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基于确定性退火的增强型分片回归 被引量:1
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作者 张讲社 杨雨茜 +1 位作者 陈晓文 周成虎 《中国科学(E辑)》 CSCD 北大核心 2008年第8期1244-1254,共11页
回归是统计学习理论中的主要研究问题之一.文中给出确定性退火分片回归算法全局收敛性和自由能全局极小关于温度连续性的证明,推导出初始临界温度的简化计算公式,并提出一种新的增强型分片回归算法,利用"原型迁移"技巧,避免... 回归是统计学习理论中的主要研究问题之一.文中给出确定性退火分片回归算法全局收敛性和自由能全局极小关于温度连续性的证明,推导出初始临界温度的简化计算公式,并提出一种新的增强型分片回归算法,利用"原型迁移"技巧,避免退火过程中"空剖分"的出现.基于Benchmark数据集上的实验表明:新算法能有效去除模型冗余,提高学习泛化能力. 展开更多
关键词 统计回归 分片回归 确定性退火 泛化能力
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基于分片逆回归的小样本组合预测建模方法 被引量:6
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作者 谢力 魏汝祥 +1 位作者 蒋国萍 林名池 《统计与决策》 CSSCI 北大核心 2013年第2期73-76,共4页
针对在基于回归的小样本组合预测中,容易出现预测模型多于用于组合预测的样本数量,导致回归系数无法估计的问题,文章从信息重组的角度对组合预测建模方法进行了研究。首先采用三次样本插值对原始样本容量进行扩充,然后采用采用分片逆回... 针对在基于回归的小样本组合预测中,容易出现预测模型多于用于组合预测的样本数量,导致回归系数无法估计的问题,文章从信息重组的角度对组合预测建模方法进行了研究。首先采用三次样本插值对原始样本容量进行扩充,然后采用采用分片逆回归方法对扩充后的样本进行降维处理,并在此基础上构建基于回归的小样本组合预测模型。最后实例通过与常用组合预测方法结果的比较说明了该方法的可行性和有效性。 展开更多
关键词 组合预测 小样本 分片回归 三次样条插值 降维
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基于分片逆回归方法的线性与非线性判别分析的应用比较 被引量:1
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作者 胡煜 《广东技术师范学院学报》 2010年第9期10-13,共4页
所统计分析的数据集是前列腺癌基因数据集.采用分片逆回归方法和线性判别分析(LDA),二次判别分析(QDA).对基因芯片(微阵列)数据进行分析.用SIR降维,用LDA和QDA分类.讨论分片逆回归方法和二种方法对基因样本进行分类的效果.
关键词 线性判别分析(LDA) 二次判别分析(QDA) 分片回归方法
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分片逆回归中不同方法的比较研究 被引量:2
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作者 陈道铨 田茂再 《统计与决策》 CSSCI 北大核心 2010年第4期8-10,共3页
在多元统计分析中,分片逆回归在处理降维问题时十分有效。假设因变量Y和p维解释变量X满足Y=f(β1TX,…,βkTX,ε),则可以通过分片逆回归估计由βi生成的子空间,从而达到降维的目的。其中涉及到对E[Cov(X|Y)]或Cov[E(X|Y)]的估计,对此Li(... 在多元统计分析中,分片逆回归在处理降维问题时十分有效。假设因变量Y和p维解释变量X满足Y=f(β1TX,…,βkTX,ε),则可以通过分片逆回归估计由βi生成的子空间,从而达到降维的目的。其中涉及到对E[Cov(X|Y)]或Cov[E(X|Y)]的估计,对此Li(1991)、Zhu和Ng(1995)以及Tian和Li(2004)等人曾提出几种不同的估计方法。文章通过蒙特卡洛模拟对它们进行比较研究,发现Zhu和Ng的方法对函数形式不敏感,因而适用性较广;同时对Tian和Li(2004)的方法作了适当推广。 展开更多
关键词 分片回归 拟残差 高阶降维
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基于分片逆回归方法的两种有监督分类方法的应用比较
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作者 胡煜 《福建电脑》 2008年第7期31-32,40,共3页
本文所统计分析的数据集是前列腺癌基因数据集。采用分片逆回归方法和二种有监督分类的方法:k-近邻法(KNN),支持向量机(SVM)。对基因芯片(微阵列)数据进行分析。用SIR降维,用KNN和SVM分类。讨论分片逆回归方法和二种方法对基因样本进行... 本文所统计分析的数据集是前列腺癌基因数据集。采用分片逆回归方法和二种有监督分类的方法:k-近邻法(KNN),支持向量机(SVM)。对基因芯片(微阵列)数据进行分析。用SIR降维,用KNN和SVM分类。讨论分片逆回归方法和二种方法对基因样本进行分类的效果。 展开更多
关键词 基因芯片数据分析 K-近邻法 支持向量机 分片回归方法
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高维参数poisson回归模型的估计方法
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作者 张艳杰 李树有 宓颖 《辽宁工业大学学报(自然科学版)》 2013年第3期200-204,共5页
对高维参数poisson回归模型进行了参数估计,高维参数poisson回归模型用极大似然法直接估计参数向量比较困难。基于逆回归,给出了一种新的估计方法,第一步用分片逆回归方法,计算参数单位向量的估计,将高维参数降维;第二步用极大似然法,... 对高维参数poisson回归模型进行了参数估计,高维参数poisson回归模型用极大似然法直接估计参数向量比较困难。基于逆回归,给出了一种新的估计方法,第一步用分片逆回归方法,计算参数单位向量的估计,将高维参数降维;第二步用极大似然法,估计参数向量的模,最后得到参数的相合估计,并运用该方法进行了实例分析。 展开更多
关键词 分片回归 poisson回归模型 极大似然估计
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Regression Relationship between WI and FMC at Different Growth Periods of Sawtooth Oaks Leaf 被引量:2
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作者 费鲜芸 张志国 +2 位作者 卢霞 高祥伟 何润昭 《Agricultural Science & Technology》 CAS 2010年第7期49-52,共4页
[Objective] The aim was to study the regression relationship between water index (WI) and fuel moisture content (FMC) of different growth periods of sawtooth oaks leaf.[Method] Taking sawtooth oaks in Huaguo Mount... [Objective] The aim was to study the regression relationship between water index (WI) and fuel moisture content (FMC) of different growth periods of sawtooth oaks leaf.[Method] Taking sawtooth oaks in Huaguo Mountain,Lianyungang City as research object,the sensitivity of WI to leaf FMC was studied at leaf level,and statistical characteristics were analyzed.[Result] The WI of sawtooth oaks leaves was sensitive to the changes of FMC,and the line regression level between them was significant.A fitting curve between leaf FMC and WI was obtained.[Conclusion] The research provides reference for acquisition methods of vegetation water remote sensing within the range of study area. 展开更多
关键词 High spectral Fuel moisture index Water content Regression analysis Swatooth oaks leaf
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SIR方法在小型二次电池市场分析上的应用 被引量:3
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作者 周文琴 冯鸣鸣 王惠文 《数理统计与管理》 CSSCI 北大核心 2001年第6期5-9,18,共6页
在新型电池的研究与发展过程中 ,日本小型电池市场发展最具代表性。本文采用分片逆回归方法 (SlicedInverseRegression ,简称SIR) ,在非线性模型的假设下 ,利用日本小型二次电池市场的数据 ,对影响小型二次电池市场销售额的主要因素进... 在新型电池的研究与发展过程中 ,日本小型电池市场发展最具代表性。本文采用分片逆回归方法 (SlicedInverseRegression ,简称SIR) ,在非线性模型的假设下 ,利用日本小型二次电池市场的数据 ,对影响小型二次电池市场销售额的主要因素进行综合与提炼 ,以较高的精度将高维自变量集合综合成一维变量 ,并建立了镍镉电池、镍氢电池和锂离子电池市场年销售额的预测模型。由于经SIR降维后 ,三种电池的预测模型均为一元回归模型 。 展开更多
关键词 SIR方法 预测模型 小型二次电池市场 分片回归方法 发展趋势
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基于大数据的安全态势感知系统 被引量:1
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作者 王焱 孟繁镇 +2 位作者 滕之菁 晏明昱 徐欢 《信息与电脑》 2021年第3期217-219,共3页
随着移动互联网的发展,国内基于Web服务端的流量急剧增加,导致互联网存在的安全风险和入侵威胁等问题亟待解决.因此,阐述大数据下安全态势感知系统的设计与实现,通过性能分析确定系统的可行性,并展望了大数据的发展前景和面临的挑战。
关键词 大数据 异常流量检测 安全态势感知 回归分片学习
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UGT1A1 predicts outcome in colorectal cancer treated with irinotecan and fluorouracil 被引量:34
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作者 Yan Wang Lin Shen +4 位作者 Nong Xu Jin-Wan Wang Shun-Chang Jiao Ze-Yuan Liu Jian-Ming Xu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第45期6635-6644,共10页
AIM:To evaluate effects of UDP-glucuronosyltransferase1A1(UGT1A1) and thymidylate synthetase(TS) gene polymorphisms on irinotecan in metastatic colorectal cancer(mCRC).METHODS:Two irinotecan-and fluorouracil-based reg... AIM:To evaluate effects of UDP-glucuronosyltransferase1A1(UGT1A1) and thymidylate synthetase(TS) gene polymorphisms on irinotecan in metastatic colorectal cancer(mCRC).METHODS:Two irinotecan-and fluorouracil-based regimens,FOLFIRI and IFL,were selected as second-line therapy for 138 Chinese mCRC patients.Genomic DNA was extracted from peripheral blood samples before treatment.UGT1A1 and TS gene polymorphisms were determined by direct sequencing and restriction fragment length polymorphism,respectively.Gene polymorphisms of UGT1A1*28,UGT1A1*6 and promoter enhancer region of TS were analyzed.The relationship between genetic polymorphisms and clinical outcome,that is,response,toxicity and survival were assessed.Pharmacokinetic analyses were performed in a subgroup patients based on different UGT1A1 genotypes.Plasma concentration of irinotecan and its active metabolite SN-38 and inactive metabolite SN-38G were determined by high performance liquid chromatography.Differences in irinotecan and its metabolites between UGT1A1 gene variants were compared.RESULTS:One hundred and eight patients received the FOLFIRI regimen,29 the IFL regimen,and one irinotecan monotherapy.One hundred and thirty patients were eligible for toxicity and 111 for efficacy evaluation.One hundred and thirty-six patients were tested for UGT1A1*28 and *6 genotypes and 125 for promoter enhancer region of TS.Patients showed a higher frequency of wild-type UGT1A1*28(TA6/6) compared with a Caucasian population(69.9% vs 45.2%).No significant difference was found between response rates and UGT1A1 genotype,although wild-type showed lower response rates compared with other variants(17.9% vs 24.2% for UGT1A1*28,15.7% vs 26.8% for UGT1A1*6).When TS was considered,the subgroup with homozygous UGT1A1*28(TA7/7) and non-3RG genotypes showed the highest response rate(33.3%),while wild-type UGT1A1*28(TA6/6) with non-3RG only had a 13.6% response rate,but no significant difference was found.Logistic regression showed treatment duration was closely linked to clinical response.In toxicity comparison,UGT1A1*28 TA6/6 was associated with lower incidence of grade 2-4 diarrhea(27.8% vs 100%),and significantly reduced the risk of grade 4 neutropenia compared with TA7/7(7.8% vs 37.5%).Wild-type UGT1A1*6(G/G) tended to have a lower incidence of grade 3/4 diarrhea vs homozygous mutant(A/A) genotype(13.0% vs 40.0%).Taking UGT1A1 and TS genotypes together,lower incidence of grade 2-4 diarrhea was found in patients with non-3RG TS genotypes,when TA6/6 was compared with TA7/7(35.3% vs 100.0%).No significant association with time to progression(TTP) and overall survival(OS) was observed with either UGT1A1 or TS gene polymorphisms,although slightly longer TTP and OS were found with UGT1A1*28(TA6/6).Irinotecan PK was investigated in 34 patients,which showed high area under concentration curve(AUC) of irinotecan and SN-38,but low AUC ratio(SN-38G /SN-38) in those patients with UGT1A1*28 TA7/7.CONCLUSION:A distinct distribution pattern of UGT1A1 genotypes in Chinese patients might contribute to relatively low toxicity associated with irinotecan and 5-fluorouracil in mCRC patients. 展开更多
关键词 IRINOTECAN Fluorouracil UDP-glucurono-syltransferaselA1 Thymidylate synthetase Polymor-phisms PHARMACOKINETICS Treatment outcome Toxic-ity Metastatic colorectal cancer
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Association between gastric cancer and -1993 polymorphism of TBX21 gene 被引量:2
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作者 Le-Hui Zhang Qin Li +5 位作者 Peng Li Sheng-Tao Zhu Jing Wang Hong-Li Yang Chang-Qing Xu Xiu-Hua Guo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第10期1117-1122,共6页
AIM: To investigate the association between the polymorphism of TBX21 gene and the risk of gastric cancer in a Chinese population. METHODS: The -1993 polymorphism located in TBX21 gene promoter region was identified b... AIM: To investigate the association between the polymorphism of TBX21 gene and the risk of gastric cancer in a Chinese population. METHODS: The -1993 polymorphism located in TBX21 gene promoter region was identified by polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP) method. The risk between TBX21 gene genotype and gastric cancer was determined by multivariate logistic regression analysis in 220 gastric cancer patients and 262 cancer-free controls matched by age, sex and ethnicity. RESULTS: Compared with the TBX21 -1993TT genotype, the -1993CC genotype exhibited a significantly elevated risk for gastric cancer [Odds ratio (OR) = 3.42, 95% confidence interval (CI): 1.41-8.31]. The relation-ship between the -1993 polymorphic genotype and the invasive status such as lymph node and distant metastasis was found among the gastric cancer patients (OR = 4.02, 95% CI: 1.87-8.66; OR = 7.02, 95% CI: 3.44-14.34, respectively). CONCLUSION: TBX21 -1993 polymorphism might contribute to the risk of gastric cancer, especially to the distant metastasis. 展开更多
关键词 TBX21 gene Gastric cancer POLYMORPHISM Genetic susceptibility Association analysis
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Theoretical analysis of thermoviscoelastic contact between friction lining and wire rope in mine friction hoists 被引量:2
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作者 PENG Yu-xing ZHU Zhen-cai CHEN Guo-an 《Mining Science and Technology》 EI CAS 2009年第4期518-521,共4页
Serious accidents of mine hoists caused by high-speed sliding between friction lining and wire rope are often seen in coal mines.In order to solve this problem,we analyzed the contact characteristics between friction ... Serious accidents of mine hoists caused by high-speed sliding between friction lining and wire rope are often seen in coal mines.In order to solve this problem,we analyzed the contact characteristics between friction lining and wire rope.Then we carried out a dynamic mechanical analysis(DMA) to explain the change in mechanical properties of the friction lining as function of temperature and load frequency and found that temperature has a stronger effect on the mechanical properties than the frequency.We used multiple regression analysis to obtain the thermoviscoelastic constitutive relations of the friction lining.As well we derived the analytic solution for the thermoviscoelastic contact radius and pressure by combining the theory of viscoelastic contact mechanics with thermoviscoelastic constitutive relations. 展开更多
关键词 contact mechanics THERMOVISCOELASTICITY friction lining dynamic mechanical analysis mine hoist
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考虑多参数空间变异性的非饱和土石坝坝坡可靠度分析 被引量:1
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作者 邓志平 邹艺 +3 位作者 潘敏 郑克红 牛景太 蒋水华 《应用基础与工程科学学报》 EI CSCD 北大核心 2024年第4期1108-1123,共16页
准确地进行非饱和土石坝坝坡可靠度分析需综合考虑土体抗剪强度参数和水力参数的空间变异性.这种多参数问题常因随机场离散的变量过多而造成维度灾难,传统分析方法难以适用.为此,提出了一种基于分片逆回归(SIR)的多元自适应回归样条(MA... 准确地进行非饱和土石坝坝坡可靠度分析需综合考虑土体抗剪强度参数和水力参数的空间变异性.这种多参数问题常因随机场离散的变量过多而造成维度灾难,传统分析方法难以适用.为此,提出了一种基于分片逆回归(SIR)的多元自适应回归样条(MARS)土石坝坝坡可靠度分析方法.该方法采用SIR降维,经降维后的变量矩阵通过MARS构建代理模型,进而采用蒙特卡洛模拟(MCS)评估土石坝坝坡失效概率.以某一土石坝为例,验证了所提方法的有效性,并探讨了计算结果随各参数空间变异性的变化规律,分析了滑坡规模与频率间的关系.研究结果表明:抗剪强度参数变异性对坝坡失效概率的影响大于水力参数变异性的影响;所提方法在各参数变异系数变化的情况下都能得出准确的计算结果,并有效地降低计算成本;该方法可为高维及小失效概率非饱和土石坝坝坡可靠度问题提供一条有效的途径. 展开更多
关键词 土石坝 空间变异性 可靠度分析 非饱和渗流 分片回归 多元自适应回归样条 规模-频率分布
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