OptionalcollationTolerance?: ObjectAssumption<CollationTolerance>The tolerance at which the derived version was collated against the one it is based on. A derivation written before the tolerance was held here states none. Not exported to RDF.
It is an object assumption, so that a tolerance calculated from the scatter of the readings can carry the inference it was drawn by. It is the one quantity in the edition that decides what counts as a reading at all, and a number arrived at by a method should say so.
A derivation names the version another one was derived from, together with the tolerance the two were collated at. How precisely the copies put a symbol depends on what they are and on how their features were obtained, so the tolerance can differ from derivation to derivation.