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Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence 被引量:1
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作者 Jiazhen ZHAO Shengping HE +2 位作者 Ke FAN Huijun WANG Fei LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1465-1482,共18页
Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Ar... Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. Here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions scenario.Thereafter, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained). 展开更多
关键词 wintertime newly formed Arctic sea ice model democracy model weighting scheme model performance model independence
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Independence Polynomials and the Merrifield-Simmons Index of Mono-Layer Cylindrical Grid Graphs
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作者 JI Lin-xing ZHANG Ke HU Wen-jun 《Chinese Quarterly Journal of Mathematics》 2024年第4期379-387,共9页
Research on the independence polynomial of graphs has been very active.However,the computational complexity of determining independence polynomials for general graphs remains NP-hard.Letα(G)be the independence number... Research on the independence polynomial of graphs has been very active.However,the computational complexity of determining independence polynomials for general graphs remains NP-hard.Letα(G)be the independence number of G and i(G;k)be the number of independent sets of order k in G,then the independence polynomial is defined as I(G;x)=∑_(k=0)^(α(G))i(G;k)x^(k),i(G;0)=1.In this paper,by utilizing the transfer matrix,we obtain an analytical expression for I(CGn;x)of mono-cylindrical grid graphs CGn and present a crucial proof of it.Moreover,we also explore the Merrifield-Simmons index and other properties of CGn. 展开更多
关键词 independence polynomial Cylindrical grid graphs Transfer matrix Merrifield-Simmons index
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The Path to Growth and Maturity for Young Students: Embracing Independence and Self- Reliance
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作者 Ruimin Chang Qin Zhao 《Journal of Contemporary Educational Research》 2024年第8期290-295,共6页
Young students are the future of our country and the hope of our nation.The healthy growth of young students must rely on independence and self-reliance.From the perspectives of family,society,and school,this article ... Young students are the future of our country and the hope of our nation.The healthy growth of young students must rely on independence and self-reliance.From the perspectives of family,society,and school,this article explores the cultivation of young students’spirit of independence and self-reliance,which should be grasped from three aspects:recognizing the situation,identifying the reasons,and taking effective measures. 展开更多
关键词 Young students SELF-RELIANCE independence PATH
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构建股骨转子间骨折股骨近端防旋髓内钉内固定失效的风险预测模型
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作者 涂泽松 徐大星 +4 位作者 罗洪斌 王宇胜 冯兴伦 彭仲华 杜绍龙 《中国组织工程研究》 CAS 北大核心 2025年第27期5845-5853,共9页
背景:股骨转子间骨折是主要的老年脆性骨折类型,股骨近端防旋髓内钉是首选手术方案,但术后内固定失效的相关因素尚存在争议。目的:通过术前评估患者影像学资料提出一种新的股骨转子间骨折“三柱”分类法,并分析其与术后内固定失效的交... 背景:股骨转子间骨折是主要的老年脆性骨折类型,股骨近端防旋髓内钉是首选手术方案,但术后内固定失效的相关因素尚存在争议。目的:通过术前评估患者影像学资料提出一种新的股骨转子间骨折“三柱”分类法,并分析其与术后内固定失效的交互关系,利用数字技术运算开发和验证风险预测模型,便于临床医生术前甄别并干预高风险患者。方法:选择2012年6月和2022年6月佛山市中医院三水医院收治的股骨转子间骨折患者,按照术后是否出现内固定失效结局,分为内固定失效组和内固定维持组。根据患者术前X射线片将股骨近端分为“三柱”:内侧柱、外侧柱及中柱,每柱均有不同的亚组分型。分析“三柱”的形态特征与股骨近端防旋髓内钉内固定术后复位失效的关系,通过先单因素后多因素logistics回归分析,筛选出引起内固定失效的独立风险因素,根据独立风险因素利用R语言软件构建风险预测模型。采用自助法重抽样1000次,使用受试者工作特征曲线下的面积、校准曲线、临床决策曲线评价模型的区分度、校准能力及临床应用价值。通过Youden指数确定预测模型的最佳风险分界值,据此将患者分为高、低风险组,根据模型风险预测能力的准确度来评价其稳定性和外延性。结果与结论:①利用“三柱”分型系统预测骨折术后内固定失效的4个独立风险因素,分别为内侧柱(小转子及股骨距粉碎性骨折)[优势比=5.385,95%CI(1.961,14.782),P=0.001]、中间柱(烟囱型)[优势比=2.893,95%CI(1.167,7.173),P=0.022]、外侧柱(外侧壁厚度<20.5 mm)[优势比=2.804,95%CI(1.078,7.297),P=0.035]及外侧柱(外侧壁骨折)[优势比=4.278,95%CI(1.670,10.959),P=0.012];②构建的风险预测模型表现出良好的区分度和准确度[受试者工作特征曲线下面积=0.852,95%CI(0.837,0.922)],校准曲线显示模型预测风险和实际发生风险有较好的一致性;③临床决策曲线提示风险阈值概率在0.2-0.82范围内时,模型具有较好的临床适用性;风险概率为28%是模型风险分层的最佳阈值,模型在不同风险组别患者的预测性能较好;④此次研究通过“三柱”分型系统构建预测模型计算股骨转子间骨折患者术后内固定失效的风险概率,此方法准确、简便,易于临床应用,可作为一种数字化工具指导临床个性化治疗。 展开更多
关键词 股骨转子间骨折 股骨近端防旋髓内钉 独立风险因素 内固定失效 分型系统 风险预测模型 骨科植入物
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Resting-state brain network remodeling after different nerve reconstruction surgeries:a functional magnetic resonance imaging study in brachial plexus injury rats
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作者 Yunting Xiang Xiangxin Xing +6 位作者 Xuyun Hua Yuwen Zhang Xin Xue Jiajia Wu Mouxiong Zheng He Wang Jianguang Xu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1495-1504,共10页
Distinct brain remodeling has been found after different nerve reconstruction strategies,including motor representation of the affected limb.However,differences among reconstruction strategies at the brain network lev... Distinct brain remodeling has been found after different nerve reconstruction strategies,including motor representation of the affected limb.However,differences among reconstruction strategies at the brain network level have not been elucidated.This study aimed to explore intranetwork changes related to altered peripheral neural pathways after different nerve reconstruction surgeries,including nerve repair,endto-end nerve transfer,and end-to-side nerve transfer.Sprague–Dawley rats underwent complete left brachial plexus transection and were divided into four equal groups of eight:no nerve repair,grafted nerve repair,phrenic nerve end-to-end transfer,and end-to-side transfer with a graft sutured to the anterior upper trunk.Resting-state brain functional magnetic resonance imaging was obtained 7 months after surgery.The independent component analysis algorithm was utilized to identify group-level network components of interest and extract resting-state functional connectivity values of each voxel within the component.Alterations in intra-network resting-state functional connectivity were compared among the groups.Target muscle reinnervation was assessed by behavioral observation(elbow flexion)and electromyography.The results showed that alterations in the sensorimotor and interoception networks were mostly related to changes in the peripheral neural pathway.Nerve repair was related to enhanced connectivity within the sensorimotor network,while end-to-side nerve transfer might be more beneficial for restoring control over the affected limb by the original motor representation.The thalamic-cortical pathway was enhanced within the interoception network after nerve repair and end-to-end nerve transfer.Brain areas related to cognition and emotion were enhanced after end-to-side nerve transfer.Our study revealed important brain networks related to different nerve reconstructions.These networks may be potential targets for enhancing motor recovery. 展开更多
关键词 brain functional networks end-to-end nerve transfer end-to-side nerve transfer independent component analysis nerve repair peripheral plexus injury resting-state functional connectivity
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Quasi-χ~2 Distribution and the Independence of Wishart Distribution
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作者 朱道元 赵胜利 《Journal of Southeast University(English Edition)》 EI CAS 2002年第2期173-176,共4页
In this paper, the authors generalize the definition of χ 2 distribution and introduce a quasi χ 2 distribution, and then prove several properties of it, find the necessary and sufficient conditions of i... In this paper, the authors generalize the definition of χ 2 distribution and introduce a quasi χ 2 distribution, and then prove several properties of it, find the necessary and sufficient conditions of independence about multivariate normal distributions, matrix normal distributions and two parts of the Wishart distribution. 展开更多
关键词 quasi χ 2 Wishart distribution independence
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Independence Test of Wheat Head Blight Infection
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作者 夏海峰 《Plant Diseases and Pests》 CAS 2010年第5期38-39,53,共3页
The relationship between wheat varieties and occurrence of head blight was discussed, the independence test was carried out by using contingency table.
关键词 Hypothesis testing SAMPLE INDEPENDENT
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The Use of Field Dependence/Independence in Language Acquisition
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作者 操龙升 《海外英语》 2012年第20期114-115,共2页
Field dependence/independence in Language Acquisition are discussed by many language learners.In this article,we will mainly focus on talking about the cognitive style,including the concept of Field-dependence/indepen... Field dependence/independence in Language Acquisition are discussed by many language learners.In this article,we will mainly focus on talking about the cognitive style,including the concept of Field-dependence/independence,their character istics and differences and functions in language acquisition. 展开更多
关键词 FIELD dependence/independence LANGUAGE ACQUISITION
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NONNULL DISTRIBUTION OF THE LIKELIHOOD RATIO CRITERION FOR TESTING THE EQUALITY OF DIAGONAL BLOCKS WITH BLOCKWISE INDEPENDENCE 被引量:5
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作者 A. K. Gupta C. C. Chao(Bowling Green State University Bowling Green, OH 43403-0221 C. C. ChaoJacksonville State Univesity Jacksonville, AL 36265) 《Acta Mathematica Scientia》 SCIE CSCD 1994年第2期195-203,共9页
In this paper, the nonnull moments and the distributions of the likelihood ratio criterion for testing the equality of diagonal blocks with blockwise independence under certain alternatives have derived.
关键词 RATIO BLOCKWISE CRITERION DIAGONAL DISTRIBUTION EQUALITY FOR independence LIKELIHOOD NONNULL
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On the connotation, challenge and significance of China’s “energy independence” strategy 被引量:7
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作者 ZOU Caineng PAN Songqi ZHAO Qun 《Petroleum Exploration and Development》 2020年第2期449-462,共14页
The world’s energy is in the "third major transformation period" from fossil energy to new energy, and all countries in the world have formulated energy development strategies. Through advanced deployment, ... The world’s energy is in the "third major transformation period" from fossil energy to new energy, and all countries in the world have formulated energy development strategies. Through advanced deployment, the United States is about to achieve "energy independence" relying on "unconventional oil and gas revolution". China’s energy development is faced with four challenges:(1) The population base and economic development scale determine the "totally huge amount" of energy consumption;(2) the "coal rich but oil and gas insufficient" resource structure determines the "unclean" energy consuming structure;(3) the increasing dependence on imported oil and gas determines the "unsafe" energy supply;and(4) the unconventional oil and gas endowment makes it impossible to achieve energy independence by copying the American model. From the perspective of the world energy trend and the unique situation of China’s energy, we put forward a "three-step" strategy for China to achieve "energy independence": From 2020 to 2035, "energy supply security" will be addressed by "cleaning coal, stabilizing oil and gas production and vigorously developing new alternative energy";from 2035 to 2050, the vision of "production independence" will be realized by relying on "domestic production and overseas oil and gas mining rights";from 2050 to 2100, "intelligent energy and new energy" will help China realize "energy independence". The two important signs of China’s "energy independence" are that domestic production accounts for more than 90% of the domestic consumption and clean energy production accounts for more than 70%, and energy security realizes "independence and self-control" and "long-term security". The strategic significance of "energy independence" is to ensure national energy security, drive the development of relevant major industries, achieve energy management reform, and implement the environmental protection goal of zero carbon emissions. The "energy independence" of China is a strategic mission, it might be fulfilled in the future with the growth of the state’s power, even when the domestic energy production does not catch up with the domestic consumption. Perhaps the world’s new technological revolution will exceed expectations, and China’s "energy independence" dream will eventually come true. 展开更多
关键词 energy independence energy revolution intelligent energy COAL unconventional oil and gas new energy energy long march
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Sub-independence-spaces 被引量:2
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作者 MAO Huat WANG Gang 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第2期293-299,共7页
Cleverly using the relation of independence spaces and B-matroids, this paper firstly deals with the properties of the closure operator of an independence space, followed by presenting the definitions and solving some... Cleverly using the relation of independence spaces and B-matroids, this paper firstly deals with the properties of the closure operator of an independence space, followed by presenting the definitions and solving some relative properties for the sub-independence spaces of an independence space with the help of circuits. 展开更多
关键词 CIRCUIT sub-independence-space independence space closure operator
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CONSISTENCY BETWEEN INDEPENDENCE THEOREMS AND GENERALIZED SELF-CONSISTENT METHOD 被引量:1
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作者 杜丹旭 郑泉水 高蕴昕 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1997年第4期355-365,共11页
Recently Zheng & Hwang established a series of independence theorems concerning with planar effective elastic properties. It is manifested that the estimation of the effective elastic properties of microcracked so... Recently Zheng & Hwang established a series of independence theorems concerning with planar effective elastic properties. It is manifested that the estimation of the effective elastic properties of microcracked solids through the generalized self-consistent method (GSCM) contradicts with these independence theorems. In this paper it is shown that such contradiction is actually caused by the approximate algorithm adopted, while the exact solution of GSCM is consistent with these rigorously established independence theorems. Since only an approximate algorithm in GCSM is available in dealing with problems involving non-circular inclusions or holes, an intrinsic GSCM is proposed, which can be performed based on an approximate algorithm and the corresponding estimations are consistent with the independence theorems. 展开更多
关键词 intrinsic Generalised Self-Consistent Method independence energy equivalence effective properties
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A View on Independence of Grammar——Extracts from Syntactic Structures
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作者 马昱 《英语广场(学术研究)》 2012年第6期37-38,共2页
According to Chomsky,the grammar of Language is a device that generates all of the grammatical sequences of Language and none of the ungrammatical ones.However,as the foundation of Universal Grammar,independence of gr... According to Chomsky,the grammar of Language is a device that generates all of the grammatical sequences of Language and none of the ungrammatical ones.However,as the foundation of Universal Grammar,independence of grammar is strongly criticized by many other linguists.This paper aims at reviewing the literature and illustrating different ideas towards Universal Grammar. 展开更多
关键词 Universal Grammar independence of grammar CHOMSKY
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Upholding Peace, Development, Independence and Inclusiveness and Renewing the Firm Commitment to Open Regionalism 被引量:1
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作者 Wang Yi 《China International Studies》 2022年第4期5-14,共10页
Over the past 10 years, China-ASEAN relations have entered the fast lane and made accelerating progress, as countries in the region adhere to open regionalism, respect and appreciate the diversities among members, and... Over the past 10 years, China-ASEAN relations have entered the fast lane and made accelerating progress, as countries in the region adhere to open regionalism, respect and appreciate the diversities among members, and uphold and practice the principle of voluntarism. China is ready to join hands with ASEAN members and other regional countries to adhere to the vision of peace, development, independence and inclusiveness, firmly uphold open regionalism, and constantly add new dimensions to open regionalism. 展开更多
关键词 independence PEACE dimensions
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The Criterion of weighting the independence of non-executive directors
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作者 师怡 《商情》 2008年第7期47-,54,共2页
Non-executive directors are now very well established in Chinese business. The uniform and final criterion of weighting the independence of non-executive directors is not available. It will be valuable to draw an anal... Non-executive directors are now very well established in Chinese business. The uniform and final criterion of weighting the independence of non-executive directors is not available. It will be valuable to draw an analogy with the criterion of weighting the independence of non-executive directors in the UK, where over a dozen different criterions are applied. 展开更多
关键词 non-executive directors the independence of non-executive directors CRITERION of weighting the independence
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An Analysis of Judy’s Personality of Independence in Daddy-Long-Legs
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作者 郭雅君 《神州》 2016年第11期3-4,共2页
Daddy- Long- Legs written by Jane Webster in 1912 has been always well received since it was published. In the novel, Miss Webster portrays a female image Judy who remained positive although she grew up in asylum and ... Daddy- Long- Legs written by Jane Webster in 1912 has been always well received since it was published. In the novel, Miss Webster portrays a female image Judy who remained positive although she grew up in asylum and bore the brunt of distressing time. She tried her best to improve her ideas and personality and become a writer and paid back to Daddy- Long-Legs.As a result, she got real love from Daddy- Long-Legs and she also became a typical representative of independent females. The author of the paper aims making more teenagers take Judy as an example and learn from her. What’s more, we can gradually develop our own independent spirit. 展开更多
关键词 Judy independence growth CHARACTER ANALYSIS
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机器学习模型在亚急性期脑卒中患者康复后功能结局预测中的价值研究
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作者 曾形信 赖奕杉 殷敏 《中医康复》 2025年第1期12-17,共6页
目的:探讨机器学习模型与逐步线性回归(Stepwise linear regression,SLR)模型在亚急性期脑卒中患者康复后功能结局预测中的价值。方法:选取中国人民解放军联勤保障部队第九四五医院2013年1月~2023年12月收治的亚急性期脑卒中患者1046例... 目的:探讨机器学习模型与逐步线性回归(Stepwise linear regression,SLR)模型在亚急性期脑卒中患者康复后功能结局预测中的价值。方法:选取中国人民解放军联勤保障部队第九四五医院2013年1月~2023年12月收治的亚急性期脑卒中患者1046例为研究对象,取患者一般资料以及入院时功能独立性量表(Functional Independence Measure,FIM)评分构建SLR、回归树(Regression trees.RT)、集成学习(Ensemble learning,EL)、人工神经网络(Artificial neural network,ANN)、支持向量回归(Support vector regression,SVR)以及高斯过程回归(Gaussian process regression,GPR)预测模型,并采用10折交叉验证,比较各模型实际与预测出院FIM评分以及FIM增益的决定系数(R^(2))、均方根误差(Root Mean Squared Error,RMSE)。结果:机器学习模型(R^(2):RT=0.75,EL=0.78,ANN=0.81,SVR=0.80,GPR=0.81)在预测FIM运动评分方面优于SLR(0.70)。机器学习模型对FIM增益总分的预测准确性(R^(2):RT=0.48,EL=0.51,ANN=0.50,SVR=0.51,GPR=0.54)也优于SLR(0.22)。结论:机器学习模型在预测FIM预后方面优于SLR:仅包含患者一般信息和入院FIM评分的机器学习模型的预测准确性优于既往研究,同时GPR对FIM预后的预测准确性最高。 展开更多
关键词 脑卒中 亚急性期 机器学习 预测 功能独立性量表 逐步线性回归 人工神经网络
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LINEAR INDEPENDENCE OF THE INTEGER TRANS-LATES OF COMPACTLY SUPPORTED DISTRIBU-TIONS AND REFINABLE VECTORS
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作者 Sun QiyuDept. of Math.,National University of Singapore,10 Kent Ridge Crescent,Singapore 119260,Singapore. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第4期381-396,共16页
In this paper,the global and local linear independence of any compactly supported distributions by using time domain spaces,and of refinable vectors by invariant linear spaces are investigated.
关键词 Global linear independence local linear independence refinable vector invariant space.
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The Researches on Path Independence Problem
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作者 Luo Yunfeng Xiao Renbin & Zhu Mingfu(Institute of Systems Engineering, Huazhong University of Science and Technology,Wuhan 430074, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第2期19-22,共4页
Rationality condition is imposed in Arrow's General Possibility Theorem in order for social choice to be independent of the path of choice. In this Paper, emphasis is laid on the analysis of the relevance of path ... Rationality condition is imposed in Arrow's General Possibility Theorem in order for social choice to be independent of the path of choice. In this Paper, emphasis is laid on the analysis of the relevance of path independence and rationality condition. Two kinds of Path independence, i.e., Plott's path independence and Bandyopadhyay's sequential path independence, are shown, and their meanings with respect to the problem are investigated. 展开更多
关键词 Social choice Rationality condition Path independence Sequential path independence
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Testing conditional independence with data missing at random
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作者 LIU Yi LIU Xiao-hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2018年第3期298-312,共15页
It is known that conditional independence is a quite basic assumption in many fields of statistics. How to test its validity is of great importance and has been extensively studied by the literature. Nevertheless, all... It is known that conditional independence is a quite basic assumption in many fields of statistics. How to test its validity is of great importance and has been extensively studied by the literature. Nevertheless, all of the existing methods focus on the case that data are fully observed, but none of them seems having taken into account of the scenario when missing data are present. Motivated by this, this paper develops two testing statistics to handle such a situation relying on the idea of inverse probability weighted and augmented inverse probability weighted techniques. The asymptotic distributions of the proposed statistics are also derived under the null hypothesis. The simulation studies indicate that both testing statistics perform well in terms of size and power. 展开更多
关键词 conditional independence cumulative sum process of residuals missing at random inverse probability weighting re-sampling
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