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1.
首先给出了互反判断矩阵与一致性互反判断矩阵集之间距离的定义,基于此定义,提出了一个新的互反判断矩阵一致性指标,并给出了此一致性指标的度量方法。对于不满足此一致性指标的互反判断矩阵,提出了一个迭代算法来提高其一致性程度。得出了群体互反判断矩阵一致性指标的下界,为提出的一致性指标应用于群决策问题提供了理论基础。最后用数值例子说明了该迭代算法的可行性和有效性以及群决策中的相关结论。  相似文献   

2.
A new consistency measure, the harmonic consistency index, is obtained for any positive reciprocal matrix in the analytic hierarchy process. We show how this index varies with changes in any matrix element. A tight upper bound is provided for this new consistency measure when the entries of matrix are at most 9, as is often recommended. Using simulation, the harmonic consistency index is shown to give numerical values similar to the standard consistency index but it is easier to compute and interpret. In addition, new properties of the column sums of reciprocal matrices are obtained.  相似文献   

3.
Approaches to consistency adjustment   总被引:5,自引:0,他引:5  
  相似文献   

4.
In order to simulate the uncertainty associated with impression or vagueness, a decision maker may give her/his judgments by means of triangular fuzzy reciprocal preference relations in the process of decision making. The study of their consistency becomes a very important aspect to avoid a misleading solution. Based on the reciprocity property, this paper proposes a new definition of consistent triangular fuzzy reciprocal preference relations. The new definition is different from that reduced by consistent fuzzy reciprocal preference relations proposed by Buckley (1985). The properties of consistent triangular fuzzy reciprocal preference relations in the light of the new definition are studied in detail. In addition, the shortcomings of the proof procedure of the proposition given by Wang and Chen (2008) are pointed out. And the proposition is reproved by using the new definition of consistent triangular fuzzy reciprocal preference relations. Finally, using the (n − 1) restricted comparison ratios, a method for obtaining consistent triangular fuzzy reciprocal preference relations is proposed, and an algorithm is shown to make a consistent decision ranking. Numerical results are further calculated to illustrate the new definition and the obtained algorithm.  相似文献   

5.
Regression function estimation from independent and identically distributed bounded data is considered. TheL 2 error with integration with respect to the design measure is used as an error criterion. It is shown that the kernel regression estimate with an arbitrary random bandwidth is weakly and strongly consistent forall distributions whenever the random bandwidth is chosen from some deterministic interval whose upper and lower bounds satisfy the usual conditions used to prove consistency of the kernel estimate for deterministic bandwidths. Choosing discrete bandwidths by cross-validation allows to weaken the conditions on the bandwidths. Research supported by DAAD, NSERC and Alexander von Humboldt Foundation. The research of the second author was completed during his stay at the Technical University of Szczecin, Poland.  相似文献   

6.
Stuart  A. M. 《Numerical Algorithms》1997,14(1-3):227-260
The numerical solution of initial value problems for ordinary differential equations is frequently performed by means of adaptive algorithms with user-input tolerance τ. The time-step is then chosen according to an estimate, based on small time-step heuristics, designed to try and ensure that an approximation to the local error commited is bounded by τ. A question of natural interest is to determine how the global error behaves with respect to the tolerance τ. This has obvious practical interest and also leads to an interesting problem in mathematical analysis. The primary difficulties arising in the analysis are that: (i) the time-step selection mechanisms used in practice are discontinuous as functions of the specified data; (ii) the small time-step heuristics underlying the control of the local error can break down in some cases. In this paper an analysis is presented which incorporates these two difficulties. For a mathematical model of an error per unit step or error per step adaptive Runge–Kutta algorithm, it may be shown that in a certain probabilistic sense, with respect to a measure on the space of initial data, the small time-step heuristics are valid with probability one, leading to a probabilistic convergence result for the global error as τ→0. The probabilistic approach is only valid in dimension m>1 this observation is consistent with recent analysis concerning the existence of spurious steady solutions of software codes which highlights the difference between the cases m=1 and m>1. The breakdown of the small time-step heuristics can be circumvented by making minor modifications to the algorithm, leading to a deterministic convergence proof for the global error of such algorithms as τ→0. An underlying theory is developed and the deterministic and probabilistic convergence results proved as particular applications of this theory. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

7.
标度系统一致性矩阵容量的计算方法   总被引:4,自引:0,他引:4  
本文研究正互反矩阵的变换性质 ,提出一种保持正互反矩阵一致性程度的等价分类 ,为计算各种标度系统下的一致矩阵容量提供了计算方法  相似文献   

8.
衡量互反矩阵一致性的一种新指标   总被引:1,自引:0,他引:1  
郑明  沈怡 《运筹学学报》2000,4(1):81-85
本文针对AHP中利用几何平均值来估计各因素权向量的方法提出了与之匹配的一种新的衡量互反矩阵一致性的指标,并且制定了相应的衡量标准,同时将其与利用最大特征值所建立的指标入标准进行了比较与讨论。  相似文献   

9.
一种校正模糊判断矩阵一致性的新方法   总被引:22,自引:4,他引:18  
给出一种校正模糊判断矩阵一致性的新方法。首先 ,给出关于模糊判断矩阵满意一致性的定义及判定方法 ,然后通过构造和分析能够反映完全一致性矩阵和原判断矩阵之间关系的偏差矩阵 ,给出校正模糊判断矩阵一致性的计算步骤 ,最后给出了一个算例。  相似文献   

10.
模糊判断矩阵排序向量的确定方法研究   总被引:13,自引:1,他引:12  
首先给出模糊判断矩阵的两种一致性的定义。然后分析现有确定模糊判断矩阵排序向量的方法的特点及存在的问题,在此基础上,系统研究确定模糊判断矩阵排序向量的两类方法,第一类方法是先将模糊判断矩阵转化为AHP判断矩阵,然后将后者的排序向量作为前者的排序向量;另一类方法是直接由一致性或具有满意一致性的模糊判断矩阵计算排序向量。最后用算例说明所提出方法的应用。  相似文献   

11.
Viewing the classical Bernstein polynomials as sampling operators, we study a generalization by allowing the sampling operation to take place at scattered sites. We utilize both stochastic and deterministic approaches. On the stochastic side, we consider the sampling sites as random variables that obey some naturally derived probabilistic distributions, and obtain Chebyshev type estimates. On the deterministic side, we incorporate the theory of uniform distribution of point sets (within the framework of Weyl’s criterion) and the discrepancy method. We establish convergence results and error estimates under practical assumptions on the distribution of the sampling sites.  相似文献   

12.
层次分析法中一致性检验的显著性水平(即判断矩阵偏离一致性的程度)问题在已有研究文献中尚未得到很好的解决。论文在现有一致性指标CI基础上,从随机过程的视角,采用蒙特卡罗模拟法构造一致性指标的随机样本,根据样本确定了显著性水平为0.05和0.01情形下对应的一致性指标的临界值,为评价和调整判断矩阵提供了理论标准。同时,本研究能够确定判断矩阵偏离一致性的程度,并给出决策制定的显著性水平。  相似文献   

13.
模糊判断矩阵的特征向量排序方法   总被引:1,自引:0,他引:1  
从相关性角度提出了互反判断矩阵排序的特征向量方法。利用两类一致性模糊判断矩阵与完全一致性互反判断矩阵的相互转换公式,给出了基于加性一致性指标与乘性一致性指标的模糊判断矩阵特征向量排序方法,最后利用这些方法进行了算例分析,结果表明这些新的排序方法是有效可行的。  相似文献   

14.
根据乘性一致性的定义,从人的主观判断与其权重的函数关系出发,获得了乘性模糊互补判断矩阵的元素表达式,论证了利用乘性模糊互补判断矩阵求取因素相对权重的可行性,最后给出了一种基于乘性一致模糊判断矩阵的排序方法.从而使得乘性模糊互补判断矩阵的应用的理论基础更加坚实.  相似文献   

15.
基于一致性逼近的三角模糊数互补判断矩阵的排序方法   总被引:1,自引:0,他引:1  
研究了元素为三角模糊数形式的互补判断矩阵的一致性和排序问题.分析了三角模糊数互补判断矩阵和三角模糊数互反判断矩阵之间的相互转换关系,提出了这两类判断矩阵完全一致性的概念并得到了三角模糊数互补判断矩阵的元素和排序权值之间的关系,在此基础上建立了一个多目标优化模型,通过求解该模型得到三角模糊数互补判断矩阵的排序向量,利用已有的模糊数比较大小公式得到方案的排序,最后给出了一个算例.  相似文献   

16.
为了解决模糊数间的加和减、乘和除已不再是逆运算的问题,并使得运算法则更加符合客观实际情况,而引入了经典数学中的自变量、因变量、代表系统及自由度等概念,进而对模糊数互补判断矩阵的乘性一致性进行了研究,结果发现若一个模糊数互补判断矩阵满足目前一些文献对其乘性一致性的定义则这个矩阵一定是精确数互补判断矩阵这一不合理之处。文章最后结合模糊集截集理论,利用模糊数互补判断矩阵元素间的关系,重新对乘性一致性模糊数互补判断矩阵进行了定义。  相似文献   

17.
对于满足乘性一致性的残缺互补判断矩阵的决策问题,提出了一种决策方法。首先把互补判断矩阵的乘性一致性定义进行了简化,得到了互补判断矩阵乘性一致性的另外几种表达形式;进一步得到了在已知n-1个特殊元素的条件下,残缺互补判断矩阵中缺失元素的补全方法;然后给出了残缺互补判断矩阵可接受的条件,以及矩阵的一致性检验及调整方法;基于残缺互补判断矩阵,给出了以下决策步骤:残缺互补判断矩阵的一致性检验及调整过程,补全缺失元素的迭代过程和最优方案择优过程。最后给出了一个实例,通过该实例的计算以及本文方法与已有方法的比较,证明了本文方法是简便和有效的。  相似文献   

18.
Inspired by the concept of deviation measure between two linguistic preference relations, this paper further defines the deviation measure of a linguistic preference relation to the set of consistent linguistic preference relations. Based on this, we present a consistency index of linguistic preference relations and develop a consistency measure method for linguistic preference relations. This method is performed to ensure that the decision maker is being neither random nor illogical in his or her pairwise comparisons using the linguistic label set. Using this consistency measure, we discuss how to deal with inconsistency in linguistic preference relations, and also investigate the consistency properties of collective linguistic preference relations. These results are of vital importance for group decision making with linguistic preference relations.  相似文献   

19.
The ordinary least squares estimation is based on minimization of the squared distance of the response variable to its conditional mean given the predictor variable. We extend this method by including in the criterion function the distance of the squared response variable to its second conditional moment. It is shown that this “second-order” least squares estimator is asymptotically more efficient than the ordinary least squares estimator if the third moment of the random error is nonzero, and both estimators have the same asymptotic covariance matrix if the error distribution is symmetric. Simulation studies show that the variance reduction of the new estimator can be as high as 50% for sample sizes lower than 100. As a by-product, the joint asymptotic covariance matrix of the ordinary least squares estimators for the regression parameter and for the random error variance is also derived, which is only available in the literature for very special cases, e.g. that random error has a normal distribution. The results apply to both linear and nonlinear regression models, where the random error distributions are not necessarily known.  相似文献   

20.
In this article, we study the controllability of continuous-time probabilistic logic control networks (CT-PLCNs) under sampled-data feedback controls (SDFCs). First, we demonstrate that the concept of finite-time controllability with probability one for discrete-time probabilistic logic control networks cannot be generalized to CT-PLCNs. Then, we propose the concepts of asymptotical feedback reachability and asymptotical feedback controllability for CT-PLCNs. Based on the invariant subsets, we prove that a target state is asymptotically feedback reachable if and only if the target state is a control equilibrium point and any initial state has an admissible path to the target state. Moreover, we introduce the concept of reachability matrix and propose an easily verifiable criterion for asymptotical feedback reachability expressed in terms of the reachability matrix. Based on these, we prove that a CT-PLCN is asymptotically feedback controllable if and only if every state is a control equilibrium point and there is an admissible path between any pair of initial and target states. The relation between controllability and stabilizability is also discussed. We prove that a CT-PLCN is asymptotically feedback controllable if and only if every state is asymptotically feedback stabilizable. For a controllable CT-PLCN, we propose an algorithm of designing a stabilizing SDFC for any given target state. Additionally, we discuss the asymptotical feedback controllability of CT-PLCNs under time-varying nonuniform SDFCs. Finally, an illustrative example is presented to explain the proposed methods and verify the controllability criteria.  相似文献   

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