Are All People Married?: Determining Obligatory Attributes in Knowledge Bases.

An attribute is obligatory for a class in a Knowledge Base (KB), if all instances of the class have the attribute in the real world. For example, has­Birth­Date is an obligatory attribute for the class Person, while has ­ Spouse is not. In this paper, we propose a new way to model incompleteness in KBs. From this model, we derive a method to automatically determine obligatory attributes -- using only the data from the KB. Our algorithm can detect such attributes with a precision of up to 90%.