Stability of comparative evaluation —Example: Environmental databases

For comparative evaluations, the theory of partially ordered sets and its visualisation tool, the Hasse diagram technique, is often useful. The results depend on the used set of characteristic properties of the objects, which are to be ranked. Therefore an index is derived to estimate the effect on the ranking, when the set of characteristic properties of objects is enlarged or diminished.With environmental databases as objects, the newly introduced index is exemplified.