Temporal annotation
Temporal annotation is the study of how to automatically add semantic information regarding time to natural language documents. It plays a role in natural language processing and computational linguistics.
About
Temporal annotation involves the application of a semantic annotation to a document. Significant temporal annotation standards include TimeML, ISO-TimeML and TIDES. These standards typically include annotations for some or all of temporal expressions, events, temporal relations, temporal signals, and temporal relation types.In natural language texts, events may be associated with times; e.g., they may start or end at a given at a time. Events are also associated with other events, like occurring before or after them. We call these relations temporal relations. Temporal relation typing classifies the relation between two arguments, and is an important and difficult sub-task of figuring out all the temporal information in a document. Allen's interval algebra is one scheme for types of temporal relations. Rule-engineering and machine learning approaches to temporal annotation have both been successful, though achieving high performance in temporal relation typing remains a difficult task.