correlation function

(redirected from Correlation functions)

correlation function

A measure of the clustering on extragalactic scales obtained from redshift surveys. It is the probability for a galaxy to have another neighbor within a given distance of separation, in excess of the probability expected from a uniform random distribution of galaxies, expressed as a function of that distance. Galaxy positions are highly correlated, with the probability decreasing approximately as the inverse square of the galaxy separation. The correlation length for clusters of galaxies is the radius within which the chance of finding another galaxy is double the chance expected from a uniform random distribution of galaxies. Galaxies cluster into groups and clusters on a length-scale of around 30 megaparsecs, whereas superclusters have correlation lengths nearer 130 megaparsecs.
References in periodicals archive ?
For example, Dynamical spin correlation functions, Measured in neutron scattering experiments, Provide signatures of topologically ordered spin liquids.
Analysis of the frequency transfer function (12) for loads with exponential and exponentially-cosine correlation functions shown that it has positive poles of the variable j[omega], therefore, such a system can not be physically realized.
Generally, the correlation functions are used to compare the eigenmodes (or frequencies) obtained by an analytical method with those obtained experimentally.
The conformal weight of the field is a crucial element for expressing the transformation rules of the fields and the symmetries of their correlation functions which are the meaningful objects constructed in the theory because they encode the statistical properties of the theory.
Caption: Figure 5: Sensitivity analysis of PRE for PDE model, G-O model, and white-noise model with various correlation functions.
Figures 1 and 2 represent the correlation functions of the scattering coefficient and scattering efficiency, as functions of [r.
In DLS measurements, the time fluctuation of the scattered light intensity, Is(t), of a dynamic system is recorded, from which the time correlation functions, gl([tau]), of the scattered electric field is accordingly determined [26, 27] and used for extracting the diffusion coefficients of the fast and the slow relaxation modes of PAN solutions using the well-known CONTIN method [28, 29],
Since Gaussian noise is fully characterized by the covariance matrix or the two-body correlation function, any nonvanishing higher-order cumulants or reduced correlation functions are signatures of non-Gaussianity of the probability distribution function (PDF), P(x).
All the correlation functions in this work were fitted by a single stretchedexponentialfunction.
According to (Baklitskiy 2009), the following classification of correlation functions is used in CENS:
Among her topics are probability characteristics of random processes, estimating distribution densities of excursion durations for random stationary broadband signals, using a family of correlation functions of a clipped random process to increase the accuracy of level-crossing parameter estimation, and a methodology for designing adaptable analyzers used to measure the parameters of excursions in stationary random processes.

Full browser ?