In a large-scale distributed environment of autonomous agents,
information can no longer be expressed concisely, as expected by database
and semantic web technologies, but have to deal with numerous sources of uncertainty.
Current reasoning techniques for handling uncertainty have typically been developed for isolated problems.
The ES approach needs a common abstraction framework for reasoning under uncertainty, handling
complex conditional relationships between various sources of uncertainty and their models.
Trustworthiness
Semantic Web style metadata sources have non-uniform uncertainty and this cause different problem in managing such an information.
A possible solution is to manage it through a modal possibilistic reasoning based on
trust assertions. A detailed discussion here
