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A Count Probability Cookbook: Spurious Effects and the Scaling Model

S. Colombi·F. R. Bouchet·R. Schaeffer
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Abstract

We study the errors brought by finite volume effects and dilution effects on the practical determination of the count probability distribution function P_N(n,L), which is the probability of having N objects in a cell of volume L^3 for a set of average number density n. Dilution effects are particularly relevant to the so-called sparse sampling strategy. This work is mainly done in the framework of the scaling model (Balian \& Schaeffer 1989), which assumes that the Q-body correlation functions obey the scaling relation xi_Q(K r_1,..., K r_Q) = K^{-(Q-1) gamma} xi_N(r_1,..., r_Q). We use three synthetic samples as references to perform our analysis: a fractal generated by a Rayleigh-Lévy random walk with 3.10^4 objects, a sample dominated by a spherical power-law cluster with 3.10^4 objects and a cold dark matter (CDM) universe involving 3.10^5 matter particles.

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S. Colombi, F. R. Bouchet, R. Schaeffer. 1994-09-21. A Count Probability Cookbook: Spurious Effects and the Scaling Model. https://doi.org/10.1086/192125

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