Glossary of "Cladistics (2nd ed.)" by Kitching et al. (1998)
- A data set that includes all possible informative characters in equal numbers so that it is phylogenetically uninformative. Undecisive data yields all possible fully resolved cladograms, which will all be of the same length, and thus offer no reason for choosing some cladograms in preference to others. Cf. decisive data.
- 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.