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Real pairwise completely positive matrices
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作者 ZHOU Anwa HE Jiayi 《运筹学学报(中英文)》 北大核心 2025年第3期160-178,共19页
In this paper,we introduce the real pairwise completely positive(RPCP)matrices with one of them is necessarily positive semidefinite while the other one is necessarily entrywise nonnegative,which has a real pairwise c... In this paper,we introduce the real pairwise completely positive(RPCP)matrices with one of them is necessarily positive semidefinite while the other one is necessarily entrywise nonnegative,which has a real pairwise completely positive(RPCP)decomposition.We study the properties of RPCP matrices and give some necessary and sufficient conditions for a matrix pair to be RPCP.First,we give an equivalent decomposition for the RPCP matrices,which is different from the RPCP-decomposition and show that the matrix pair(X,X)is RPCP if and only if X is completely positive.Besides,we also prove that the RPCP matrices checking problem is equivalent to the separable completion problem.A semidefinite algorithm is also proposed for detecting whether or not a matrix pair is RPCP.The asymptotic and finite convergence of the algorithm are also discussed.If it is RPCP,we can further give a RPCP-decomposition for it;if it is not,we can obtain a certificate for this. 展开更多
关键词 real pairwise completely positive matrices truncated moment problem semidefinite relaxation
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Incompressible Pairwise Incompressible Surfaces in Knot Complement
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作者 Youfa HAN Bingyu LUAN +1 位作者 Wenyue HOU Xintong WANG 《Journal of Mathematical Research with Applications》 2025年第6期835-849,共15页
We deal with the properties of incompressible and pairwise incompressible surfaces in knot complements through the application of relevant properties of almost simple topological graphs.We analyze the topological grap... We deal with the properties of incompressible and pairwise incompressible surfaces in knot complements through the application of relevant properties of almost simple topological graphs.We analyze the topological graph invariants associated with surfaces embedded in the complements of alternating and almost alternating knots.Specifically,we prove that the characteristic numbers of these graphs remain invariant under two fundamental transformations(R-move and S^(2)-move).Leveraging the interplay between characteristic numbers and Euler characteristics,and further connecting Euler characteristics to surface genus,we derive novel results regarding the genus of incompressible pairwise incompressible surfaces.Additionally,we establish a discriminant criterion to determine when such surfaces in knot complements admit genus zero. 展开更多
关键词 topological graph almost simple topological graphs knot complement incompressible surface pairwise incompressible surface
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An Active Safe Semi-Supervised Fuzzy Clustering with Pairwise Constraints Based on Cluster Boundary
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作者 Duong Tien Dung Ha Hai Nam +1 位作者 Nguyen Long Giang Luong Thi Hong Lan 《Computers, Materials & Continua》 2025年第12期5625-5642,共18页
Semi-supervised clustering techniques attempt to improve clustering accuracy by utilizing a limited number of labeled data for guidance.This method effectively integrates prior knowledge using pre-labeled data.While s... Semi-supervised clustering techniques attempt to improve clustering accuracy by utilizing a limited number of labeled data for guidance.This method effectively integrates prior knowledge using pre-labeled data.While semi-supervised fuzzy clustering(SSFC)methods leverage limited labeled data to enhance accuracy,they remain highly susceptible to inappropriate or mislabeled prior knowledge,especially in noisy or overlapping datasets where cluster boundaries are ambiguous.To enhance the effectiveness of clustering algorithms,it is essential to leverage labeled data while ensuring the safety of the previous knowledge.Existing solutions,such as the Trusted Safe Semi-Supervised Fuzzy Clustering Method(TS3FCM),struggle with random centroid initialization,fixed neighbor radius formulas,and handling outliers or noise at cluster overlaps.A new framework called Active Safe Semi-Supervised Fuzzy Clustering with Pairwise Constraints Based on Cluster Boundary(AS3FCPC)is proposed in this paper to deal with these problems.It does this by combining pairwise constraints and active learning.AS3FCPC uses active learning to query only the most informative data instances close to the cluster boundaries.It also uses pairwise constraints to enforce the cluster structure,which makes the system more accurate and robust.Extensive test results on diverse datasets,including challenging noisy and overlapping scenarios,demonstrate that AS3FCPC consistently achieves superior performance compared to state-of-the-art methods like TS3FCM and other baselines,especially when the data is noisy and overlaps.This significant improvement underscores AS3FCPC’s potential for reliable and accurate semisupervised fuzzy clustering in complex,real-world applications,particularly by effectively managing mislabeled data and ambiguous cluster boundaries. 展开更多
关键词 Active learning safe semi-supervised fuzzy clustering confidence weight boundary identification pairwise constraints
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Pairwise Reversible Data Hiding for Medical Images with Contrast Enhancement
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作者 Isaac Asare Boateng Lord Amoah Isogun Toluwalase Adewale 《Journal of Information Hiding and Privacy Protection》 2024年第1期1-19,共19页
Contrast enhancement in medical images has been vitalsince the prevalence of image representationsin healthcare.In this research,the PRDHMCE(pairwise reversible data hiding for medical images with contrast enhancement... Contrast enhancement in medical images has been vitalsince the prevalence of image representationsin healthcare.In this research,the PRDHMCE(pairwise reversible data hiding for medical images with contrast enhancement)algorithm is proposed as an automatic contrast enhancement(CE)method for medical images based on region ofinterest(ROI)and non-region of interest(NROI).The PRDHMCE algorithm strategically enhances the ROI aftersegmentation using histogram stretching and data embedding.An initial histogram evaluation compares histogrambins with their neighbours to select the bin with the maximum pixel count.The selected bin is set as the point forcontrast stretching with enhancement and secret data embedding in the ROI.The remaining data is embedded inthe NROIwhile reducing image distortions.Experimentalresultsshowthe effectiveness of PRDHMCE in optimallyimproving image contrast and increasing embedding capacity comparedwith existing methods based on qualitativeand objective metricssuch as peak signal-to-noise ratio(PSNR),structuralsimilarity index(SSIM),relative contrasterror(RCE),relative mean brightness error(RMBE)and mean opinion score(MOS).Additionally,PRDHMCErecovers medical images fully without data loss. 展开更多
关键词 Target histogram stretching pairwise histogram embedding reversible data hiding
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Pairwise马尔科夫模型下的势均衡多目标多伯努利滤波器 被引量:3
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作者 张光华 韩崇昭 +1 位作者 连峰 曾令豪 《自动化学报》 EI CSCD 北大核心 2017年第12期2100-2108,共9页
由于在实际应用中目标模型不一定满足隐马尔科夫模型(Hidden Markov model,HMM)隐含的马尔科夫假设和独立性假设条件,一种更为一般化的Pairwise马尔科夫模型(Pairwise Markov model,PMM)被提出.它放宽了HMM的结构性限制,可以有效地处理... 由于在实际应用中目标模型不一定满足隐马尔科夫模型(Hidden Markov model,HMM)隐含的马尔科夫假设和独立性假设条件,一种更为一般化的Pairwise马尔科夫模型(Pairwise Markov model,PMM)被提出.它放宽了HMM的结构性限制,可以有效地处理更为复杂的目标跟踪场景.本文针对杂波环境下的多目标跟踪问题,提出一种在PMM框架下的势均衡多目标多伯努利(Cardinality balanced multi-target multi-Bernoulli,CBMe MBer)滤波器,并给出它在线性高斯PMM条件下的高斯混合(Gaussian mixture,GM)实现.最后,采用一种满足HMM局部物理特性的线性高斯PMM,将本文所提算法与概率假设密度(Probability hypothesis density,PHD)滤波器进行比较.实验结果表明本文所提算法的跟踪性能优于PHD滤波器. 展开更多
关键词 隐马尔科夫模型 pairwise马尔科夫模型 多目标跟踪 随机有限集 多伯努利密度 高斯混合
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基于PairWise排序学习算法研究综述 被引量:6
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作者 熊李艳 陈晓霞 +1 位作者 钟茂生 黄晓辉 《科学技术与工程》 北大核心 2017年第21期184-190,共7页
Learning to Rank(L2R)技术是对搜索结果进行排序,是近几年的研究热点。现关于L2R中的PairWise方法进行研究分析,PairWise方法将排序问题转化为二元分类问题,其缺点是只考虑两篇文档的相对顺序,而不考虑文档出现在搜索结果列表中的位置... Learning to Rank(L2R)技术是对搜索结果进行排序,是近几年的研究热点。现关于L2R中的PairWise方法进行研究分析,PairWise方法将排序问题转化为二元分类问题,其缺点是只考虑两篇文档的相对顺序,而不考虑文档出现在搜索结果列表中的位置。另外,不同的查询拥有的文档对数目不同,结果会向拥有文档对较多的查询偏移。对常用的PairWise算法的损失函数及其求解方法、基本思想、算法框架、效用评价以及算法应用进行概括分析。 展开更多
关键词 pairwise 损失函数 优化方法
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基于pairwise的改进ranking算法 被引量:1
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作者 程凡 仲红 《计算机应用》 CSCD 北大核心 2011年第7期1740-1743,共4页
传统基于pairwise的ranking算法,学习后得到的模型在用NDCG这样的ranking标准评价时效果并不好,对此提出了一种新型ranking算法。该算法也是使用样本对作为训练数据,但定义了一个面向NDCG评估标准的目标函数。针对此目标函数非平滑、难... 传统基于pairwise的ranking算法,学习后得到的模型在用NDCG这样的ranking标准评价时效果并不好,对此提出了一种新型ranking算法。该算法也是使用样本对作为训练数据,但定义了一个面向NDCG评估标准的目标函数。针对此目标函数非平滑、难以直接优化的特点,提出使用割平面算法进行学习,不仅解决了上述问题,而且使算法迭代的次数不再依赖于训练样本对数。最后基于基准数据集的实验证明了算法的有效性。 展开更多
关键词 ranking算法 pairwise方法 支持向量机 NDCG 割平面算法
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基于Pairwise算法的人车事故中人伤影响因素分析 被引量:1
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作者 袁敏 侯林鹏 谭正平 《重庆理工大学学报(自然科学)》 CAS 北大核心 2020年第5期68-77,共10页
根据影响骑车人头部损伤的可能因素(汽车车速、电动车车速、碰撞角、骑车人面朝方向、地面附着系数、前置汽车发动机罩离地高度等9个因素)建立模型进行试验。经研究分析发现:在正向撞击过程中,骑车人头部HIC值受肢体作用汽车表面的影响... 根据影响骑车人头部损伤的可能因素(汽车车速、电动车车速、碰撞角、骑车人面朝方向、地面附着系数、前置汽车发动机罩离地高度等9个因素)建立模型进行试验。经研究分析发现:在正向撞击过程中,骑车人头部HIC值受肢体作用汽车表面的影响,此作用随车速的提升迅速减缓;汽车处于低速行驶撞击时(速度小于30 km/h),骑车人HIC值随汽车发动机罩离地高度逐次增加而减小;汽车处于高速行驶撞击时(速度大于等于30 km/h),骑车人HIC值随汽车发动机罩离地高度逐次增加而增大;当相对速度(即汽车前进方向上,电动车速度与汽车分速度之和)超过40 km/h时,骑车人头部有很大可能受到伤害或严重损伤。碰撞角为0°时骑车人头部伤害最重,碰撞角为90°时骑车人头部伤害最轻;骑车人头部与接触面作用时间越短,头部HIC值越大。 展开更多
关键词 事故再现 pairwise算法 极差法分析 碰撞角
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基于Pairwise算法的组合测试应用研究 被引量:1
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作者 郑根让 林正春 《电子技术与软件工程》 2022年第15期49-52,共4页
本文对基于Pairwise算法的组合测试常用实现方法进行了综述和比较分析。利用Pairwise算法思想对电商平台系统测试进行了需求分析及测试设计,使用PICT工具对电商平台进行组合测试实验,根据电商平台运行需求利用贪心算法对约束关系进行了... 本文对基于Pairwise算法的组合测试常用实现方法进行了综述和比较分析。利用Pairwise算法思想对电商平台系统测试进行了需求分析及测试设计,使用PICT工具对电商平台进行组合测试实验,根据电商平台运行需求利用贪心算法对约束关系进行了优化,进一步提高组合测试效能。为验证PICT在电商平台组合测试的有效性,对电商平台相关关联关系进行了仿真实验和实际测试,其在测试用例覆盖、测试生成速度和测试成本等方面具有一定优势。 展开更多
关键词 pairwise 组合测试 PICT工具
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Incompressible Pairwise Incompressible Surfaces in Knot Exteriors
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作者 韩友发 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期47-53,共7页
We discuss the properties of incompressible pairwise incompressible surfaces in a knot complement by using twist crossing number. Let K be a pretzel knot or rational knot that its twistindex is less than 6, and l... We discuss the properties of incompressible pairwise incompressible surfaces in a knot complement by using twist crossing number. Let K be a pretzel knot or rational knot that its twistindex is less than 6, and let F be an incompressible pairwise incompressible surface in S 3-K. Then F is a punctured sphere. 展开更多
关键词 incompressible pairwise incompressible surface twist crossing number pretzel knot puncture sphere rational knot
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基于Pairwise排序学习的因子分解推荐算法 被引量:1
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作者 周俊宇 戴月明 吴定会 《计算机应用与软件》 CSCD 2016年第6期255-259,共5页
针对基于内存的协同过滤推荐算法存在推荐列表排序效果不佳的问题,提出基于Pairwise排序学习的因子分解推荐算法(简称Pairwise-SVD推荐算法)。新算法将因子分解的预测结果作为排序学习算法的输入,把排序问题转化成分类问题使用排序学习... 针对基于内存的协同过滤推荐算法存在推荐列表排序效果不佳的问题,提出基于Pairwise排序学习的因子分解推荐算法(简称Pairwise-SVD推荐算法)。新算法将因子分解的预测结果作为排序学习算法的输入,把排序问题转化成分类问题使用排序学习理论进行排序产生推荐列表。实验结果表明相比基于内存的协同过滤推荐算法,Pairwise-SVD推荐算法的排序效果更佳。其在指标Kendall-tau上提高了近一倍,在指标MRR上提高了近30%,且在指标MAP上也有小幅提高。 展开更多
关键词 pairwise 因子分解 协同过滤 分类 排序学习
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On Pairwise Singular Sets and Pairwise Singular Maps
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作者 Rina Pankaj Verma Mamta Singh 《Journal of Mathematics and System Science》 2014年第4期261-268,共8页
In this paper we introduce the concept of pairwise singular sets and pairwise singular maps between pairwise locally compact and pairwise hausdorff spaces and study the properties of pairwise singular maps.
关键词 pairwise singular sets pairwise singular maps
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SOME LIMIT THEOREMS FOR SEQUENCES OF PAIRWISE NQD RANDOM VARIABLES 被引量:8
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作者 甘师信 陈平炎 《Acta Mathematica Scientia》 SCIE CSCD 2008年第2期269-281,共13页
In this article, the authors study some limit properties for sequences of pairwise NQD random variables, which are not necessarily identically distributed. They obtain Baum and Katz complete convergence and the strong... In this article, the authors study some limit properties for sequences of pairwise NQD random variables, which are not necessarily identically distributed. They obtain Baum and Katz complete convergence and the strong stability of Jamison's weighted sums for pairwise NQD random variables, which may have different distributions. Some wellknown results are improved and extended. 展开更多
关键词 pairwise NQD random variable sequence convergence in probability almost sure convergence complete convergence strong stability
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INCOMPRESSIBLE PAIRWISE INCOMPRESSIBLE SURFACES IN LINK COMPLEMENTS 被引量:4
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作者 韩友发 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1011-1019,共9页
The central subject of studying in this paper is incompressible pairwise incompressible surfaces in link complements. Let L be a non-split prime link and let F be an incompressible pairwise incompressible surface in S... The central subject of studying in this paper is incompressible pairwise incompressible surfaces in link complements. Let L be a non-split prime link and let F be an incompressible pairwise incompressible surface in S3 - L. We discuss the properties that the surface F intersects with 2-spheres in S3 - L. The intersection forms a topological graph consisting of a collection of circles and saddle-shaped discs. We introduce topological graphs and their moves (R-move and S2-move), and define the characteristic number of the topological graph for F∩S2±. The characteristic number is unchanged under the moves. In fact, the number is exactly the Euler Characteristic number of the surface when a graph satisfies some conditions. By these ways, we characterize the properties of incompressible pairwise incompressible surfaces in alternating (or almost alternating) link complements. We prove that the genus of the surface equals zero if the component number of F∩S2+(or F∩S2-) is less than five and the graph is simple for alternating or almost alternating links. Furthermore, one can prove that the genus of the surface is zero if #(F) ≤8. 展开更多
关键词 alternating link almost alternating link incompressible pairwise incompressible surface standard position GENUS
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An important property of entanglement: pairwise entanglement that can only be transferred by an entangled pair 被引量:4
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作者 惠小强 刘伍明 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期1858-1862,共5页
Based on the calculation of all the pairwise entanglements in the n (n ≤ 6)-qubit Heisenberg XX open chain with system impurity, we find an important result: pairwise entanglement can only be transferred by an ent... Based on the calculation of all the pairwise entanglements in the n (n ≤ 6)-qubit Heisenberg XX open chain with system impurity, we find an important result: pairwise entanglement can only be transferred by an entangled pair. The non-nearest pairwise entanglements will have the possibility to exist as long as there has been even number of qubits in their middle. This point indicates that we can obtain longer distance entanglement in a solid system. 展开更多
关键词 pairwise entanglement transfer of entanglement Heisenberg XX chain
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Some Remarks for Sequences of Pairwise NQD Random Variables 被引量:3
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作者 GAN Shixin CHEN Pingyan 《Wuhan University Journal of Natural Sciences》 CAS 2010年第6期467-470,共4页
We first obtain the Petrov theorem for pairwise NQD(negative quadrant dependent) random variables which may have different distributions.Some well-known results are improved and extended.Next,we give an example to c... We first obtain the Petrov theorem for pairwise NQD(negative quadrant dependent) random variables which may have different distributions.Some well-known results are improved and extended.Next,we give an example to clarify one of the important properties of sequences of pairwise NQD random variables,so that we can point out some mistakes that have appeared in recent published papers. 展开更多
关键词 pairwise NQD random variable sequence convergence in probability almost sure convergence Marcinkiewicz type weak law of law numbers
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A General Pairwise Key Predistribution Scheme for Wireless Sensor Networks 被引量:2
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作者 DING Xiaoyu LIU Zhiping SHAO Dingrong 《Wuhan University Journal of Natural Sciences》 CAS 2008年第6期744-748,共5页
This paper develops a general hypercube-based key predistribution scheme for establishing pairwise keys between sensor nodes using polynomials, which is parameterized by the dimension of hypercube and the Hamming dist... This paper develops a general hypercube-based key predistribution scheme for establishing pairwise keys between sensor nodes using polynomials, which is parameterized by the dimension of hypercube and the Hamming distance threshold variables. The scheme addresses the weaknesses of existing key predistribution schemes, which have either worse security or lower efficiency. It exhibits a nice property--when the Hamming distance between any two neighboring sensor nodes is less than the pre-defined threshold, the pairwise key can be established directly. Extensive performance and security analysis shows that by increasing Hamming distance threshold value, we can trade off the resilience against node capture attack for higher probability of direct pairwise key establishment, so as to save the energy consumption which is the most important issue for sensor networks. 展开更多
关键词 pairwise key establishment sensor networks hypercube-based key predistribution POLYNOMIAL Hamming distance
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Blind Image Quality Assessment by Pairwise Ranking Image Series 被引量:1
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作者 Li Xu Xiuhua Jiang 《China Communications》 SCIE CSCD 2023年第9期127-143,共17页
Image quality assessment(IQA)is constantly innovating,but there are still three types of stickers that have not been resolved:the“content sticker”-limitation of training set,the“annotation sticker”-subjective inst... Image quality assessment(IQA)is constantly innovating,but there are still three types of stickers that have not been resolved:the“content sticker”-limitation of training set,the“annotation sticker”-subjective instability in opinion scores and the“distortion sticker”-disordered distortion settings.In this paper,a No-Reference Image Quality Assessment(NR IQA)approach is proposed to deal with the problems.For“content sticker”,we introduce the idea of pairwise comparison and generate a largescale ranking set to pre-train the network;For“annotation sticker”,the absolute noise-containing subjective scores are transformed into ranking comparison results,and we design an indirect unsupervised regression based on EigenValue Decomposition(EVD);For“distortion sticker”,we propose a perception-based distortion classification method,which makes the distortion types clear and refined.Experiments have proved that our NR IQA approach Experiments show that the algorithm performs well and has good generalization ability.Furthermore,the proposed perception based distortion classification method would be able to provide insights on how the visual related studies may be developed and to broaden our understanding of human visual system. 展开更多
关键词 no reference image quality assessment distortion classification method pairwise preference network EVD-based unsupervised regression
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Strong Law of Large Numbers of Partial Sums for Pairwise NQD Sequences 被引量:1
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作者 Shuhe HU Xiaotao LIU +1 位作者 Xinghui WANG Xiaoqin LI 《Journal of Mathematical Research with Applications》 CSCD 2013年第1期111-116,共6页
By using the moment inequality, maximal inequality and the truncated method of random variables, we establish the strong law of large numbers of partial sums for pairwise NQD sequences, which extends the corresponding... By using the moment inequality, maximal inequality and the truncated method of random variables, we establish the strong law of large numbers of partial sums for pairwise NQD sequences, which extends the corresponding result of pairwise NQD random variables. 展开更多
关键词 pairwise NQD sequences strong law of large numbers.
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Pairwise Shared Ancestry in Random-Mating Constant-Size Populations 被引量:2
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作者 Philip M. Service 《Natural Science》 2022年第5期193-202,共10页
In a panmictic population of constant size N, random pairs of individuals will have a most recent shared ancestor who lived slightly more than 0.5 log<sub>2</sub>N generations previously, on average. The p... In a panmictic population of constant size N, random pairs of individuals will have a most recent shared ancestor who lived slightly more than 0.5 log<sub>2</sub>N generations previously, on average. The probability that a random pair of individuals will share at least one ancestor who lived 0.5 log<sub>2</sub>N generations ago, or more recently, is about 50%. Those individuals, if they do share an ancestor from that generation, would be cousins of degree (0.5 log<sub>2</sub>N) - 1. Shared ancestry from progressively earlier generations increases rapidly until there is universal pairwise shared ancestry. At that point, every individual has one or more ancestors in common with every other individual in the population, although different pairs may share different ancestors. Those ancestors lived approximately 0.7 log<sub>2</sub>N generations in the past, or more recently. Qualitatively, the ancestries of random pairs have about 50% similarity for ancestors who lived about 0.9 log<sub>2</sub>N generations before the present. That is, about half of the ancestors from that generation belonging to one member of the pair are present also in the genealogy of the other member. Qualitative pairwise similarity increases to more than 99% for ancestors who lived about 1.4 log<sub>2</sub>N generations in the past. Similar results apply to a metric of quantitative pairwise genealogical overlap. 展开更多
关键词 pairwise Shared Ancestry Genealogical Overlap Quantitative Ancestry Most Recent Common Ancestor Number of Cousins
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