Anaphor

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An anaphor is a word that in an anaphora relation with an anaphor antecedent.



References

2016

  • (Wikipedia, 2016) ⇒ http://wikipedia.org/wiki/Anaphora_(linguistics) Retrieved:2016-3-28.
    • In linguistics, anaphora () is the use of an expression the interpretation of which depends upon another expression in context (its antecedent or postcedent). In a narrower sense, anaphora is the use of an expression which depends specifically upon an antecedent expression, and thus is contrasted with cataphora, which is the use of an expression which depends upon a postcedent expression. The anaphoric (referring) term is called an anaphor. For example, in the sentence Sally arrived, but nobody saw her, the pronoun her is an anaphor, referring back to the antecedent Sally. In the sentence Before her arrival, nobody saw Sally, the pronoun her refers forward to the postcedent Sally, so her is now a cataphor (and an anaphor in the broader, but not the narrower, sense). Usually, an anaphoric expression is a proform or some other kind of deictic (contextually-dependent) expression. [1] Both anaphora and cataphora are species of endophora, referring to something mentioned elsewhere in a dialog or text. Anaphora is an important concept for different reasons and on different levels: first, anaphora indicates how discourse is constructed and maintained; second, anaphora binds different syntactical elements together at the level of the sentence; third, anaphora presents a challenge to natural language processing in computational linguistics, since the identification of the reference can be difficult; and fourth, anaphora tells some things about how language is understood and processed, which is relevant to fields of linguistics interested in cognitive psychology. [2]
  1. Tognini-Bonelli (2001:70) writes that "an anaphor is a linguistic entity which indicates a referential tie to some other linguistic entity in the same text".
  2. The four ways just listed in which anaphora is important for linguistics are from McEnery (2000:3).

2009

  • WordNet
    • a word (such as a pronoun) used to avoid repetition; the referent of an anaphor is determined by its antecedent
  • (Wikipedia, 2009) ⇒ http://en.wikipedia.org/wiki/Antecedent_(grammar)
    • In grammar, an antecedent is generally the noun or noun phrase to which an anaphor refers in a coreference. However, an antecedent can also be a clause, especially when the anaphor is a demonstrative. ...
  • http://www.m-w.com/dictionary/anaphoric
    • "anaphor: being a word or phrase that takes its reference from another word or phrase and especially from a preceding word or phrase."
  • http://www.m-w.com/dictionary/cataphoric
    • "cataphor: being a word or phrase (as a pronoun) that takes its reference from a following word or phrase (as her in 'Before her Jane saw nothing but desert')"
  • http://www.m-w.com/dictionary/pronoun
    • "pronoun: any of a small set of words in a language that are used as substitutes for nouns or noun phrases and whose referents are named or understood in the context." Can be of type: personal, possessive, reciprocal or reflexive.

1999

  • (Mitkov, 1999) ⇒ Ruslan Mitkov. (1999). “Anaphora Resolution: The State of the Art." Technical report. University of Wolverhampton.
    • The etymology of the term "anaphora" goes back to Ancient Greek with “anaphora” (anajora) being a compound word consisting of the separate words ana - back, upstream, back in an upward direction and jora - the act of carrying and denoted the act of carrying back upstream. For Computational Linguists embarking upon research in the field of anaphor resolution, I strongly recommend as a primer Graham Hirst's book "Anaphora in natural language understanding" (Hirst 1981) which may seem a bit dated in that it does not include developments in the 80's and the 90's, but which provides an excellent survey of the theoretical work on anaphora and of the early computational approaches and is still very useful reading.
    • Various definitions of anaphora have been put forward, but I am tempted to paraphrase the classical definition given by Halliday and Hasan (Halliday & Hasan 1976) which is based on the notion of cohesion: anaphora is cohesion (presupposition) which points back to some previous item. [1 We shall not discuss cataphora which is the case when the "anaphor" precedes the antecedent. For example "Because she was going to the post office, Julie was asked to post a small parcel"] expressions and having the same referent in the real world, they are termed coreferential. [2 The relation between the anaphor and the antecedent is not to be confused with that between the anaphor and its referent; in the example below the referent is "the Empress" as a person in the real word whereas the antecedent is "the Empress" as a linguistic form.] The "pointing back" (reference) is called an anaphor and the entity to which it refers is its antecedent. The process of determining the antecedent of an anaphor is called anaphora resolution. Usually, both the antecedent and the anaphor are used as referring.
      Example (Huddleston 1984). “The Empress hasn't arrived yet but she should be here any minute."

      In this example, the pronoun "she" is the anaphor (for classification of anaphors, see below) and "the Empress" is the antecedent. Please note that the antecedent is not the noun "Empress" but the noun phrase "the Empress".

      There may be cases when the anaphor and more than one of the preceding (or following) entities (usually noun phrases) have the same referent and are therefore pairwise coreferential, thus forming a coreferential chain. In such a case, we regard each of the preceding entities which are coreferential with the anaphor(s) as a legitimate antecedent. Therefore, in such cases the task of anaphora resolution is considered successful, if any of the preceding entities in the coreferential chain is identified as an antecedent. Our paper will discuss the task of anaphora resolution only and not coreference resolution (except for briefly mentioning it in section 4.2). For more on coreference resolution, I suggest the reader consult the MUC (Message Understating Conference) Proceedings in which coreference resolution is extensively covered.

      There are various types of anaphora (Hirst 1981), but we will shall briefly outline those that are thought to be the three most widespread types in the Computational Linguistics literature.

    • Pronomial Anaphora
    • Definite noun phrase anaphora
      • Typical cases of definite noun phrase anaphora is when the antecedent is referred by a definite noun phrase representing either same concept (repetition) or semantically close concepts (e.g. synonyms, superordinates).
        Example: Computational Linguists from many different countries attended the tutorial. The participants found it hard to cope with the speed of the presentation.
    • One-anaphora
      • One-anaphora is the case when the anaphoric expression is realised by a "one" noun phrase. Example: If you cannot attend a tutorial in the morning, you can go for an afternoon one.
    • Finally, we distinguish intrasentential anaphors (referring to an antecedent which is in the same sentence as the anaphor) and intersentential anaphors (referring to an antecedent which is in a different sentence from that of the anaphor).