I think that the characteristic not measured in taxonomic classification is EXTINCTION.
Reproduction, structure, behavior, and molecular comparison are the most feasible measurement that is used for taxonomic classification.
Taxonomic classification is defined as hierarchical system is used for classifying organisms to the species level. This classification are the following:
1) domain
2) kingdom
3) phylum
4) subphylum
5) superclass
6) class
7) subclass
8) order
9) family
10) genus
11) species