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Measurement of non-randomness in spatial distributions


The measurement of departure from randomness in spatial distributions has widespread application in ecological work. Several “indices of non-randomness” are compared with regard to their dependence on sample number, sample size and density. Criteria for the best choice of index for specific situations are discussed. A new coefficientC x is proposed for use with positively contagious distributions and tests of significance are given. WhenC x and another index (S 2/m−1) are used for positive and negative contagion respectively, values ranging from −1 through 0 (random) to +1 are obtained, regardless of sample number, sample size or density.

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Green, R.H. Measurement of non-randomness in spatial distributions. Res Popul Ecol 8, 1–7 (1966).

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  • Negative Binomial Distribution
  • Negative Contagion
  • Larval Insect
  • Australia Introduction
  • Positive Contagion