Permutation tail probability test
permutation tail probability (PTP) test
Glossary of "Cladistics (2nd ed.)" by Kitching et al. (1998)
- A procedure that attempts to assess the degree of cladistic covariation in a data set by permuting the states of each character and randomly reassigning them to the ingroup taxa in such a way that the proportions of each state are maintained. This process is repeated to produce a large number of such pseudoreplicate data sets, which are then analysed cladistically. The PTP is defined as the proportion of all data sets (permuted plus original) that yield cladograms equal to or shorter than those produced from the original data set.
- Kitching, I. J., Forey, P. L. Humphries, C. J. & Williams, D. M. 1998. Cladistics, 2nd ed.: the Theory and Practice of Parsimony Analysis. -xii + 228 pp. Oxford University Press, New York.