ABSTRACT
Spatial objects have a geometric and an attribute description. Both can be uncertain because of fuzzy attribute distribution of complex objects or loss of enough cognitive knowledge. As for area object, such as soil class distribution, from a different analytical viewpoint we can say that one determinate attribute has an indeterminate spatial distribution (the distribution boundary is indefinite), or within a determinate polygon the attribute distribution is uncertain with a blend of multi-feature classes. If a soil of type x is mapped as being at a particular location, it is far from certain that an investigator sampling that location would actually find soil type x. Instead soil y might be found, and added as an inclusion in the area mapped as x (Fisher, 1993).
