Summary
A method is presented for calculating the discriminative value of qualitative descriptors, based on the number of taxa pairs that a certain descriptor can separate and on the amount of information that this descriptor shares with other descriptors of the same study. To make this method compatible with the calculation of the discriminative power of quantitative characteristics, statistical tests are proposed to enable a comparison between both types of characteristics. The data from 32 cacao clones are used to demonstrate the methodology for 15 qualitative characteristics of leaves, flowers and fruits of the cacao tree. The combined use of qualitative and quantitative descriptors in the calculation of their respective discriminatory power is also presented.
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Engels, J.M.M. A systematic description of cacao clones. II. The discriminative value of qualitative characteristics and the practical compatability of the discriminative value of quantitative and qualitative descriptors. Euphytica 32, 387–396 (1983). https://doi.org/10.1007/BF00021447
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DOI: https://doi.org/10.1007/BF00021447