Temporal annotation is the study of how to automatically add semantic information regarding

time Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, to ...

natural language In neuropsychology, linguistics, and philosophy of language, a natural language or ordinary language is any language that has evolved naturally in humans through use and repetition without conscious planning or premeditation. Natural languages ...

documents. It plays a role in

natural language processing Natural language processing (NLP) is an interdisciplinary subfield of linguistics, computer science, and artificial intelligence concerned with the interactions between computers and human language, in particular how to program computers to pro ...

and

computational linguistics Computational linguistics is an Interdisciplinarity, interdisciplinary field concerned with the computational modelling of natural language, as well as the study of appropriate computational approaches to linguistic questions. In general, comput ...

About

Temporal annotation involves the application of a semantic annotation to a document. Significant temporal annotation standards include

TimeML TimeML is a set of rules for encoding documents electronically. It is defined in the TimeML Specification version 1.2.1 developed by several efforts, led in large part by the Laboratory for Linguistics and Computation at Brandeis University. Th ...

ISO-TimeML ISO 24617-1:2009, ISO-TimeML is the International Organization for Standardization ISO/TC37 standard for time and event markup and annotation. The scope is standardization of principles and methods relating to the annotation of temporal events in ...

and

TIDES Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide tables can ...

. These standards typically include annotations for some or all of temporal expressions (or ''timexes''), 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 ''For the type of boolean algebra called interval algebra, see Boolean algebra (structure)'' Allen's interval algebra is a calculus for temporal reasoning that was introduced by James F. Allen in 1983. The calculus defines possible relations b ...

is one scheme for types of temporal relations. Rule-engineering and

machine learning Machine learning (ML) is a field of inquiry devoted to understanding and building methods that 'learn', that is, methods that leverage data to improve performance on some set of tasks. It is seen as a part of artificial intelligence. Machine ...

approaches to temporal annotation have both been successful, though achieving high performance in temporal relation typing remains a difficult task.

Applications

Successful temporal annotation enables systems to find out when facts asserted in texts are true, to build timelines, to extract plans, and to discover mentions of change. This has had applications in many domains, such as

information extraction Information extraction (IE) is the task of automatically extracting structured information from unstructured and/or semi-structured machine-readable documents and other electronically represented sources. In most of the cases this activity concer ...

digital history Digital history is the use of digital media to further historical analysis, presentation, and research. It is a branch of the digital humanities and an extension of quantitative history, cliometrics, and computing. Digital history is commonly d ...

, processing

social media Social media are interactive media technologies that facilitate the creation and sharing of information, ideas, interests, and other forms of expression through virtual communities and networks. While challenges to the definition of ''social medi ...

, and clinical

text mining Text mining, also referred to as ''text data mining'', similar to text analytics, is the process of deriving high-quality information from text. It involves "the discovery by computer of new, previously unknown information, by automatically extract ...

Evaluation

The TempEval task series sets a shared temporal annotation task, and has run at

SemEval SemEval (Semantic Evaluation) is an ongoing series of evaluations of computational semantic analysis systems; it evolved from the Senseval word sense evaluation series. The evaluations are intended to explore the nature of meaning in language. ...

three times, attracting system entries from around the world. The task originally centred on determining the types of temporal relations only. In TempEval-2 and -3, this expanded to include event and timex annotation. In addition, the

i2b2 I, or i, is the ninth letter and the third vowel letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''i'' (pronounced ), plural ...

clinical evaluation shared task was a temporal annotation exercise in 2012, which attracted a great deal of interest.

References

{{reflist

External links

TimeML.orgTHYME projectPheme project
Computational linguistics Natural language processing Semantics Lexical semantics

About

Applications

Evaluation

See also

Further reading

References

External links