Summary
The exact formula for the variance of the Index (R) of aggregation of Clark and Evans is derived. Due to the fact that R is a dimensionless number, its variance is independent of population density, being only a function of the sample size and so can be manipulated.
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References
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Petrere, M. The variance of the index (R) of aggregation of Clark and Evans. Oecologia 68, 158–159 (1985). https://doi.org/10.1007/BF00379489
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DOI: https://doi.org/10.1007/BF00379489