A representation of complex events and processes for the acquisition of knowledge from texts

Abstract

Temporal event hierarchies are proposed as a technique to represent knowledge in texts describing processes. The representation is that which a program, without prior knowledge about these processes, will be able to acquire by reading a description of a process. The representation is intended to be used by programs that acquire knowledge from texts. This representation is viewed as a bridge between the English description of a biological system and deeper representations of systems such as those proposed by qualitative physics and model-based reasoning. The representation is based on temporal relationships that are used to index and organize knowledge about biological systems (circulatory, respiratory, urinary, etc.) in a hierarchy of events. Several reasoning methods that the proposed representation permits are explained. The event centered representation proposed here is also related to object centered representations. Finally, algorithms for the automated construction of the event hierarchies are explained.