Conclusion and summary
As theI σ-index is neither affected by the mean per sample unit except for regular distribution nor standing on the assumption of any definite type of contagious distribution, it may have the most wide range of application among the ones hitherto deviced for measuring the dispersion of individuals in a population. The relations of theI σ-index to\(V/\bar x\),k of negative binomial distribution andN of binomial distribution as well as the new dispersion index,I B , given in this paper may serve, if necessary, for the analysis of data in the ecological works.
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Aided by the Scientific Research Fund from the Ministry of Education.
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Morisita, M. I σ-Index, a measure of dispersion of individuals. Res Popul Ecol 4, 1–7 (1962). https://doi.org/10.1007/BF02533903
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DOI: https://doi.org/10.1007/BF02533903