The strong uniform convergence of multivariate variable kernel estimates

We show that sup, completely as, where f is a uniformly continuous density on are independent random vectors with common density f, and f_n is the variable kernel estimate Here H_ni is the distance between X_i and its kth nearest neighbour, K is a given density satisfying some regularity conditions, and k is a sequence of integers with the property that log asn     

A review on strong convergence of weighted sums of random elements based on Wasserstein metrics

In a previous paper the authors proposed a simple method to extend results about almost sure convergence for weighted sums of real random variables to the case of Banach-valued random elements. The method arises from the extension of Skorohod's Representation Theorem for weakly convergent sequences due to Blackwell and Dubins, applied to the general framework of weakly equivalent tight sequences of probability measures. This provides a scheme which permits us to handle separately a problem that behaves like the Glivenko-Cantelli Theorem and a question on uniform integrability which generally is reduced to the real valued version of the general problem to be solved.

In this paper we prove that Wasserstein's metrics can play the same role as Skorohod's Representation Theorem in the preceding scheme. We also show that our method can be applied to obtain results with respect to various summability methods (Abel, Euler, …) even in the case in which the ‘weights’ are linear operators.     

收敛函数列的曲线收敛与弧长收敛

本文系统讨论了收敛函数列的曲线收敛与弧长收敛,并给出和证明了弧长收敛的一个性质定理和一个判定定理。     

浅析全概率公式的应用

归蚋总结全概率公式的理解方法、求解问题的分析方法、解题步骤以及应用此公式时应注意的事项等几点教学体会，旨在使学生能够真正理解和掌握全概率公式，从而更好地解决这类实际问题。     

含时滞的单种群反馈控制扩散模型解的渐近行为

本文通过构造 Liapunov 泛函并结合 Smoller 不变区域理论和不等式估计方法,对含时滞的单种群反馈控制扩散模型解的渐近行为进行了讨论,获得了解的整体存在性、有界性及解的一致收敛性的若干充分条件.     

冲突与趋同:世界贸易组织法在欧盟的适用

世界贸易组织(WTO)和欧洲联盟(EU)在贸易法规方面存在着明显的不同。WTO法与欧盟法关系上最有争议的方面就是欧盟否认WTO法的直接适用。一方面,欧洲法院经常主张GATT/WTO法不能在欧洲法律体系内直接适用,法院在许多案件中贯穿了这一原则。但另一方面,当认识到WTO法在一定程度上能约束其成员国尽快融入欧盟法律体系时,欧洲法院在某些案件的处理上又承认WTO法的直接效力。因此,WTO法、欧盟法和成员国国内法之间的冲突不断增加,如何减少冲突日益成为值得关注的问题。     

ESTIMATING THE COMMON MEAN OF A BIVARIATE NORMAL POPULATION

For estimating the common mean of a bivariate normal distribution, Krishnamoorthy & Rohatgi (1989) proposed some estimators which dominate the maximum likelihood estimator in a large region of the parameter space. We consider some modifications of these estimators and study their risk performance.     

云南世界遗产地的旅游审美价值及旅游入境人数分析

云南世界遗产地丽江古城和“三江并流”景点,均具有世界级的旅游审美价值,而且紧紧相邻。但是其入境旅游人数却极为悬殊:前者人满为患,后者游人稀少。导致这种两极化旅游现象的原因很多,其中一个十分重要的原因是中西审美心理差异。为此,不仅应该研究两处世界遗产地的外部旅游环境的平衡、优化问题,而且还应该研究对国内旅游者旅游审美心理的引导问题。     

Irregular Identification,Support Conditions,and Inverse Weight Estimation

In weighted moment condition models, we show a subtle link between identification and estimability that limits the practical usefulness of estimators based on these models. In particular, if it is necessary for (point) identification that the weights take arbitrarily large values, then the parameter of interest, though point identified, cannot be estimated at the regular (parametric) rate and is said to be irregularly identified. This rate depends on relative tail conditions and can be as slow in some examples as n^−1/4. This nonstandard rate of convergence can lead to numerical instability and/or large standard errors. We examine two weighted model examples: (i) the binary response model under mean restriction introduced by Lewbel (1997) and further generalized to cover endogeneity and selection, where the estimator in this class of models is weighted by the density of a special regressor, and (ii) the treatment effect model under exogenous selection (Rosenbaum and Rubin (1983)), where the resulting estimator of the average treatment effect is one that is weighted by a variant of the propensity score. Without strong relative support conditions, these models, similar to well known “identified at infinity” models, lead to estimators that converge at slower than parametric rate, since essentially, to ensure point identification, one requires some variables to take values on sets with arbitrarily small probabilities, or thin sets. For the two models above, we derive some rates of convergence and propose that one conducts inference using rate adaptive procedures that are analogous to Andrews and Schafgans (1998) for the sample selection model.     

论区域产业政策趋同的重要动因——地方政府效用

在区域经济的发展过程中,地方政府之间日益激烈的竞争必然会造成区域之间的产业政策趋同。这对于区域经济的协调发展和长远发展极为不利。化解问题的办法应当靠提高中央政府的宏观调控水平,强化地方政府的责、权、利边界,引导地方政府在区域产业政策中体现差异性。