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1.
In this paper, we consider the laws of large numbers for NSD random variables satisfying Pareto-type distributions with infinite means. Based on the Pareto-Zipf distributions, some weak laws of large numbers for weighted sums of NSD random variables are obtained. Meanwhile, we show that a weak law for Pareto-Zipf distributions cannot be extended to a strong law. Furthermore, based on the two tailed Pareto distribution, a strong law of large numbers for weighed NSD random variables is presented. Our results extend the corresponding earlier ones.  相似文献   
2.
In this paper, we establish the strong law of large numbers and complete convergence for non-identically distributed WOD random variables. We derive some new inequalities of Fuk–Nagaev type for the sums of non-identically distributed WD random variables. All these results further extend and refine previous ones.  相似文献   
3.
从空缺理论的角度,分析形成文化空缺的根源,并从完全空缺、冲突空缺、部分空缺和零空缺四个方面对英汉数字的文 化内涵进行比较研究。每个承载着强烈文化信息的数字在不同文化中都是独一无二的,对数字文化蕴涵的异同性的探究加深 了对英汉文化的理解,有助于感知文化的多样性和差异性,消除跨文化交际中的误解,促进中西方文化交流。  相似文献   
4.
The authors study the strong convergence for sequences of pairwise negatively quadrant dependent (NQD) random variables under some wide conditions, and present some new theorems on the complete convergence and the strong laws of large numbers. The obtained results extend and improve some theorems in existing literature.  相似文献   
5.
Coppi et al. [7 R. Coppi, P. D'Urso, and P. Giordani, Fuzzy and possibilistic clustering for fuzzy data, Comput. Stat. Data Anal. 56 (2012), pp. 915927. doi: 10.1016/j.csda.2010.09.013[Crossref], [Web of Science ®] [Google Scholar]] applied Yang and Wu's [20 M.-S. Yang and K.-L. Wu, Unsupervised possibilistic clustering, Pattern Recognit. 30 (2006), pp. 521. doi: 10.1016/j.patcog.2005.07.005[Crossref], [Web of Science ®] [Google Scholar]] idea to propose a possibilistic k-means (PkM) clustering algorithm for LR-type fuzzy numbers. The memberships in the objective function of PkM no longer need to satisfy the constraint in fuzzy k-means that of a data point across classes sum to one. However, the clustering performance of PkM depends on the initializations and weighting exponent. In this paper, we propose a robust clustering method based on a self-updating procedure. The proposed algorithm not only solves the initialization problems but also obtains a good clustering result. Several numerical examples also demonstrate the effectiveness and accuracy of the proposed clustering method, especially the robustness to initial values and noise. Finally, three real fuzzy data sets are used to illustrate the superiority of this proposed algorithm.  相似文献   
6.
ABSTRACT

The recent evolution of asylum and refugee policies in developed countries has been characterised by two apparently contradictory dynamics. Efforts to limit the number of asylum applicants have coincided with the strengthening of rights for asylum seekers and refugees inside existing protection systems. The ‘numbers vs. rights’ model seeks to explain such counter-veiling trends as a trade-off, as the result of attempts to manage costs within given budget constraints. The model suggests that high numbers of migrants will tend to go hand in hand with attempts to restrict their rights, while low numbers will typically be associated with more rights. This paper provides a critical analysis of the model when applied to asylum and refugee policies and examines its explanatory purchase through the analysis of longitudinal data on visa and asylum statistics. We argue that while the model provides an interesting framework through which to analyse executive decisions in this field, it underestimates the opportunities and constraints provided by the institutional context in which policy choices are made. We argue that ‘over-time’ variation in the influence of non-majoritarian institutions (in Europe, increasingly those operating at the EU level) provide a more compelling account of the dynamics of asylum and refugee policies over time than the political economy predictions of a ‘number vs. rights’ trade-off.  相似文献   
7.
8.
In this paper, we first introduces a tree model without degree boundedness restriction namely generalized controlled tree T, which is an extension of some known tree models, such as homogeneous tree model, uniformly bounded degree tree model, controlled tree model, etc. Then some limit properties including strong law of large numbers for generalized controlled tree-indexed non homogeneous Markov chain are obtained. Finally, we establish some entropy density properties, monotonicity of conditional entropy, and entropy properties for generalized controlled tree-indexed Markov chains.  相似文献   
9.
Due to destructiveness of natural disasters, restriction of disaster scenarios and some human causes, missing data usually occur in disaster decision-making problems. In order to estimate missing values of alternatives, this paper focuses on imputing heterogeneous attribute values of disaster based on an improved K nearest neighbor imputation (KNNI) method. Firstly, some definitions of trapezoidal fuzzy numbers (TFNs) are introduced and three types of attributes (i.e. linguistic term sets, intervals and real numbers) are converted to TFNs. Then the correlated degree model is utilized to extract related attributes to form instances that will be used in K nearest neighbor algorithm, and a novel KNNI method merging with correlated degree model is presented. Finally, an illustrative example is given to verify the proposed method and to demonstrate its feasibility and effectiveness.  相似文献   
10.
We establish a reflection principle for three lattice walkers and use this principle to reduce the enumeration of configurations of three vicious walkers to the enumeration of configurations of two vicious walkers. More precisely, the reflection principle leads to a bijection between three walks (L1, L2, L3) such that L2 intersects both L1 and L3 and three walks (L1, L2, L3) such that L1 intersects L3. Hence we find a combinatorial interpretation of the formula for the generating function for the number of configurations of three vicious walkers, originally derived by Bousquet-Mélou by using the kernel method, and independently by Gessel by using tableaux and symmetric functions. This answers a question posed by Gessel and Bousquet-Mélou. We also find a reflection principle for four vicious walks that leads to a combinatorial interpretation of a formula derived from Gessel's theorem.  相似文献   
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