A Mention-Ranking Model for Abstract Anaphora Resolution

Resolving abstract anaphora is an important, but difficult task for text understanding. Yet, with recent advances in representation learning this task becomes a more tangible aim. A central property of abstract anaphora is that it establishes a relation between the anaphor embedded in the anaphoric sentence and its (typically non-nominal) antecedent. We propose a mention-ranking model that learns how abstract anaphors relate to their antecedents with an LSTM-Siamese Net. We overcome the lack of training data by generating artificial anaphoric sentence--antecedent pairs. Our model outperforms state-of-the-art results on shell noun resolution. We also report first benchmark results on an abstract anaphora subset of the ARRAU corpus. This corpus presents a greater challenge due to a mixture of nominal and pronominal anaphors and a greater range of confounders. We found model variants that outperform the baselines for nominal anaphors, without training on individual anaphor data, but still lag behind for pronominal anaphors. Our model selects syntactically plausible candidates and -- if disregarding syntax -- discriminates candidates using deeper features.Comment: In Proceedings of the 2017 Conference on Empirical Methods in Natural Language Processing (EMNLP). Copenhagen, Denmar

PERFORMING ANAPHORA IN MODERN GREEK: A NEO-GRICEAN PRAGMATIC ANALYSIS

The paper addresses the problem of interpreting anaphoric NPs in Modern Greek. It includes a proposal of a novel analysis based on the systematic interaction of the neo- Gricean pragmatic principles of communication, which provides a neat and elegant approach to NP-anaphora resolution. The findings of this study provide evidence for an account of NP-anaphora in terms of the division of labour between syntax and pragmatics and more accurately in terms of the systematic interaction of the neo-Gricean pragmatic principles

Focusing for Pronoun Resolution in English Discourse: An Implementation

Anaphora resolution is one of the most active research areas in natural language processing. This study examines focusing as a tool for the resolution of pronouns which are a kind of anaphora. Focusing is a discourse phenomenon like anaphora. Candy Sidner formalized focusing in her 1979 MIT PhD thesis and devised several algorithms to resolve definite anaphora including pronouns. She presented her theory in a computational framework but did not generally implement the algorithms. Her algorithms related to focusing and pronoun resolution are implemented in this thesis. This implementation provides a better comprehension of the theory both from a conceptual and a computational point of view. The resulting program is tested on different discourse segments, and evaluation and analysis of the experiments are presented together with the statistical results.Comment: iii + 49 pages, compressed, uuencoded Postscript file; revised version of the first author's Bilkent M.S. thesis, written under the supervision of the second author; notify Akman via e-mail ([email protected]) or fax (+90-312-266-4126) if you are unable to obtain hardcopy, he'll work out somethin

Vagueness and referential ambiguity in a large-scale annotated corpus

In this paper, we argue that difficulties in the definition of coreference itself contribute to lower inter-annotator agreement in certain cases. Data from a large referentially annotated corpus serves to corroborate this point, using a quantitative investigation to assess which effects or problems are likely to be the most prominent. Several examples where such problems occur are discussed in more detail, and we then propose a generalisation of Poesio, Reyle and Stevenson’s Justified Sloppiness Hypothesis to provide a unified model for these cases of disagreement and argue that a deeper understanding of the phenomena involved allows to tackle problematic cases in a more principled fashion than would be possible using only pre-theoretic intuitions

Non-situational functions of demonstrative noun phrases in Lingala (Bantu)

This paper examines the non-situational (i.e., non-exophoric) pragmatic functions of the three adnominal demonstratives, oyo, wand, and yango in the Bantu language Lingala. An examination of natural language corpora reveals that, although native-speaker intuitions sanction the use of oyo as an anaphor in demonstrative NPs, this demonstrative is hardly ever used in that role. It also reveals that wand, which has both situational and discourse-referential capacities, is used more frequently than the exclusively anaphoric demonstrative yango. It is explained that wand appears in a wide range of non-coreferential expression types, in coreferential expression types involving low-salience referents, and in coreferential expression types that both involve highly salient referents and include the speaker's desire to signal a shift in the mental representation of the referent towards a pejorative reading. The use of yango, on the other hand, is only licensed in cases of coreferentiality involving highly salient referents and implying continuation of the same mental representation of the referent. A specific section is devoted to charting the possible grammaticalization paths followed by the demonstratives. Conclusions are drawn for pragmatic theory formation in terms of the relation between form (yango vs. wand) and function (coreferentiality vs. non-coreferentiality)