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31.
We introduce a random perturbed version of the classical fidelity and we show that it converges with the same rate of decay
of correlations, but not uniformly in the noise. This makes the classical fidelity unstable in the zero-noise limit. 相似文献
32.
We derive a moderate deviation principle for the lower tail probabilities of the length of a longest increasing subsequence in a random permutation. It refers to the regime between the lower tail large deviation regime and the central limit regime. The present article together with the upper tail moderate deviation principle in Ref. 12 yields a complete picture for the whole moderate deviation regime. Other than in Ref. 12, we can directly apply estimates by Baik, Deift, and Johansson, who obtained a (non-standard) Central Limit Theorem for the same quantity. 相似文献
33.
Robert J. Rubin 《Journal of statistical physics》1991,65(5-6):1207-1216
A one-dimensional lattice random walk in the presence ofm equally spaced traps is considered. The step length distribution is a symmetric exponential. An explicit analytic expression is obtained for the probability that the random walk will be trapped at thejth trapping site. 相似文献
34.
研究了平面上系数{Xn,n≥0}为(?)-混合序列在满足,(q>1)等条件下的随机级数的增长性及值分布,得到了比较好的结果. 相似文献
35.
We apply a Bayesian approach to the problem of prediction in an unbalanced growth curve model using noninformative priors. Due to the complexity of the model, no analytic forms of the predictive densities are available. We propose both approximations and a prediction-oriented Metropolis-Hastings sampling algorithm for two types of prediction, namely the prediction of future observations for a new subject and the prediction of future values for a partially observed subject. They are illustrated and compared through real data and simulation studies. Two of the approximations compare favorably with the approximation in Fearn (1975, Biometrika, 62, 89–100) and are very comparable to the more accurate Rao-Blackwellization from Metropolis-Hastings sampling algorithm. 相似文献
36.
Stanislav Volkov 《Journal of Theoretical Probability》2006,19(3):691-700
Vertex-reinforced random walk is a random process which visits a site with probability proportional to the weight w
k
of the number k of previous visits. We show that if w
k
∼ k
α, then there is a large time T
0 such that after T
0 the walk visits 2, 5, or ∞ sites when α < 1, = 1, or > 1, respectively. More general results are also proven.
相似文献
37.
Silvia Vogel 《Annals of Operations Research》2006,142(1):269-282
The paper considers upper semicontinuous behavior in distribution of sequences of random closed sets. Semiconvergence in distribution
will be described via convergence in distribution of random variables with values in a suitable topological space. Convergence
statements for suitable functions of random sets are proved and the results are employed to derive stability statements for
random optimization problems where the objective function and the constraint set are approximated simultaneously.
The author is grateful to two anonymous referees for helpful suggestions. 相似文献
38.
引进了随机环境中多物种分枝随机游动的一般模型.在分枝过程非灭绝的情况下,讨论了系统的状态分类,得到了系统暂留及强常返的充要条件是存在k个定义在整数集上的函数分别满足某种性质.最后给出了系统强暂留的充分条件. 相似文献
39.
The bond random mixed compound Fe(Br0.9I0.1)2 has been studied by magnetization and Mössbauer measurements. Although the zero-field cooled and field-cooled magnetization variations are not like a typical spin glass one, the Mössbauer spectrum below Néel temperature shows a hyperfine field distribution. It implies that the 10% FeI2 mixed in FeBr2 can be induced by the bond random effect which causes the sample to exhibit a spin glass-like behavior. 相似文献
40.
Jian Ming ZHAN Bijan DAVVAZ K. P. SHUM 《数学学报(英文版)》2007,23(8):1345-1356
We describe the relationship between the fuzzy sets and the algebraic hyperstructures. In fact, this paper is a continuation of the ideas presented by Davvaz in (Fuzzy Sets Syst., 117: 477- 484, 2001) and Bhakat and Das in (Fuzzy Sets Syst., 80: 359-368, 1996). The concept of the quasicoincidence of a fuzzy interval value with an interval-valued fuzzy set is introduced and this is a natural generalization of the quasi-coincidence of a fuzzy point in fuzzy sets. By using this new idea, the concept of interval-valued (α,β)-fuzzy sub-hypermodules of a hypermodule is defined. This newly defined interval-valued (α,β)-fuzzy sub-hypermodule is a We shall study such fuzzy sub-hypermodules and sub-hypermodules of a hypermodule. generalization of the usual fuzzy sub-hypermodule. consider the implication-based interval-valued fuzzy 相似文献