The unique solution of the Karcher equation and the self-adjointness of the Karcher mean

Lawson and Lim showed that the Karcher equation for positive invertible operators on a Hilbert space has a unique solution using the method of the implicit function theorem of a Banach space. In this paper, in the framework of the operator inequality, we show the equivalence of the unique solution of the Karcher equation and the self-adjointness of the Karcher mean. For this, we reform the notion of the operator power means of negative order by virtue of the Tsallis relative operator entropy of negative order.     

加权AM-GM-HM不等式链的加细

在一定条件下得到加权的算术平均、几何平均和调和平均不等式链的一种加细形式,并由此推出加权的 ｋｙ Ｆａｎ 不等式和王王不等式．此外,还给出一个连接并且分离加权算术平均和加权调和平均的单调连续函数     

Matrix Wielandt inequality via the matrix geometric mean

In this paper, by virtue of the matrix geometric mean and the polar decomposition, we present new Wielandt type inequalities for matrices of any size. To this end, based on results due to J.I. Fujii, we reform a matrix Cauchy–Schwarz inequality, which differs from ones due to Marshall and Olkin. As an application, we show a new block matrix version of Wielandt type inequalities under the block rank additivity condition.     

凸函数的算子凸性估计及其在算子平均中的应用(英文)

本文利用Mond-Peari方法对凸函数的n个算子凸性进行了比式估计.在此基础上,得到了n个代数平均的幂与n个算子的幂的代数平均的比较,n个算子的几何平均的幂与n个算子的幂的几何平均的比较.特别地,文中还给出了代数平均和混序几何平均.     

正定自共轭四元数矩阵的均值

本文引进了两个正定自共轭四元数矩阵的算术均值，几何均值，调和均值三概念，给出了正定自共轭四元数矩阵的算术－几何－调和均值不等式，得到了正定自共轭四元数矩阵的几何均值的一个最大性质及其相关的某些性质．     

衡量互反矩阵一致性的一种新指标

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。     

A matrix reverse Hölder inequality

A matrix reverse Hölder inequality is given. This result is a counterpart to the concavity property of matrix weighted geometric means. It extends a scalar inequality due to Gheorghiu and contains several Kantorovich type inequalities.     

Weighted isoperimetric inequalities in warped product manifolds

We prove some sharp isoperimetric type inequalities in warped product manifolds, or more generally, multiply warped product manifolds. We also relate them to inequalities involving the higher order mean-curvature integrals. Applications include some sharp eigenvalue estimates, Pólya-Szegö inequality, Faber-Krahn inequality, Sobolev inequality and some sharp geometric inequalities in some warped product spaces.     

Principal powers of matrices with positive definite real part

We study principal powers of complex square matrices with positive definite real part, or with numerical range contained in a sector. We extend the notion of geometric mean to such matrices and we establish an operator norm bound in this context.     

Geometric means of structured matrices

The geometric mean of positive definite matrices is usually identified with the Karcher mean, which possesses all properties—generalized from the scalar case—a geometric mean is expected to satisfy. Unfortunately, the Karcher mean is typically not structure preserving, and destroys, e.g., Toeplitz and band structures, which emerge in many applications. For this reason, the Karcher mean is not always recommended for modeling averages of structured matrices. In this article a new definition of a geometric mean for structured matrices is introduced, its properties are outlined, algorithms for its computation, and numerical experiments are provided. In the Toeplitz case an existing mean based on the Kähler metric is analyzed for comparison.     

杨-张不等式的推广及其应用

本文利用杨路和张景中创造的特征根的方法和Darboux定理,将著名的杨-张不等式推广到n维欧氏空间的两个完全同向的有限质点组中,获得了有限质点组的一类几何不等式,作为其应用,给出了一些新的三角形不等式.     

Refined Heinz operator inequalities

Motivated by the well-known Heinz norm inequalities, in this article we study the corresponding Heinz operator inequalities. We derive the whole series of refinements of these operator inequalities, first with the help of the well-known Hermite–Hadamard inequality, and then, utilizing the parametrized family of the so-called Heron means. In such a way, we obtain improvements of some recent results, known from the literature.     

How to derive priorities in AHP: a comparative study

A heated discussion has arisen over the “best” priorities derivation method. Using a Monte Carlo simulation this article compares and evaluates the solutions of four AHP ratio scaling methods: the right eigenvalue method, the left eigenvalue method, the geometric mean and the mean of normalized values. Matrices with different dimensions and degree of impurities are randomly constructed. We observe a high level of agreement between the different scaling techniques. The number of ranking contradictions increases with the dimension of the matrix and the inconsistencies. However, these contradictions affect only close priorities.     

Norm inequalities in operator ideals

In this paper we introduce a new technique for proving norm inequalities in operator ideals with a unitarily invariant norm. Among the well-known inequalities which can be proved with this technique are the Löwner-Heinz inequality, inequalities relating various operator means and the Corach-Porta-Recht inequality. We prove two general inequalities and from them we derive several inequalities by specialization, many of them new. We also show how some inequalities, known to be valid for matrices or bounded operators, can be extended with this technique to normed ideals in C^∗-algebras, in particular to the noncommutative Lp-spaces of a semi-finite von Neumann algebra.     

Ando–Hiai type inequalities for multivariate operator means

ABSTRACT

We present several Ando–Hiai type inequalities for n-variable operator means for positive invertible operators. Ando–Hiai's inequalities given here are not only of the original type but also of the complementary type and of the reverse type involving the generalized Kantorovich constant.     

On the Ky Fan inequality

Some inequalities related to the Ky Fan and Wang inequalities for weighted arithmetic and geometric means are given.     

Norm inequalities related to the arithmetic–geometric mean inequalities for positive semidefinite matrices

In this paper, we propose three new matrix versions of the arithmetic–geometric mean inequality for unitarily invariant norms, which stem from the fact that the Heinz mean of two positive real numbers interpolates between the geometric and arithmetic means of these numbers. Related trace inequalities are also presented.     

Generalized power means and interpolating inequalities

In this paper, we introduce a multi-parameter family of generalized power means, and use their special properties to provide a new method of interpolating inequalities. We give a different refinement of an inequality of Ky Fan as a particular application of our method.

     

AHP中不一致判断矩阵调整方法的改进

针对AHP中不一致性判断矩阵,提出了一种新的调整方法.通过分析诱导矩阵与判断矩阵之间的关系,用元素的几何平均值对矩阵中偏差最大的元素逐个修正,直到判断矩阵达到满意的一致性.该算法利用原始判断信息修正单个元素,提高了判断矩阵修正速度,简洁、实用.