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901.
FANG Yixin JIN Man & ZHAO Lincheng Department of Statistics Finance University of Science Technology of China Hefei China 《中国科学A辑(英文版)》2005,48(2):155-168
A regression model with a nonnegativity constraint on the dependent variable, known as censored median regression model, is considered. Under some mild conditions, the LAD estimate of the regression coefficient is shown to be strongly consistent. Furthermore, its convergence rate and Bahadur strong representation are also obtained. 相似文献
902.
WU Mixia & WANG Songgui College of Applied Sciences Beijing University of Technology Beijing China 《中国科学A辑(英文版)》2005,48(11):1451-1464
For the mixed effects models with balanced data, a new ordering of design matrices of random effects is defined, and then a simple formula of the spectral decomposition of covariance matrix is obtained. To compare with the two methods in literature, the decomposition can not only give the actual number of all distinct eigenvalues and their expression, but also show clearly the relationship between the design matrices of random effects and the decomposition. These results can be applied to the problems for testifying the analysis of the variance estimate being a minimum variance unbiased under all random effects models and some mixed effects models with balanced data, for finding the explicit solution of maximum likelihood equations for the general mixed effects model and for showing the relationship between the spectral decomposition estimate and the analysis of variance estimate. 相似文献
903.
In this paper, necessary and sufficient conditions are given for the weighted composition operator T
ψ,φ to be bounded or compact from the space βμ to βυ (or βμ,0 to β
υ,0)on the unit ball of C
rn. At the same time, a series of corollaries are also obtained. 相似文献
904.
We prove existence and uniqueness results for non-linear elliptic equations with lower order terms, L1 data, and mixed boundary conditions that include as particular cases the Dirichlet and the Neumann problems.
Mathematics Subject Classification (2000) 35J25, 35D05, 35J70, 35J60 相似文献
905.
L. Yu. Cherednikova 《Mathematical Notes》2005,77(5-6):715-725
Suppose that
is a system of continuous subharmonic functions in the unit disk
and
is the class of holomorphic functions f in
such that log|f(z)| ≤ B
f
p
f
(z) + C
f
, z ∈
, where B
f
and C
f
are constants and p
f
∈
. We obtain sufficient conditions for a given number sequence Λ = { λn} ⊂
to be a subsequence of zeros of some nonzero holomorphic function from
, i.e., Λ is a nonuniqueness sequence for
.__________Translated from Matematicheskie Zametki, vol. 77, no. 5, 2005, pp. 775–787.Original Russian Text Copyright ©2005 by L. Yu. Cherednikova. 相似文献
906.
In this article, mixture distributions and weighted likelihoods are derived within an information-theoretic framework and
shown to be closely related. This surprising relationship obtains in spite of the arithmetic form of the former and the geometric
form of the latter. Mixture distributions are shown to be optima that minimize the entropy loss under certain constraints.
The same framework implies the weighted likelihood when the distributions in the mixture are unknown and information from
independent samples generated by them have to be used instead. Thus the likelihood weights trade bias for precision and yield
inferential procedures such as estimates that can be more reliable than their classical counterparts. 相似文献
907.
Fu-Chuen Chang 《Annals of the Institute of Statistical Mathematics》2005,57(4):833-844
This paper is concerned with the problem of computing approximateD-optimal design for polynomial regression with analytic weight function on a interval [m
0-a,m
0+a]. It is shown that the structure of the optimal design depends ona and weight function. Moreover, the optimal support points and weights are analytic functions ofa ata=0. We make use of a Taylor expansion to provide a recursive procedure for calculating theD-optimal designs. 相似文献
908.
This paper presents two facility location models for the problem of determining how to optimally serve the requirements for communication circuits between the United States and various European and Middle Eastern countries. Given a projection of future requirements, the problem is to plan for the economic growth of a communications network to satisfy these requirements. Both satellite and submarine cable facilities may be used. The objective is to find an optimal placement of cables (type, location, and timing) and the routing of individual circuits between demand points (over both satellites and cables) such that the total discounted cost over a T-period horizon is minimized. This problem is cast as a multiperiod, capacitated facility location problem. Two mathematical models differing in their provisions for network reliability are presented. Solution approaches are outlined and compared by means of computational experience. Use of the models both in planning the growth of the network and in the economic evaluation of different cable technologies is also discussed. 相似文献
909.
H.Joseph Newton 《Journal of multivariate analysis》1978,8(2):317-323
Closed form matrix equations are given for the information matrix of the parameters of the vector mixed autoregressive moving average time series model. 相似文献
910.
Activity coefficients for CHl in the system HCl+NiCl
2
+H
2
O at 298.15°K at constant total ionic strengths of 0.1, 0.5, 1.0, 2.0, and 3.0 moles-kg
–1
have been determined by an emf method. A comparison was made between Scatchard's and Pitzer's interpretations of mixed-electrolyte solutions for this system and six related systems. Preference can be given to Pitzer's method provided cognizance is taken of the effects of higher-order electrostatic terms beyond the Debye-Hückel approximation on the thermodynamic properties of asymmetrical mixtures. 相似文献