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两组率同为100%或0%时率差置信区间估计的SAS实现 被引量:1
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作者 黄耀华 唐欣然 +1 位作者 段重阳 陈平雁 《中国卫生统计》 CSCD 北大核心 2017年第1期11-14,共4页
目的通过SAS编程实现两组事件发生率均为0%或100%时率差置信区间的估计。方法针对事件发生率均为100%或0%时率差置信区间的估计问题,采用SAS9.4编程,使置信区间估计的Miettinen Nurminen法、Newcombe-Wilson法及校正New combe-Wilson法... 目的通过SAS编程实现两组事件发生率均为0%或100%时率差置信区间的估计。方法针对事件发生率均为100%或0%时率差置信区间的估计问题,采用SAS9.4编程,使置信区间估计的Miettinen Nurminen法、Newcombe-Wilson法及校正New combe-Wilson法等三种方法得以实现,并通过实例进行说明。结果所编程序实现了三种方法的置信区间估计,便于专业和非专业人员使用。实例中两组样本量分别为59,56,结果两组事件发生率均为100%,三种方法的95%置信区间:Miettinen Nurminen法为[-6.16%,6.47%];Newcombe法为[-6.11%,6.42%];校正Newcombe法为[-7.62%,8.00%]。结论本文所提供的SAS宏程序可以简便地实现两组事件发生率均为0%或100%时三种常用的率差置信区间的估计方法。 展开更多
关键词 置信区间 SAS宏程序 Newcombe法 Miettinen Nurminen法
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基于置信熵差的冲突证据融合方法 被引量:1
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作者 许石君 侯毅 +2 位作者 邓新蒲 陈沛铂 周石琳 《智能计算机与应用》 2023年第1期19-24,30,共7页
在证据理论中,加权平均是解决冲突证据融合的有效方法。然而,如何合理地确定证据权重是一个值得研究的问题,现有的一些方法利用置信熵自身来确定证据权重,在一定程度上解决了冲突问题,但当冲突证据置信熵值大于或等于正常证据时,系统将... 在证据理论中,加权平均是解决冲突证据融合的有效方法。然而,如何合理地确定证据权重是一个值得研究的问题,现有的一些方法利用置信熵自身来确定证据权重,在一定程度上解决了冲突问题,但当冲突证据置信熵值大于或等于正常证据时,系统将赋予冲突证据同等甚至更大的权重值,导致冲突得不到有效处理。本文提出基于置信熵差的冲突证据融合方法,利用证据内对应焦元的邓熵值差度量证据之间的差异,从而合理地确定证据权重值。算例结果表明,该方法能够克服现有方法的不足,赋予冲突证据更小的权重值,且具有更高的正确目标可信度。 展开更多
关键词 冲突证据 加权平均 置信 证据权重
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基于特征融合的电磁信号对抗样本检测方法
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作者 徐东伟 蒋斌 +4 位作者 陈嘉峻 宣琦 王巍 赵文红 杨小牛 《电波科学学报》 CSCD 北大核心 2024年第5期926-933,共8页
针对电磁信号调制识别智能模型容易受到对抗样本攻击的问题,提出了一种基于特征融合的电磁信号对抗样本检测方法。该方法首先通过变分模态分解对测试样本进行去噪得到去噪后的电磁信号样本,然后分别将去噪前后的电磁信号样本输入到神经... 针对电磁信号调制识别智能模型容易受到对抗样本攻击的问题,提出了一种基于特征融合的电磁信号对抗样本检测方法。该方法首先通过变分模态分解对测试样本进行去噪得到去噪后的电磁信号样本,然后分别将去噪前后的电磁信号样本输入到神经网络模型中,接着计算去噪前后模型输出向量的余弦相似性值和置信度差值,最后将两个特征进行融合,输入到一个神经网络模型中进行检测。与基线方法相比,该方法在实验中取得了更高的检测成功率。本文方法具有时间复杂度低、易于实现的优点,为电磁信号调制识别智能模型提供了一种新颖的对抗样本检测方法。 展开更多
关键词 电磁信号调制识别 对抗样本检测 特征融合 余弦相似性 置信
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一种改进的正负关联规则挖掘算法 被引量:9
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作者 陈宁军 高志年 《计算机科学》 CSCD 北大核心 2011年第12期191-193,212,共4页
针对传统正负关联规则挖掘算法需要多次扫描数据库并且生成大量候选频繁项集的问题,在对比目前相关研究成果的基础上,提出了一种改进的正负关联规则挖掘算法,它通过两次数据扫描完成对正负关联规则的挖掘,对最大频繁项集的挖掘算法做了... 针对传统正负关联规则挖掘算法需要多次扫描数据库并且生成大量候选频繁项集的问题,在对比目前相关研究成果的基础上,提出了一种改进的正负关联规则挖掘算法,它通过两次数据扫描完成对正负关联规则的挖掘,对最大频繁项集的挖掘算法做了改进,有效提高了算法效率,同时对置信度标准做了改进。基于某真实事务集的实验表明,算法提高了规则挖掘的质量和有效性。 展开更多
关键词 正负关联规则 关联规则挖掘 最大频繁项集 置信差
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A Novel Low Density Parity Check Coded Differential Amplitude and Pulse Position Modulation Free-Space Optical System for Turbulent Channel 被引量:3
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作者 Yin Liang Hua Zhang +2 位作者 Limin Chen Xiaoping Liu Xuehong Lin 《China Communications》 SCIE CSCD 2017年第3期198-206,共9页
Based on the proposed partly equidifferent mapping and its specific Differential Amplitude and Pulse Position Modulation(DAPPM) demodulation, a modified FSO scheme for turbulent channel is designed and analyzed. The n... Based on the proposed partly equidifferent mapping and its specific Differential Amplitude and Pulse Position Modulation(DAPPM) demodulation, a modified FSO scheme for turbulent channel is designed and analyzed. The novel Low Density Parity Check(LDPC) coded 4×4 and 4×8 DAPPM Free-Space Optical communication(FSO) system is constructed. The Monte Carlo simulation results show approximately 2d B transmit power reduction against classical LDPC-DAPPM at the identical Bit-Error-Rate in strong turbulent channel. The proposed partly equidifferent mapping is compatible with other modulations, so it enables widespread adoption in other coded FSO systems. 展开更多
关键词 DAPPM LDPC partly equidifferent mapping FSO turbulent
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A New Approach to Simulate Positional Error of Line Segment in GIS
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作者 ZHANG Lei DENG Min CHEN Xiaoyong 《Geo-Spatial Information Science》 2006年第2期142-146,共5页
To determine the distribution of positional error of a line segment, Monte Carlo approach is applied to simulate the probability density function of a line segment with the assumption that the error of endpoints in a ... To determine the distribution of positional error of a line segment, Monte Carlo approach is applied to simulate the probability density function of a line segment with the assumption that the error of endpoints in a line segment follows a two-dimensional normal distribution. For such purpose, a stochastic generator used for uncertain endpoints with the two-dimensional normal distribution is presented. This forms the basis of the generation of random line segment for the simulation of the error model of a whole line segment. The error models cover the cases where two endpoints are either independent or dependent to each other, also including a special case that the distance between two random endpoints in a line segment is close enough. 展开更多
关键词 positional error Monte Carlo simulation line segment stochastic point generator
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Quadratic Radical Function Better Than Fisher z Transformation 被引量:2
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作者 杨正瓴 段志峰 +3 位作者 王晶晶 王腾 宋延文 张军 《Transactions of Tianjin University》 EI CAS 2013年第5期381-384,共4页
A new explicit quadratic radical function is found by numerical experiments,which is simpler and has only 70.778%of the maximal distance error compared with the Fisher z transformation.Furthermore,a piecewise function... A new explicit quadratic radical function is found by numerical experiments,which is simpler and has only 70.778%of the maximal distance error compared with the Fisher z transformation.Furthermore,a piecewise function is constructed for the standard normal distribution:if the independent variable falls in the interval(-1.519,1.519),the proposed function is employed;otherwise,the Fisher z transformation is used.Compared with the Fisher z transformation,this piecewise function has only 38.206%of the total error.The new function is more exact to estimate the confidence intervals of Pearson product moment correlation coefficient and Dickinson best weights for the linear combination of forecasts. 展开更多
关键词 normal distribution cumulative distribution function error function confidence interval correlation coefficient combination of forecasts
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Comparative Analysis of EEG Signals Based on Complexity Measure
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作者 ZHU Jia-fu HE Wei 《Chinese Journal of Biomedical Engineering(English Edition)》 2009年第4期144-148,170,共6页
The aim of this study is to identify the functions and states of the brains according to the values of the complexity measure of the EEG signals. The EEG signals of 30 normal samples and 30 patient samples are collect... The aim of this study is to identify the functions and states of the brains according to the values of the complexity measure of the EEG signals. The EEG signals of 30 normal samples and 30 patient samples are collected. Based on the preprocessing for the raw data, a computational program for complexity measure is compiled and the complexity measures of all samples are calculated. The mean value and standard error of complexity measure of control group is as 0.33 and 0.10, and the normal group is as 0.53 and 0.08. When the confidence degree is 0.05, the confidence interval of the normal population mean of complexity measures for the control group is (0.2871,0.3652), and (0.4944,0.5552) for the normal group. The statistic results show that the normal samples and patient samples can be clearly distinguished by the value of measures. In clinical medicine, the results can be used to be a reference to evaluate the function or state, to diagnose disease, to monitor the rehabilitation progress of the brain. 展开更多
关键词 EEG signal nonlinear dynamics Kolmogorov complexity comparative analysis
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Investigation of Red Meat Production in Turkey by ANOM Test
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作者 Senol Celik 《Journal of Agricultural Science and Technology(A)》 2017年第3期209-213,共5页
When comparing more than two groups means, the analysis of means (ANOM) can be used as an alternative to the one-way analysis of variance (ANOVA) F test. The ANOM provides a "confidence interval type of approach... When comparing more than two groups means, the analysis of means (ANOM) can be used as an alternative to the one-way analysis of variance (ANOVA) F test. The ANOM provides a "confidence interval type of approach" that allows it to determine which, if any, of the x groups has a significantly different mean from the overall average of all the group means combined. The aim of this study was to show the application of a statistical technique (ANOM), mostly used by agriculture, to determine differences between red meat production by period in Turkey. The production quantities of goat meat, mutton, buffalo meat and beef between the years 2010 and 2016 according to the period were taken from Turkish Statistical Institute (TSI). As a result, the difference between meat productions was found to be significant. 展开更多
关键词 ANOM test meat production period.
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GENERALIZED p-VALUES AND GENERALIZED CONFIDENCE INTERVALS FOR VARIANCE COMPONENTS IN GENERAL RANDOM EFFECT MODEL WITH BALANCED DATA 被引量:9
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作者 Rendao YE Songgui WANG 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2007年第4期572-584,共13页
Various random models with balanced data that are relevant for analyzing practical test data are described, along with several hypothesis testing and interval estimation problems concerning variance components. In thi... Various random models with balanced data that are relevant for analyzing practical test data are described, along with several hypothesis testing and interval estimation problems concerning variance components. In this paper, we mainly consider these problems in general random effect model with balanced data. Exact tests and confidence intervals for a single variance component corresponding to random effect are developed by using generalized p-values and generalized confidence intervals. The resulting procedures are easy to compute and are applicable to small samples. Exact tests and confidence intervals are also established for comparing the random-effects variance components and the sum of random-effects variance components in two independent general random effect models with balanced data. Furthermore, we investigate the statistical properties of the resulting tests. Finally, some simulation results on the type Ⅰ error probability and power of the proposed test are reported. The simulation results indicate that exact test is extremely satisfactory for controlling type Ⅰ error probability. 展开更多
关键词 Generalized confidence interval generalized p-value variance component.
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CONSTRUCTION AND COMPARISONS OF SIMULTANEOUS CONFIDENCE INTERVALS FOR THE MEAN DIFFERENCE OF MULTIVARIATE NORMAL DISTRIBUTIONS
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作者 Xianhua MENG·Jinglong WANG·Xianyi WU School of Finance and Statistics,East China Normal University,Shanghai 200241,China. 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2010年第2期303-314,共12页
In this paper,Scheffé and Simplified Scheffé simultaneous confidence intervals are firstconstructed for mean difference of several multivariate normal distributions.Then the authors theoreticallyprove that w... In this paper,Scheffé and Simplified Scheffé simultaneous confidence intervals are firstconstructed for mean difference of several multivariate normal distributions.Then the authors theoreticallyprove that when there are only two populations,Bonferroni bounds and Simplified Scheffébounds are the same and they are shorter than Scheffé bounds for p10.In the case for 3k10and 2p10,there exists n(p,k)such that Bonferroni method is better than Simplified Schefféprocedure for nn(p,k),otherwise Simplified Scheffé procedure is better.Finally,the authors findout that neither of Scheffé critical values nor Simplified Scheffé critical values are always larger thananother through numerical calculation. 展开更多
关键词 Bonferroni simultaneous confidence interval multiple comparison Scheff@ simultaneousconfidence interval simplified Scheffé simultaneous confidence interval.
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Detecting Difference Between Coefficients in Linear Model Using Jackknife Empirical Likelihood
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作者 WU Xinqi ZHANG Qingzhao ZHANG Sanguo 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2016年第2期542-556,共15页
Empirical likelihood has been found very useful in many different occasions. It usually runs into serious computational difficulties while jackknife empirical likelihood (JEL) is shown to be effective when applied t... Empirical likelihood has been found very useful in many different occasions. It usually runs into serious computational difficulties while jackknife empirical likelihood (JEL) is shown to be effective when applied to some complicated statistics. In this paper, to test the difference between coefficients of two linear regression models, the authors apply JEL to construct the confidence regions. Based on the 3EL ratio test, a version of Wilks' theorem is developed. Furthermore, to improve the coverage accuracy of confidence regions, a Bartlett correction is applied. Simulation studies are carried out to show the effectiveness of the proposed method in aspects of coverage accuracy. A real data set is analyzed with the proposed method as an example. 展开更多
关键词 Bartlett correction coverage accuracy Jackknife empirical likelihood linear regression model.
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