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[en] Suppose we have a multinormal population with k possible outcomes E1, E2, ..., E/sub k/ and associated probabilities π1, π2, ..., π/sub k/. At each of the independent trials, one of the outcomes is observed. One may be interested in the waiting time for the occurrence of a specified event, which consists of a succession of outcomes. In this paper, we consider the probability distribution of the waiting times associated with specified events, and show how they generalize the Fibonacci, Tribonacci, ..., sequences in different ways. This is possible, since the probability generating functions of the associated waiting time random variables can be utilized to derive the probability distributions
[en] The use of rapidity gaps is proposed as a measure of the spatial pattern of an event. When the event multiplicity is low, the gaps between neighboring particles carry far more information about an event than multiplicity spikes, which may occur very rarely. Two moments of the gap distribution are suggested for characterizing an event. The fluctuations of those moments from event to event are then quantified by an entropy-like measure, which serves to describe erraticity. We use ECOMB to simulate the exclusive rapidity distribution of each event, from which the erraticity measures are calculated. The dependences of those measures on the order q of the moments provide single-parameter characterizations of erraticity. (c) 2000 The American Physical Society
[en] Within the context of a discussion of regular versus chaotic motion in nuclei, several advances in statistical nuclear theory are summarized. They are based on the technique of path integrals serving as generating functions. They relate to statistical spectroscopy and to the statistical theory of nuclear reactions. 25 refs.; 5 figs
[en] The current techniques used for statistical analysis of radioimmunoassays are not very satisfactory for either the statistician or the biologist. They are based on an attempt to make the response curve linear to avoid complicated computations. The present article shows that this practice has considerable effects (often neglected) on the statistical assumptions which must be formulated. A more strict analysis is proposed by applying the four-parameter logistic model. The advantages of this method are: the statistical assumptions formulated are based on observed data, and the model can be applied to almost all radioimmunoassays
[fr]Les techniques couramment utilisees pour effectuer l'analyse statistique des donnees des dosages radioimmunologiques ne sont guere satisfaisantes, ni pour le statisticien, ni pour le biologiste. Elles reposent sur le principe suivant: transformer les donnees afin de lineariser le modele sous-jacent dans le but de se ramener a une regression lineaire. L'article montre que cette pratique a des effets notables (souvent negliges) sur les hypotheses statistiques qui peuvent etre formulees. Une analyse plus stricte est proposee par application d'un modele logistique a 4 parametres. Les avantages de cette methode sont: les hypotheses statistiques formulees sont basees sur des donnees observees et le modele peut etre applique a presque tous les dosages radioimmunologiques
[en] Under the frame of a statistical model, the concept of nonsymmetric entropy which generalizes the concepts of Boltzmann's entropy and Shannon's entropy, is defined. Maximum nonsymmetric entropy principle is proved. Some important distribution laws such as power law, can be derived from this principle naturally. Especially, nonsymmetric entropy is more convenient than other entropy such as Tsallis's entropy in deriving power laws.
[en] The onset of superfluidity in isospin-asymmetric nuclear matter is investigated within the BCS theory. A neutron-proton superfluid state in the channel 3S1-3D1 comes about from the interplay between thermal excitations and separation δμ of the two Fermi surfaces. The superfluid state disappears above the threshold value of the density-asymmetry parameter α=(nn-np)/n≅0.35. For large enough shift between the two Fermi surfaces δμ=(1)/(2)(μn-μp) the transition to the normal state becomes a first-order transition and a second gap solution develops. This solution, however, corresponds to a metastable superfluid state which is unstable with respect to the transition to the normal state. copyright 1997 The American Physical Society
[en] SED being a classical theory, one might consider that the concept of measurement of Classical Physics should apply. However, the following reflections show that such is not the case
[fr]L'EDS etant une theorie classique, on serait tente de lui appliquer les concepts de la mesure de le Physique Classique. Toutefois, les reflexions qui suivent montrent qu'il n'en est rien
[en] We show that contrary to the commonly accepted view, Chapter IX of Gibbs's book  contains the prolegomena to a macroscopic statistical theory that is qualitatively different from his own microscopic statistical mechanics. The formulas obtained by Gibbs were the first results in the history of physics related to the theory of fluctuations in any macroparameters, including temperature. (from the history of physics)
[en] Since data for statistical analysis are always given in a discretized form, observations contain not only measurement errors but also rounding errors which are determined by the discretization step. In this paper we consider situations where the rounding errors are considerable: they are comparable to or even greater (in average) than the measurement errors. It is shown that it can be reasonable to increase the measurement errors in order to reduce the error of the final result.