移动电子商务的运营模式及其应用

发达国家的移动电子商务发展起步较早,而国内引入3G牌照后各方面运营处于转型的模糊时期,尚未完全明确业务和利益分配。根据日本NTT Docomo公司和美国苹果公司的运营经验,国内运营商要具备发展和整合产业价值链优势,必须着手解决交费、安全和标准问题。     

Estimation and Inference Based on Neumann Series Approximation to Locally Efficient Score in Missing Data Problems

Abstract.  Theory on semi-parametric efficient estimation in missing data problems has been systematically developed by Robins and his coauthors. Except in relatively simple problems, semi-parametric efficient scores cannot be expressed in closed forms. Instead, the efficient scores are often expressed as solutions to integral equations. Neumann series was proposed in the form of successive approximation to the efficient scores in those situations. Statistical properties of the estimator based on the Neumann series approximation are difficult to obtain and as a result, have not been clearly studied. In this paper, we reformulate the successive approximation in a simple iterative form and study the statistical properties of the estimator based on the reformulation. We show that a doubly robust locally efficient estimator can be obtained following the algorithm in robustifying the likelihood score. The results can be applied to, among others, parametric regression, marginal regression and Cox regression when data are subject to missing values and the data are missing at random. A simulation study is conducted to evaluate the performance of the approach and a real data example is analysed to demonstrate the use of the approach.     

Boundary bias correction in nonparametric density estimation

An approach for removing boundary bias in nonparametric density esti-mation is considered. The technique is based on suitable finite-dimensional projections in Hilbert space. Applications to boundary bias removal with kernel and trigonometric series estimators are presented.     

论反不正当竞争法中经营者概念的完善

目前理论界和实务界对经营者概念的认识并不一致,导致在司法实践中对一些不正当竞争行为的认定莫衷一是,相似的案件常常因为法官对于经营者概念的不同理解而有不同的判决结果。经营者的概念需要从经济法理论、反不正当竞争法本身、境外法、现行法等多个维度重新审视,只有扩展经营者概念的内涵,才能适应反不正当竞争法的实施的需要。     

用Kantorovich算子的迭代布尔和逼近连续函数

构造了一类Kantorovich算子的迭代布尔和,然后给出了用它逼近连续函数时的正定理、逆定理和非饱和逼近阶的特征刻划.     

影响港口经营人法律地位的因素研究

港口经营人法律地位涉及的内容较为复杂,并且一直是海商法理论和实务中的热点、难点问题。通过选取全新角度,着眼于微观层面,深入研究影响港口经营人法律地位的相关因素,并具体分析港口经营现状、港口作业合同、租船运输方式、运输条款等与港口经营人法律地位的关系,可以切实论证港口经营人法律地位的非单一性。     

SIKKEMA算子与连续模

文献〔1〕给出了Bernstein算子一些新性质 .本文证明Sikkema算子也有类似性质 ,并推广到多元的情况     

Some results on commutation matrices,with statistical applications

The commutation matrix P _mn changes the order of multiplication of a Kronecker matrix product. The vec operator stacks columns of a matrix one under another in a single column. It is possible to express the vec of a Kronecker matrix product in terms of a Kronecker product of vecs of matrices. The commutation matrix plays an important role here. “Super-vec-operators” like vec A ? vec A vec ( A ? A ), and vec{( A ? A ) P _nn} are very convenient. Several of their properties are being studied. Both the traditional commutation matrix and vec operator and the newer concepts developed from these are applied to multivariate statistical and related problems.     

一类混合指数型算子(D)n(f,x)的Lp逼近

给出了一类混合指数型算子Dn(f，x)的Lp逼近意义下的非最优逼近阶的特征刻划．     

失屏,钻穿,电荷效应及电离势计算方法的改进

本文提出了多电子原子及离子体系Ｈａｍｉｌｔｏｎ算符中势函数的新表达式，并由此从Ｓｃｈｒｏｄｉｎｇｅｒ方程出发导出了文献［１０］计算电离势的公式。根据原子光谱实验数据对文献［１０］提出的失屏参数钻穿参数和电荷参数进行了改进。