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80 个结果
  • 简介:Considersolvinganoverdeterminedsystemoflinearalgebraicequationsbyboththeleastsquaresmethod(LS)andthetotalleastsquaresmethod(TLS).Extensivepublishedcomputationalevidenceshowsthatwhentheoriginalsystemisconsistent.oneoftenobtainsmoreaccuratesolutionsbyusingtheTLSmethodratherthantheLSmethod.ThesenumericalobservationscontrastwithexistinganalyticperturbationtheoriesfortheLSandTLSmethodswhichshowthattheupperboundsfortheLSsolutionarealwayssmallerthanthecorrespondingupperboundsfortheTLSsolutions.InthispaperwederiveanewupperboundfortheTLSsolutionandindicatewhentheTLSmethodcanbemoreaccuratethantheLSmethod.Manyappliedproblemsinsignalprocessingleadtooverdeterminedsystemsoflinearequationswherethematrixandrighthandsidearedeterminedbytheexperimentalobservations(usuallyintheformofalimeseries).Itoftenhappensthatasthenumberofcolumnsofthematrixbecomeslarger,thera

  • 标签: Least SQUARES TOTAL least SQUARES ACCURACY
  • 简介:LetGbeasimplegraphwithnverticesandλn(G)betheleasteigenvalueofG.Inthispaper,weshowthat,ifGisconnectedbutnotcomplete,thenλn(G)≤λn(Kn-11)andtheequalityholdsifandonlyifGKn-11,whereKn-11,isthegraphobtainedbythecoalescenceofacompletegraphKn-1ofn-1verticeswithapathP2oflengthoneofitsvertices.

  • 标签: ADJACENCY MATRIX EIGENVALUE COALESCENCE
  • 简介:Datafittingisanextensivelyemployedmodelingtoolingeometricdesign.Withtheadventofthebigdataera,thedatasetstobefittedaremadelargerandlarger,leadingtomoreandmoreleast-squaresfittingsystemswithsingularcoefficientmatrices.LSPIA(least-squaresprogressiveiterativeapproximation)isanefficientiterativemethodfortheleast-squaresfitting.However,theconvergenceofLSPIAforthesingularleast-squaresfittingsystemsremainsasanopenproblem.Inthispaper,theauthorsshowedthatLSPIAforthesingularleast-squaresfittingsystemsisconvergent.Moreover,inaspecialcase,LSPIAconvergestotheMoore-Penrose(M-P)pseudo-inversesolutiontotheleast-squaresfittingresultofthedataset.ThispropertymakesLSPIA,aniterativemethodwithcleargeometricmeanings,robustingeometricmodelingapplications.Inaddition,theauthorsdiscussedsomeimplementationdetailofLSPIA,andpresentedanexampletovalidatetheconvergenceofLSPIAforthesingularleast-squaresfittingsystems.

  • 标签: Data FITTING GEOMETRIC modeling LSPIA SINGULAR
  • 简介:1.IntroductionThepurposeofthispaperistostudytheleastsquaresproblemofthematrixequationF~PGwithrespecttoPcSa,i.e.(PI)R\qIIF--PGll,whereF,GERnxmandG/0.Where11’11denotestheFrobeniusnorm,andSa~{XeS'fX20},S'={XER'''IX=X'}.Problem(PI)wasfirstformulatedbyAll...

  • 标签: Least SQUARES solution MATRIX equation INVERSE
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  • 简介:AnegativecurvaturemethodisappliedtononlinearleastsquaresproblemswithindefiniteHessianapproximationmatrices.Withthespecialstructureofthemethod,anewswitchisproposedtoformahybridmethod.Numericalexperimentsshowthatthismethodisfeasibleandeffectiveforzero-residual,small-residualandlarge-residualproblems.

  • 标签: 杂交法 最小二乘问题 非线性 曲率 数值逼近
  • 简介:Thispaperdiscussespointwiseerrorestimatesfortheapproximationbyboundedlinearoperatorsofcontinuousfunctionsdefinedoncompactmetricspaces(X,d),Theauthorsintroduceanewmajorautofthemodulusofthecontinuitywhichisthesrnallestamongthoseg(ξ)'swhichhavethefollowingpropertiesω(f,ε)≤9(f,ε)andg(f,λε)≤(1+λ)g(f,ε)andbythismajorantanewquantitativeKorovkintypetheoremonanycompactmetricspaceisproved.

  • 标签: 最小支配连续模 数值近似 紧空间 有界线性算子
  • 简介:一张签署的图是一张图,一个符号属于每个边。这篇论文从图扩大拉普拉斯算符矩阵的一些基本概念到签署的图。Inparticular,在最少的拉普拉斯算符特征值之间的关系和一张签署的图的失衡的海角被调查。

  • 标签: LAPLACIAN算子 特征值 符号图 LAPLACIAN矩阵
  • 简介:Inthispaper,wepresentsomeiterativemethodsforsolvinglthorderautoregressivemodels,proveglobalconvergenceforl=1case,andthenumericalresultsofnewalgorithmsseemtobemoreefficientthantheonesofCochrane-Orcuttiterativemethod.

  • 标签: AUTOREGRESSIVE MODEL ITERATIVE METHOD convergence.
  • 简介:TheGalerkinandleast-squaresmethodsaretwoclassesofthemostpopularKrylovsubspacemethOdsforsolvinglargelinearsystemsofequations.Unfortunately,boththemethodsmaysufferfromseriousbreakdownsofthesametype:InabreakdownsituationtheGalerkinmethodisunabletocalculateanapproximatesolution,whiletheleast-squaresmethod,althoughdoesnotreallybreakdown,isunsucessfulinreducingthenormofitsresidual.Inthispaperwefrstestablishaunifiedtheoremwhichgivesarelationshipbetweenbreakdownsinthetwometh-ods.Wefurtherillustratetheoreticallyandexperimentallythatifthecoefficientmatrixofalienarsystemisofhighdefectivenesswiththeassociatedeigenvalueslessthan1,thentherestart-edGalerkinandleast-squaresmethodswillbeingreatrisksofcompletebreakdowns.Itappearsthatourfindingsmayhelptounderstandphenomenaobservedpracticallyandtoderivetreat-mentsforbreakdownsofthistype.

  • 标签: large linear systems iterative methods Krylov
  • 简介:Weproveconvergenceforameshfreefirst-ordersystemleastsquares(FOSLS)partitionofunityfiniteelementmethod(PUFEM).Essentially,byvirtueofthepartitionofunity,localapproximationgivesrisetoglobalapproximationinH(div)∩H(curl).TheFOSLSformulationyieldslocalaposteriorierrorestimatestoguidethejudiciousallotmentofnewdegreesoffreedomtoenrichtheinitialpointsetinameshfreedis-cretization.Preliminarynumericalresultsareprovidedandremainingchallengesarediscussed.

  • 标签: 适应有限元 最小方程式 数学模型 计算数学
  • 简介:Physicalactivity(PA)isaneffectivemeansofcurbingtheprevalenceofchildobesity,andfundamentalskillsarehypothesizedtobeanimportantfactorthatdeterminesphysicallyactiveorinactivebehaviorinchildren.Researchevidencesuggeststhatadolescentsandyoungadultswithproficientmotorskillsinsport-relatedactivitiesaremorelikelytohaveaphysicallyactivelifestyle.1Becausephysically

  • 标签: 学龄前儿童 运动 体力 预测能力 生活方式 成年人
  • 简介:最少的广场LS时间延期评价是一个古典、有效的方法。然而,表演由于矩阵inversing的不稳定性在信号噪音SNR的低比率的情形严重地被降级。以便解决这个问题,装载最少的广场DL-LS的对角线被把一个积极明确的矩阵加到反的矩阵建议。而且,修理斜装载的缺点从规则化的点被分析当低SNR的忍耐被增加时,诚实被减少。这个问题被再装解决。主要评价相互作为斜装载被介绍,它导致在到达并且在另外的时间的更大的装载的时候的小斜装载。模拟和水池实验证明算法有更好的性能。

  • 标签: 对角加载 最小二乘 时延估计 时间延迟估计 低信噪比 矩阵反演
  • 简介:SeveralARMAmodelingapproachesareaddressed.Inthesemethodsonlypartofacorrelationsequenceisemployedforestimatingparameters.Itissatisfying,ifthegivencorrelationsequenceisofrealARMA,sinceanARMAprocesscanbecompletelydeterminedbypartofitscorrelationse-quence.Butforthecaseofameasuredcorrelationsequencethewholesequencemaybeusedtore-ducetheeffectoferroronmodelparameterestimation.Inaddition,thesemethodsnowdonotguar-anteeanonnegativespectralestimate.Inviewoftheabove-mentionedfact,aconstrainedleastsquaresfittingtechniqueisproposedwhichutilizesthewholemeasuredcorrelationsequenceandguar-anteesanonnegativespectralestimate.

  • 标签: fitting ESTIMATING addressed CONSTRAINED NONNEGATIVE satisfying
  • 简介:半的答案性质参量的模型被分析,特别,最不惩罚了那为半摆平参量的模型当矩阵B~TPB是ill-posedor时,将无效单个。根据为线性参量的模型的山脉估计的原则,为半概括了惩罚最少的广场参量的模型被提出,并且一些公式和估计的统计性质被导出。最后,根据模拟例子,一些有用结论被得出。

  • 标签: 参量模型 大地测量 测量平差 岭估计
  • 简介:增加的算法是过去常改进回归分析的一般性能的一般方法的一个类。主要想法是在火车集合上维持分布。以便直接使用给定的分发,一请修改了算法被建议并且用作基础学习者处理非线性多变量回归问题。Experimentson汽油辛烷数字预言表明那增加请修改了算法在PLS算法上有更好一般的性能。

  • 标签: 增压算法 局部最小平方 PLS 回归模型 多变量回归
  • 简介:LetMbeacompactorientable3-manifoldwithMconnected.IfV∪SWisaHeegaardsplittingofMwithdistanceatleast6,thenthe-stabilizationofV∪SWalongMisunstabilized.HenceMhasatleasttwounstabilizedHeegaardsplittingswithdifferentgenera.ThebasictoolisaresultondiskcomplexgivenbyMasurandSchleimer.

  • 标签: 不稳定 距离 劈裂 Heegaard分裂 镇定 络合物
  • 简介:LetG=(V(G),E(G))beasimpleconnectedgraphofordern.Foranyverticesu,v,w∈V(G)withuv∈E(G)anduw∈E(G),anedge-rotatingofGmeansrotatingtheedgeuv(aroundu)tothenon-edgepositionuw.Inthiswork,weconsiderhowtheleasteigenvalueofagraphperturbswhenthegraphisperformedbyrotatinganedgefromtheshorterhangingpathtothelongerone.

  • 标签: 最小特征值 旋转定理 简单连通图 紫外线 顶点
  • 简介:Byusingthenon-parametricleastsquaremethod,thestrongconsistentestimationsofdistributionfunctionandfailurefunctionareestablished,wherethedistributionfunctionF(x)afterlogisttransformationisassumedtobeapproximatedbyapolynomial.Theperformanceofsimulationshowsthattheestimationsarehighlysatisfactory.

  • 标签: 分布函数 最小二乘 估计 非参数