过影响,先秦诸子和魏晋玄学的风格观对"风骨论"的形成具有更为直接的影响.正是刘勰从"宗经"、"征圣"的复古立场出发,提出了古代文艺理论中属于内容方面的重要范畴--风骨论.     

Perceived Risks from Radiation and Nuclear Testing Near Semipalatinsk, Kazakhstan: A Comparison Between Physicians, Scientists, and the Public

Determining the difference in perception of risk between experts, or more educated professionals, and laypeople is important so that a potential hazard can be effectively communicated to the public. Many surveys have been conducted to better understand the difference between expert and public opinions, and often laypeople exhibit higher perceptions of risk to hazards in comparison to experts. This is especially true when health risk is due to radiation, nuclear power, and nuclear waste. This article focuses on one section of a risk perception survey given to two groups of individuals with a more specialized education (scientists and physicians) and laypeople (villagers) in the Semipalatinsk region of Kazakhstan. All of these groups live near the former Soviet nuclear test site. Originally, it was expected that the scientists and physicians would have similar perceptions of radiation risk, while the public perceptions would be higher, but this was not always the case. For example, when perceptions of risk pertain to the health impacts of nuclear testing or the dose-response nature of radiation exposure, the physicians tend to agree with the laypeople, not the scientists. The villagers are always the most risk-averse group, followed by the physicians and then the scientists. These differences are likely due to different frames of reference for each of the populations.