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151.
Product probability property, known in the literature as statistical independence, is examined first. Then generalized entropies are introduced, all of which give generalizations to Shannon entropy. It is shown that the nature of the recursivity postulate automatically determines the logarithmic functional form for Shannon entropy. Due to the logarithmic nature, Shannon entropy naturally gives rise to additivity, when applied to situations having product probability property. It is argued that the natural process is non-additivity, important, for example, in statistical mechanics [C. Tsallis, Possible generalization of Boltzmann-Gibbs statistics, J. Stat. Phys. 52 (1988) 479-487; E.G.D. Cohen, Boltzmann and Einstein: statistics and dynamics—an unsolved problem, Pramana 64 (2005) 635-643.], even in product probability property situations and additivity can hold due to the involvement of a recursivity postulate leading to a logarithmic function. Generalized entropies are introduced and some of their properties are examined. Situations are examined where a generalized entropy of order α leads to pathway models, exponential and power law behavior and related differential equations. Connection of this entropy to Kerridge's measure of “inaccuracy” is also explored. 相似文献
152.
S. Wolfling Y. Kantor 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,12(4):569-577
Distribution of loops in a one-dimensional random walk (RW), or, equivalently, neutral segments in a sequence of positive
and negative charges is important for understanding the low energy states of randomly charged polymers. We investigate numerically
and analytically loops in several types of RWs, including RWs with continuous step-length distribution. We show that for long
walks the probability density of the longest loop becomes independent of the details of the walks and definition of the loops.
We investigate crossovers and convergence of probability densities to the limiting behavior, and obtain some of the analytical
properties of the universal probability density.
Received 8 January 1999 相似文献
153.
154.
王金萍 《鞍山科技大学学报》1999,22(1):8-10
提出并检验了双臂侧平举时人体从一支手尖到另一个肩关节的长度与两支手的手尖之间的长度之比依正态分布期望为0618 相似文献
155.
Manoj Chacko P. Yageen Thomas 《Annals of the Institute of Statistical Mathematics》2008,60(2):301-318
Ranked set sampling is applicable whenever ranking of a set of sampling units can be done easily by a judgement method or
based on the measurement of an auxiliary variable on the units selected. In this work, we consider ranked set sampling, in
which ranking of units are done based on measurements made on an easily and exactly measurable auxiliary variable X which is correlated with the study variable Y. We then estimate the mean of the study variate Y by the BLUE based on the measurements made on the units of the ranked set sampling regarding the study variable Y, when (X ,Y) follows a Morgenstern type bivariate exponential distribution. We then consider unbalanced multistage ranked set sampling
and estimate the mean of the study variate Y by the BLUE based on the observations made on the units of multistage ranked set sample regarding the study variable Y. Efficiency comparison is also made on all estimators considered in this work. 相似文献
156.
本文讨论了Von Mises统计量向正态逼近的一致收敛速度问题 ,在核函数仅满足二阶矩条件下 ,给 出了上述收敛速度的上、下界 ,所得结果改进了 [2 ]中相应结论 相似文献
157.
自旋—统计关系与短距离量子场的反常维度 总被引:1,自引:1,他引:0
赵树松 《云南大学学报(自然科学版)》1998,20(4):250-255
相互作用强子的统计与时空维度D,自旋以及短距离量子场的反常维度γBF(gR)有关.使用连续阶导数,就可将泡里定理改写为新的形式.费米强子的实验数据可用反常维度γF(gR)得到解释,而A-D效应应当在实验中观测到. 相似文献
158.
为适应知识经济的发展趋势,企业统计功能,统计对象,统计方法与指标体系也应做出相应的变化和发展,企业人力资源统计有待深化,企业统计指标体系可以知识资本量指标和知识生产指标进行补充。 相似文献
159.
R. Kreißig U. Benedix U.-J. Görke 《Archive of Applied Mechanics (Ingenieur Archiv)》2001,71(2-3):123-134
Summary The presented method to identify material parameters for inelastic deformation laws is based on the numerical analysis of
inhomogeneous stress and strain fields received from suitable experiments. Tensile and bending tests were carried out to obtain
elastic and hardening parameters. The deformation law for small elasto-plastic strains is presented as a system of nonlinear
differential and algebraic equations (DAE) consisting of the stress–strain relation, evolution equations for the internal
variables and the yield condition. Different rules for the evolution equations of isotropic, kinematic and distorsional hardening
are proposed. The DAE are discretized using an implicit Euler method, and the resulting system of nonlinear algebraic equations
is solved using the Newton method. Deterministic optimization procedures are preferred to identify material parameters from
a least-squares functional of numerical and measured comparative quantities. The gradient of the objective function was calculated
using a semianalytical sensitivity analysis. Due to measurement errors, the optimal sets of material parameters are non unique.
The approximate estimation of confidence regions and the calculation of correlation coefficients is presented.
The results of several optimization processes for material parameters of elasto-plastic deformation laws show a good agreement
between measured and calculated values, but they show also problems which may occur if systematic errors will not be recognized
and deleted.
Received 30 September 1999; accepted for publication 8 March 2000 相似文献
160.
J. Török S. Krishnamurthy J. Kertész S. Roux 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,18(4):697-701
We introduce a model for the slow relaxation of an energy landscape caused by its local interaction with a random walker whose
motion is dictated by the landscape itself. By choosing relevant measures of time and potential this self-quenched dynamics can be mapped on to the “True” Self-Avoiding Walk model. This correspondence reveals that the average distance of
the walker at time t from its starting point is , where for one dimension and 1/2 for all higher dimensions. Furthermore, the evolution of the landscape is similar to that in growth
models with extremal dynamics.
Received 8 August 2000 相似文献