Baarda数据探测法中的粗差误判分析

重点讨论了数据探测法中系统发生误警、漏检和误判的原因.探讨了3类错误与检验量间相关系数的函数关系,给出了在多个备选假设下3类错误发生概率的估计公式.以2个备选假设为例,通过仿真模拟计算了3类错误发生概率随统计量间相关系数的变化趋势,并证明当观测值统计量间强相关时,数据探测法发生误警的概率显著增加,从而导致最小可探测粗差理论值与实际值不符,降低了数据探测法的可信度及系统的可靠性.最后利用2个不同网形的算例验证了结论.     

基于中心线一侧打点数量异常判断选取准则

介绍了控制图的概念和3σ原理以及与控制图共生的2类错误,一是以真为假的第一类错误,一是以假为真的第二类错误。指出了控制图与假设检验一样,遵循"小概率事件不容易发生"这一统计基本原理。论述了控制图选用的显著性水平一般要比假设检验所选取的显著性水平小很多的原因。利用控制图中的落在控制限内中心线一侧打点数量这一视角,研究了位于控制限内n个样本打点中有k个落在中心线一侧相应质量系统异常判断准则的构建问题。分析出这k个点符合二项分布,给出了位于控制限内n个打点中至少有k个打点落在中心线一侧的概率计算公式。最后得到当n≤19各种样本情况的质量系统异常判断准则。     

单个均值检验中两类错误的成因及计算--兼与卢淑华教授商榷

在统计检验中,会犯两种类型的错误第一类错误与第二类错误.以单个均值的检验为例,分析了它们的成因和计算方法.可以认为,第一类错误由检验中的实际推断原理引起,第二类错误由检验中的逻辑谬误引起.第一类错误出现的概率为显著性水平α,即小概率事件发生的概率.第二类错误的计算方法是阐述的重点,也是在解决这一问题上与目前的方法不一致的地方.     

基于贝叶斯定理的异重流泥沙侵蚀经验式不确定性分析

异重流发生在水下环境,针对其泥沙侵蚀的准确实验数据获取较为困难,使得异重流泥沙侵蚀经验式不易得到高质量的验证和率定.本文应用基于贝叶斯定理的蒙特卡罗方法,结合现有连续入流式异重流实验数据,对异重流泥沙侵蚀经验式的经验系数(式(3)中A_3、N_1和N_2)进行概率统计研究.在不同A_3取值情况下,对N_1和N_2进行了采样和频次统计,有结论:1)当系数A_3=4～7时,均存在概率最大N_1-N_2组合(在N_1-N_2平面上,以该组N_1-N_2值为圆心,0. 3为半径的圆内,样本频次最高),使得泥沙侵蚀计算值和实测值拟合较好(相关系数达到0. 25～0. 28;原E_s93的相关系数仅为0. 19); 2)当A_3由小变大时,占总样本数25%、50%、75%、95%的N_1-N_2样本区间范围先变小、后变大;在A_3=4时,上述区间范围最小.这意味着,若实测数据增加或存在误差时,应用A_3=4和其对应的概率最大N_1-N_2值的经验式不确定性相对较小.     

逆抽样条件下风险差的检验

建立了不同的统计量对逆抽样条件下病例对照组实验中的风险差进行检验.这些统计量分别是Wald统计量,Score统计量和似然比统计量.然后采用Fisher-Score的方法求解感兴趣参数的方差.采用近似的方法计算各统计量条件下犯第1类错误的概率和功效.多数情况下,Score统计量比较好,特别是针对感兴趣的样本量小于30的条件下,Score统计量犯第1类错误的概率能控制在置信水平以下.     

一种相依极小p值统计量概率分布的近似计算方法

极小p值统计量常用于多重检验问题,其显著性在各个检验不独立的情形下计算复杂度过高.在单个假设的检验统计量联合服从多元正态分布,且检验统计量之间非负相关的假设下,检验统计量之间的相关系数的均值可以作为检验统计量相关性的度量.基于这个度量给出了一个计算极小p值统计量的分布函数的近似方法.模拟结果表明该方法计算简便,具有较高的逼近精度.     

基于自适应模型的数据库入侵检测方法

提出了一种基于自适应模型数据库入侵检测方法(ASIDS).该方法基于矩阵和最小支持度函数的AprioriZ关联算法,依据在训练和自适应入侵检测阶段产生数据库的操作特征,用户根据实际需求动态调整最小支持度函数的值,更高效挖掘操作特征.结合层次聚类算法产生动态规则库,通过计算待检测数据操作特征与规则库中聚类的距离是否超过聚类间最大距离来判断异常,以避免已有检测系统中判断"边界尖锐"问题,并实时把正常操作特征归入动态规则库,通过对报警信息的关联分析降低误警率.实验结果表明,ASIDS能够实时地进行入侵检测,具有很高的检测率和较低的误警率.     

略谈假设检验第二类错误的概率

文章以单个正态总体关于总体期望和方差的假设检验为例,具体分析利用备择假设中的某个特定参数值计算第二类错误的概率的方法,并讨论影响第二类错误的概率大小的因素.     

控制图犯第Ⅰ/Ⅱ类错误分析

控制图是目前我国正在推广并实施的质量管理的有效工具，它是统计推断的图上作业法。本文运用数理统计方法分析了控制图犯第Ⅰ/Ⅱ类错误的概率,指出了控制图犯第Ⅰ类错误的概率罗小,而犯第Ⅱ类错误的概率较大.分析了影响控制图犯第Ⅱ类错误的因素及其影响.最终给出了减少犯第Ⅱ类错误的方法及其理论依据.     

基于信息融合的图像分段检测

基于鲁棒控制理论,在视觉信息与机械运动信息的有机融合方面采用了多信息分布检测控制的信息融合方法;在理论上证明了各传感器的决策值经过与或逻辑表决融合后,可以使系统的误警概率减小,检测概率增大,并通过实验验证了上述理论的正确性.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the