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Can I read Cosmic Error and the Statistics of Large Scale Structure on EtoBox?

Cosmic Error and the Statistics of Large Scale Structure by Szapudi, István; Colombi, Stéphane is a scholarly article available to read on EtoBox.

What is Cosmic Error and the Statistics of Large Scale Structure about?

We examine the errors on counts in cells extracted from galaxy surveys. The measurement error, related to the finite number of sampling cells, is disentangled from the ``cosmic error'', due to the finiteness of the survey. Using the hierarchical model and assuming locally Poisson behavior, we identified three contributions to the cosmic error: The finite volume effect is proportional to the average of the two-point correlation function over the whole survey. It accounts for possible fluctuations of the density field at scales larger than the sample size. The edge effect is related to the geometry of the survey. It accounts for the fact that objects near the boundary carry less statistical weight than those further away from it. The discreteness effect is due to the fact that the underlying smooth random field is sampled with finite number of objects. This is the ``shot noise'' error. Measurements of errors in artificial hierarchical samples showed excellent agreement with our predictions. The probability distribution of errors is increasingly skewed when the order $N$ and/or the cell size increases. The Gaussian approximation is valid only in the weakly non-linear regime, otherwise

Author
Szapudi, István; Colombi, Stéphane
Published
1995
Language
EN