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关键词： 电子合同   书面合同   合同形式   功能等同法  

摘要： 合同形式直接影响合同的效力和证据地位。目前,关于电子合同形式的界定有不同观点,其中功能等同法是国际上立法实践中流行的做法,但国内学界对此法认识存在误区。功能等同法并没有直接规定电子合同具有与书面合同同等的效力,而是旨在确定能够令电子合同具有与书面合同同等效力的条件———功能等同。

关键词： discriminant analysis   regression trees   logistic regression   classification  

摘要： This study compares the classification accuracy of linear discriminant analysis (LDA), quadratic discriminant analysis QDA), logistic regression (LR), and classification and regression trees (CART) under a variety of data conditions. Past research has generally found comparable performance of LDA and LR, with relatively less research on QDA and virtually none on CART. This study uses Monte Carlo simulations to assess the cross-validated predictive accuracy of these methods, while manipulating such factors as predictor distribution, sample size, covariance matrix inequality, group separation, and group size ratio. The results indicate that QDA performs as well as or better than the other alternatives in virtually all conditions. Suggestions for practitioners are provided.

关键词： neurocysticercosis   seizures   epilepsy   acute symptomatic seizures  

摘要： Aims - To determine the etiologic role of neurocysticercosis (NC) in a hospital-based sample of epilepsies divided according to International League Against Epilepsy (ILAE) epidemiological criteria and number of seizures prior to presentation. Methods - A sample comprising 1026 consecutive patients with either definite seizures or epilepsy attending a Neurology Outpatient Service was divided into four subgroups: single seizure (n = 314), incident epilepsy (n = 127), prevalent epilepsy (n = 398) and recurrent acute symptomatic seizures (RASS) (n = 175). The etiologic contribution of NC to each of the subgroups was examined with imaging studies. Results - Neurocysticercosis was diagnosed on imaging studies in 34.6% of patients with seizure disorder of any type, 59.2% of those with a single seizure, 23.7% of those with recurrent seizure disorder, 92.0% of those with RASS, none of cases of incident epilepsy and 2.0% with prevalent epilepsy. A diagnosis of NC was significantly associated with single seizures (P < 0.001). Conclusion - Imaging abnormalities consistent with NC are frequently noted in persons presenting with a single seizure in neurologic care in NC-endemic countries like India. The probability of diagnosing NC diminishes with increasing numbers of seizures. Among samples of individuals with recurrent-unprovoked seizures, it is rare for imaging to demonstrate lesions of NC.

关键词： Unbiased Estimate   Exact Analytical Expression   Error Rate Estimate   Repeated Design   Small Sample Bias  

摘要： Background: Supervised learning for classification of cancer employs a set of design examples to learn how to discriminate between tumors. In practice it is crucial to confirm that the classifier is robust with good generalization performance to new examples, or at least that it performs better than random guessing. A suggested alternative is to obtain a confidence interval of the error rate using repeated design and test sets selected from available examples. However, it is known that even in the ideal situation of repeated designs and tests with completely novel samples in each cycle, a small test set size leads to a large bias in the estimate of the true variance between design sets. Therefore different methods for small sample performance estimation such as a recently proposed procedure called Repeated Random Sampling (RSS) is also expected to result in heavily biased estimates, which in turn translates into biased confidence intervals. Here we explore such biases and develop a refined algorithm called Repeated Independent Design and Test (RIDT). Results: Our simulations reveal that repeated designs and tests based on resampling in a fixed bag of samples yield a biased variance estimate. We also demonstrate that it is possible to obtain an improved variance estimate by means of a procedure that explicitly models how this bias depends on the number of samples used for testing. For the special case of repeated designs and tests using new samples for each design and test, we present an exact analytical expression for how the expected value of the bias decreases with the size of the test set. Conclusion: We show that via modeling and subsequent reduction of the small sample bias, it is possible to obtain an improved estimate of the variance of classifier performance between design sets. However, the uncertainty of the variance estimate is large in the simulations performed indicating that the method in its present form cannot be directly applied to small data sets.

关键词： 检验科信息管理系统   信息时代   检验信息   检验标本   管理模式   分析仪器   传统观念   处理信息   自动化   智能化   再表现   新技术   新方法   条形码   中和   运行   人工  

摘要： 在过去的十多年以来,信息时代的到来对检验科的运行和管理模式产生了重大的影响.由于自动化的发展,检验科不再表现为传统观念上的人工检验,已从智能化检验分析仪器中和条形码检验标本中获得了大量检验信息.为了检验科的生存和发展,必须要认识和寻找更好的处理信息的新技术和新方法,以能适应信息的时代的需要.

关键词： 钢筋保护层厚度   实体检验   钢筋移位  

摘要： 介绍了混凝土结构中钢筋保护层厚度的定义、作用以及结构验收中检测的意义、方法及检验过程中的问题。

关键词： 计算机网络技术   药品监督管理   抽查检验   数据处理分析   分析能力   药品检验   抽验工作   信息量  

摘要： 计算机网络技术的应用,以其传输速度快,信息量大,数据可共享,查询、统计和分析能力强等优点,在药品监督管理、药品检验的数据处理分析中发挥着巨大的作用。笔者依据我所情况,对以下几个问题作一介绍,以期为药品监督抽验工作提供有益参考。[第一段]

关键词： 药物相互作用   正交比较   多样本t检验  

摘要： 目的:探讨联合用药时药物相互作用的统计分析方法。方法:从一个实例着手,使用正交比较方法分析药物相互作用;并基于两样本比较t检验的基本原理,推导出进行多样本比较的t检验方法,并与正交比较的结果进行比较,说明分析思路与计算方法。结果:对于药物相互作用的分析,当观察结果为定量资料时,使用多样本t检验和正交比较都能完成药物相互作用的定量分析,并且能够明确回答是拮抗作用、相加作用还是增强作用;两种方法的分析结果是等价的。结论:采用多样本t检验或正交比较对药物相互作用研究的资料进行分析,结论更明确和可靠。

关键词： 核于   负宇称态   混合角   单胶子交换   单π介子交换  

摘要： 分别用单胶子交换和单π介子交换产生的夸克超精细相互作用,计算了最低质量负宇称核子态中的混合角.结果表明,两种交换之间的差别较大,混合角的实验数据更倾向于支持单胶子交换.

关键词： 合同成本   委托授权   企业   企业管理   合同执行  

摘要： 　　企业合同管理是相对政府合同管理而言,它是指企业通过建立必要的合同管理机构和完善合同管理制度,加强对本企业合同的订立和履行过程的管理,促进合同的全面执行,维护企业经济效益的活动.企业合同管理是企业经营管理的一项重要内容,也是企业依法经营、依法维护自身合法利益的一个重要方面.加强企业合同管理,对于提高合同水平,减少合同纠纷,进而促进企业加强和改善经营管理,提高经济效益,都具有十分重要的意义.由于《合同法》在合同管理上的过分简略,以致于许多企业的领导人在合同观念和合同意识上存在误区.本文是作者在长期担任企业法律顾问中的一点心得,希望对企业领导人有参考价值.……