Uncertain inference was first described by C. J. van Rijsbergen[1] as a way to formally define a query and document relationship in Information retrieval.
A knowledge base of facts and rules is needed, but some of them may be uncertain because there may be a probability associated to using them for inference.
By doing this it accomplishes two things: Multimedia documents, like images or videos, have different inference properties for each datatype.
The framework of plausible inference allows us to measure and combine the probabilities coming from these different properties.
Uncertain inference generalizes the notions of autoepistemic logic, where truth values are either known or unknown, and when known, they are true or false.
In office documents the independence assumption is valid since the query will focus on their individual attributes.
Besides analysing the content of documents one can also query about the author, size, topic or collection for example.