HOMOPLASY AND THE CHOICE AMONG CLADOGRAMS

@article{Goloboff1991HOMOPLASYAT,
  title={HOMOPLASY AND THE CHOICE AMONG CLADOGRAMS},
  author={Pablo A. Goloboff},
  journal={Cladistics},
  year={1991},
  volume={7}
}
  • P. Goloboff
  • Published 1 September 1991
  • Economics
  • Cladistics
Abstract Cladistic data are more decisive when the possible trees differ more in tree length. When all the possible dichotomous trees have the same length, no one tree is better supported than the others, and the data are completely undecisive. From a rule for recursively generating undecisive matrices for different numbers of taxa, formulas to calculate consistency, rescaled consistency and retention indices in undecisive matrices are derived. The least decisive matrices are not the matrices… 

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The relationship between homoplasy and the degree to which a data set provides information to choose among the possible trees is analysed, and a statistic, Data Decisiveness, DD is proposed to measure decisiveness.

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