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1.
本文我们讨论了多周期Probit模型中MLE的存在性问题,给出了当协方差阵已知时,参数的MLE存在的充要条件;当协方差阵未知但具有序列结构时,参数的MLE存在的一个必要条件和一个充分条件. 相似文献
2.
Exceptional Family of Elements for a Variational Inequality Problem and its Applications 总被引:1,自引:0,他引:1
This paper introduces a new concept of exceptional family of elements (abbreviated, exceptional family) for a finite-dimensional nonlinear variational inequality problem. By using this new concept, we establish a general sufficient condition for the existence of a solution to the problem. Such a condition is used to develop several new existence theorems. Among other things, a sufficient and necessary condition for the solvability of pseudo-monotone variational inequality problem is proved. The notion of coercivity of a function and related classical existence theorems for variational inequality are also generalized. Finally, a solution condition for a class of nonlinear complementarity problems with so-called P
* -mappings is also obtained. 相似文献
3.
YU Jianshe & GUO Zhiming College of Mathematics Information Sciences Guangzhou University Guangzhou China 《中国科学A辑(英文版)》2006,49(10):1303-1314
By using the critical point theory, some sufficient conditions for the existence of the solutions to the boundary value problems of a discrete generalized Emden-Fowler equation are obtained. In a special case, a sharp condition is obtained for the existence of the boundary value problems of the above equation. For a linear case, by the discrete variational theory, a necessary and sufficient condition for the existence, uniqueness and multiplicity of the solutions is also established. 相似文献
4.
We introduce consumption externalities into a general equilibrium model with arbitrary consumption sets. To treat the problem of existence of equilibrium, a condition of no unbounded arbitrage, extending the condition of Page (1987) and Page and Wooders (1993, 1996) is defined. It is proven that this condition is sufficient for the existence of an equilibrium and both necessary and sufficient for compactness of the set of rational allocations. 相似文献
5.
Tony E. Smith 《Applied mathematics and computation》1984,15(1):61-69
A sufficient condition is developed for the existence of solutions to complementarity problems, which is applicable to all continuous functions. In addition, it is shown to imply a number of simpler conditions, including the well-known coerciveness condition. Finally, this condition is applied to an existence problem in spatial price equilibrium, where it is shown to yield not only a more general result, but also a simpler method of proof. 相似文献
6.
We formulate a sufficient condition for the existence of a consistent price system (CPS), which is weaker than the conditional full support condition (CFS). We use the new condition to show the existence of CPSs for certain processes that fail to have the CFS property. In particular this condition gives sufficient conditions, under which a continuous function of a process with CFS admits a CPS, while the CFS property might be lost. 相似文献
7.
We prove the existence of classical solutions of elliptic equations of Monge-Ampère type subject to a semilinear oblique
boundary condition which is a perturbation of the Neumann boundary condition. Our techniques also allow us to treat fully nonlinear strictly oblique boundary
conditions satisfying a concavity condition. Examples show that the above restrictions on the boundary condition are generally
necessary for the existence of classical solutions.
Received May 22, 1996 / Accepted April 10, 1997 相似文献
8.
Guihua FeiSoon-Kyu Kim Tixiang Wang 《Journal of Mathematical Analysis and Applications》2002,267(2):665-678
In this paper, we study the existence of periodic solutions for classical Hamiltonian systems without the Palais-Smale condition. We prove that the information of the potential function contained in a finite domain is sufficient for the existence of periodic solutions. Moreover, we establish the existence of infinitely many periodic solutions without any symmetric condition on the potential function V. 相似文献
9.
We present a new sufficient assumption weaker than the classical Ambrosetti–Rabinowitz condition which guarantees the boundedness of (PS) sequences. Moreover, we relax the standard subcritical polynomial growth condition ensuring the compactness of a bounded (PS) sequences. We also revise the Costa–Magalhaes condition [8] to obtain Cerami condition. As a consequence, some existence results derived by minimax methods were proved. Finally, we establish the existence of positive solution under the subcritical polynomial growth condition, while the strong superlinear condition is only required along an unbounded sequence. In other words, a certain degraded oscillation is allowed. 相似文献
10.
The existence of infinitely many subharmonic solutions is obtained for a class of nonautonomous second order Hamiltonian systems with a new superquadratic condition. Furthermore, we can get the existence of homoclinic solutions as the limit of subharmonics under a stronger superquadratic condition which is still weaker than the growth conditions in the references. 相似文献
11.
Z.H. Huang 《Journal of Optimization Theory and Applications》2003,118(3):567-585
By using the concept of exceptional family of elements, Zhao proposed a new existence theorem for variational inequalities over a general nonempty closed convex set (Ref. 1, Theorem 2.3), which is a generalization of the well-known Moré's existence theorem for nonlinear complementarity problems. The proof of Theorem 2.3 in Ref. 1 depends strongly on the condition 0∈K. Since this condition is rather strict for a general variational inequality, Zhao proposed an open question at the end of Ref. 1: Can the condition 0∈K in Theorem 2.3 be removed? In this paper, we answer this open question. Furthermore, we present the new notion of exceptional family of elements and establish a theorem of the alternative, by which we develop two new existence theorems for variational inequalities. Our results generalize the Zhao existence result. 相似文献
12.
《Stochastics An International Journal of Probability and Stochastic Processes》2013,85(3-4):205-216
The well-known theorem of T. Yamada and S. Watanabe asserts that (weak) existence and pathwise uniqueness of the solution of a stochastic equation implies the existence of a strong solution. This is the most powerful tool for proving that a stochastic equation possesses a strong solution. However, pathwise uniqueness is far from being a necessary condition for this. Even if the solution is not unique in law it is also of interest to ask for strong solutions. In the present note, we will discuss in more detail the connection between pathwise uniqueness and the existence of a strong solution. We will state a condition which is not only sufficient but also necessary for the existence of a strong solution. 相似文献
13.
14.
V. M. Veliov 《Set-Valued Analysis》1993,1(3):305-317
Viability theory gives a necessary and sufficient condition for the existence of a (set-valued) state feedback control such that all trajectories of the closed-loop system starting from the graph of a given tube in the state space remain in the tube. Here we investigate the same problem in the case where only incomplete and inexact measurement of the state is available. In the time-invariant case, we give a sufficient condition for the existence of anoutput feedback regulation map. The condition is shown to be equivalent to Haddad's viability condition if the measurement is perfect. 相似文献
15.
Shin-ya Matsushita Wataru Takahashi 《Journal of Mathematical Analysis and Applications》2006,323(2):1354-1364
This paper is devoted to the investigation on the existence of zeros of monotone operators in reflexive Banach spaces. We first present a sufficient condition under which single-valued monotone operators have zeros. The obtained theorem includes a previous result as a special case. A necessary and sufficient condition for the existence of zeros of maximal monotone operators is presented. 相似文献
16.
In this paper, the existence of boundary layer solutions to the Boltzmann equation for hard potential with mixed boundary condition, i.e., a linear combination of Dirichlet boundary condition and diffuse reflection boundary condition at the wall, is considered. The boundary condition is imposed on the incoming particles, and the solution is supposed to approach to a global Maxwellian in the far field. As for the problem with Dirichlet boundary condition (Chen et al., 2004 [5]), the existence of a solution highly depends on the Mach number of the far field Maxwellian. Furthermore, an implicit solvability condition on the boundary data which shows the codimension of the boundary data is related to the number of the positive characteristic speeds is also given. 相似文献
17.
On a sufficient condition for the existence of a common stabilizer for a family of dynamical systems
We consider the problem on the existence of a common stabilizing controller for a finite family of linear vector dynamical
systems. A sufficient condition, obtained on the basis of topological methods, is presented for the existence of a common
stabilizer. Constructive approaches to the development of an algorithm for verifying this condition are indicated. 相似文献
18.
19.
The fol1owing eight kinds of algebraic curves al1 can be the algebraic se-paratrix cycle containing focus for quadratic system, they are the lune fOr-med by hyperbola and equatorial arc['], the entire parabola['], the heterocIinicorbits formed by parabola and straight lineI3], the non-return mapping sepa-ratrix cycle formed by entire e1lipse['], the homoc1inic orbits of cubic curvey' -- 4xs + 3x -- 1 = 0['], the homoc1inic orbits or the non-return mappingseparatrix cycle forrned by quartic cur… 相似文献
20.
关于线性积-微分迁移方程 Neumann 级数解的问题,目前已有许多讨论.本文对一般情况下,带弱边界条件的定态迁移方程非负(正)Neumann 级数解的存在性条件进行更深入的研究,目的不仅仅是给出使方程存在非负(正)解的充分条件,而且还在于探 相似文献