Parametric Families of Multivariate Distributions with Given Margins

Parametric families of continuous bivariate distributions with given margins that include independence and perfect positive dependence are compared on the basis on some important properties. Since many such families exist, the comparisons are helpful for deciding on suitable models for multivariate data. The study of the properties has motivation from applications in extreme value inference. One property considered for bivariate families is whether they extend to multivariate families, and extensions are given when possible. Several new bivariate and multivariate families are included and some open research problems in the area of multivariate families are mentioned.     

On weighted Shapley values

Nonsymmetric Shapley values for coalitional form games with transferable utility are studied. The nonsymmetries are modeled through nonsymmetric weight systems defined on the players of the games. It is shown axiomatically that two families of solutions of this type are possible. These families are strongly related to each other through the duality relationship on games. While the first family lends itself to applications of nonsymmetric revenue sharing problems the second family is suitable for applications of cost allocation problems. The intersection of these two families consists essentially of the symmetric Shapley value. These families are also characterized by a probabilistic arrival time to the game approach. It is also demonstrated that lack of symmetries may arise naturally when players in a game represent nonequal size constituencies.     

On the Stability of the Feasible Set in Linear Optimization

This paper deals with the stability of two families of linear optimization problems, each one formed by the dual problems to the members of the other family. We characterize the problems of these families that are stable in the sense that they remain consistent (inconsistent) under sufficiently small arbitrary perturbations of all the data. This characterization is established in terms of the lower semicontinuity property of the feasible set mapping and the boundedness of the optimal set of the corresponding coupled problem. Other continuity properties of the feasible set mapping are also derived. This stability theory extends some well-known theorems of Williams and Robinson on the stability of ordinary linear programming problems to linear optimization problems with infinitely many variables or constraints.     

完全二阶抽象柯西问题的温和C-存在族和解空间

本文中,我们定义了完全二阶抽象柯西问题的温和C-存在族.对指数有界的温和C-存在族,我们还给出了温和C-存在族的Hille-Yosida型的充要条件.对不完全二阶抽象柯西问题,我们定义了解空间和Hille-Yosida空间,我们还证明了不完全二阶抽象柯西问题在其Hille-Yosida空间上是自动适定的,把deLaubenfels文中关于一阶抽象柯西问题的相应结果推广到了二阶的情形.     

Two block hybrid projection method for solving a common solution for a system of generalized equilibrium problems and fixed point problems for two countable families

In this paper, we introduce a new iterative sequence which is constructed by using the new modified two block hybrid projection method for solving the common solution problem for a system of generalized equilibrium problems of inverse strongly monotone mappings and a system of bifunctions satisfying certain conditions, and the common fixed point problems for families of uniformly quasi - ${\phi}$ - asymptotically nonexpansive and locally uniformly Lipschitz continuous. Strong convergence theorems are proved on approximating a common solution of a system of generalized equilibrium problems and fixed point problems for two countable families in Banach spaces. Our results presented in this paper improve and extend many recent results in this area.     

Complexity of Recognizing Equal Unions in Families of Sets

A family of sets has the equal union property if there exist two nonempty disjoint subfamilies having equal unions and has the full equal union property if, in addition, all sets are included. Both recognition problems are NP-complete even when restricted to families for which the cardinality of every set is at most three. Both problems can be solved in polynomial time when restricted to families having a bounded number of sets with cardinality greater than two. A corollary is that deciding if a graph has two disjoint edge covers is in P.     

Conjugate distributions in statistical problems with nuisance parameters

Developing the concept of distributions that are conjugate to a given likelihood function of an unknown parameter in statistical problems of the Bayesian kind, we introduce the notion of locally conjugate distribution families. We investigate some properties of conjugate and locally conjugate families, which are then applied to analytic elimination of the nuisance parameters. The potentialities of this approach are compared with those of the well-known approach related to naturally conjugate distributions. To illustrate the results obtained, we solve a series of known statistical problems. Proceedings of the Seminar on Stability Problems for Stochastic Models. Moscow, Russia, 1996, Part II.     

Koszul cohomology for finite families of comodule maps and applications

The Koszul cohomology for finite families of comodule endomorphisms is used to study finite families of polynomials with operator coefficients. In particular, we consider multiparameter eigenvalue problems.     

Comparative evaluation of MILP flowshop models

This paper investigates the performance of two families of mixed-integer linear programing (MILP) models for solving the regular permutation flowshop problem to minimize makespan. The three models of the Wagner family incorporate the assignment problem while the five members of the Manne family use pairs of dichotomous constraints, or their mathematical equivalents, to assign jobs to sequence positions. For both families, the problem size complexity and computational time required to optimally solve a common set of problems are investigated. In so doing, this paper extends the application of MILP approaches to larger problem sizes than those found in the existing literature. The Wagner models require more than twice the binary variables and more real variables than do the Manne models, while Manne models require more constraints for the same sized problems. All Wagner models require much less computational time than any of the Manne models for solving the common set of problems, and these differences increase dramatically with increasing number of jobs and machines. Wagner models can solve problems containing larger numbers of machines and jobs than the Manne models, and hence are preferable for finding optimal solutions to the permutation flowshop problem with makespan objective.     

Inner Regularizations and Viscosity Solutions for Pessimistic Bilevel Optimization Problems

Pessimistic bilevel optimization problems are not guaranteed to have a solution even when restricted classes of data are involved. Thus, we propose a concept of viscosity solution, which satisfactorily obviates the lack of optimal solutions since it allows to achieve in appropriate conditions the security value. Differently from the viscosity solution concept for optimization problems, introduced by Attouch (SIAM J Optim 6:769–806, 1996) and defined through a viscosity function that aims at regularizing the objective function, viscosity solutions for pessimistic bilevel optimization problems are defined through regularization families of the solutions map to the lower-level optimization. These families are termed “inner regularizations” since they approach the optimal solutions map from the inside. First, we investigate, in Banach spaces, several classical regularizations of parametric constrained minimum problems giving sufficient conditions for getting inner regularizations; then, we establish existence results for the corresponding viscosity solutions under possibly discontinuous data.     

The part families problem in flexible manufacturing systems

Parts grouping into families can be performed in flexible manufacturing systems (FMSs) to simplify two classes of problems: long horizon planning and short horizon planning. In this paper the emphasis is on the part families problem applicable to the short horizon planning. Traditionally, parts grouping was based on classification and coding systems, some of which are reviewed in this paper. To overcome the drawbacks of the classical approach to parts grouping, two new methodologies are developed. The methodologies presented are very easy to implement because they take advantage of the information already stored in the CAD system. One of the basic elements of this system is the algorithm for solving the part families problem. Some of the existing clustering algorithms for solving this problem are discussed. A new clustering algorithm has been developed. The computational complexity and some of the computational results of solving the part families problem are also discussed.     

Iterative processes for common fixed points of two different families of mappings with applications

In this paper, an implicit iterative process is investigated for common fixed points of two different families of nonlinear mappings. Theorems of strong and weak convergence are established in real Hilbert spaces. As an application of the iterative process, inclusion problems are considered.     

Modified Chebyshev-Halley type method and its variants for computing multiple roots

We present two families of third order methods for finding multiple roots of nonlinear equations. One family is based on the Chebyshev-Halley scheme (for simple roots) and includes Halley, Chebyshev and Chun-Neta methods as particular cases for multiple roots. The second family is based on the variant of Chebyshev-Halley scheme and includes the methods of Dong, Homeier, Neta and Li et al. as particular cases. The efficacy is tested on a number of relevant numerical problems. It is observed that the new methods of the families are equally competitive with the well known special cases of the families.     

One-Parametric Linear-Quadratic Optimization Problems

We consider families of optimization problems with quadratic object function and affine linear constraints, which depend smoothly on one real parameter. For a generic subclass of such problems only three different types of (generalized) critical points occur, whereas in the general case (of nonlinear one-parameter families of constrained optimization problems on R ⁿ ) five types are to be distinguished. We clarify the theoretical background of these phenomena and illustrate the underlying mechanism with simple examples.     

On Extremal Decomposition Problems in Families of Systems of Domains of General Type

We prove a theorem extending results of the theory of extremal decomposition problems to families of systems of domains of general type. The considered families of systems of domains contain domains similar in the small to end and strip domains of a quadratic differential having poles of arbitrary orders n _k 3 at some marked points c_k, k = 1,...,p. In this case, we give a simple definition of reduced modules for the considered systems of domains. Some other definitions for the treated systems of domains are also considered. Some examples are given illustrating the possibilities of applications of the theorem obtained in the problems on extremal decomposition. Bibliography: 13 titles.     

Axially Symmetric Deformations of Fibre-reinforced Cylinders

General solutions are obtained for boundary-value problems givingaxially symmetric deformations of "ideal" fibre-reinforced cylinders.The cylinders are hollow, thick-walled and elastic, and arecontinuously reinforced throughout by two families of helicalfibres making an angle ±ø with the axis of symmetry.We consider traction boundary-value problems and in particularobtain two fundamental solutions corresponding to axial andradial concentrated loadings. The theory is applied to the problemof inflation of the cylinder under uniform internal pressure.     

Numerical study of the HP version of mixed discontinuous finite element methods for reaction‐diffusion problems: The 1D case

This article studies the stability and convergence of the hp version of the three families of mixed discontinuous finite element (MDFE) methods for the numerical solution of reaction‐diffusion problems. The focus of this article is on these problems for one space dimension. Error estimates are obtained explicitly in the grid size h, the polynomial degree p, and the solution regularity; arbitrary space grids and polynomial degree are allowed. These estimates are asymptotically optimal in both h and p for some of these methods. Extensive numerical results to show convergence rates in h and p of the MDFE methods are presented. Theoretical and numerical comparisons between the three families of MDFE methods are described. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 525–553, 2003     

Multiple Solutions of Nonlinear Boundary-Value Problems

A class of nonlinear boundary-value problems containing a parameter is studied analytically and numerically. It is shown that under certain circumstances there are two families of solutions when the parameter tends to zero; one family comprises small solutions and is obtained by regular perturbations, while the other family comprises finite solutions incorporating boundary and interior layers. It is shown by numerical integration that the two families are smooth continuations of each other when the parameter passes through finite values.     

Inverse problems of the Erdős-Ko-Rado type theorems for families of vector spaces and permutations

Science China Mathematics - Ever since the famous Erdős-Ko-Rado theorem initiated the study of intersecting families of subsets, extremal problems regarding intersecting properties of families...