---
title: "Joint Determination of Anaphoricity and — Denis 2007"
description: "Pairwise coreference systems only decide anaphoricity implicitly."
authors: ["Pascal Denis", "Jason Baldridge"]
year: 2007
venue: "Human Language Technologies 2007: The Conference of the North American Chapter of the Association for Computational Linguistics; Proceedings of the Main Conference"
source: "https://aclanthology.org/N07-1030/"
licence: "CC BY-NC-SA 3.0 (ACL Anthology, before 2016)"
licence_url: "https://creativecommons.org/licenses/by-nc-sa/3.0/"
summary_licence: "Elamur Cosmic License"
canonical: "https://research.elamur.ai/free/papers/denis-2007-joint-determination-anaphoricity-coreference-resolution/"
---
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# Joint Determination of Anaphoricity and Coreference Resolution using Integer Programming

**Authors:** [Pascal Denis](https://md.research.elamur.ai/free/authors/pascal-denis/), [Jason Baldridge](https://md.research.elamur.ai/free/authors/jason-baldridge/) · **Year:** 2007 · **Venue:** Human Language Technologies 2007: The Conference of the North American Chapter of the Association for Computational Linguistics; Proceedings of the Main Conference · **Licence:** [CC BY-NC-SA 3.0 (ACL Anthology, before 2016)](https://creativecommons.org/licenses/by-nc-sa/3.0/)

**Links:** [Publisher's page](https://aclanthology.org/N07-1030/) · [PDF](https://aclanthology.org/N07-1030.pdf) · [OpenAlex](https://openalex.org/W2130031580)

**Citations:** 151 citations (openalex-snapshot · 2026-10-14) · [73](#cited-by) in our library, of the 140673 papers whose bibliographies we read

## Summary
Pairwise coreference systems only decide anaphoricity implicitly. As a result, they may link non-anaphoric mentions to antecedents or leave genuine anaphors unresolved. Earlier fixes placed a separate anaphoricity classifier in front of the coreference model as a filter, but such cascades depend on a carefully tuned threshold. Denis and Baldridge instead treat coreference as an integer linear programming (ILP) problem. Two maximum entropy classifiers, one scoring mention pairs and one scoring whether a mention is anaphoric, supply probabilities that serve as weights in the ILP objective. Linear constraints then force the two sets of decisions to be consistent. The authors first build a coreference-only ILP (COREF-ILP) and then the joint model (JOINT-ILP). They test on the three genres of ACE Phase 2 (BNEWS, NPAPER, NWIRE), using true ACE mentions and the Vilain et al. (1995) metric. The joint model improves f-score by 3.7–5.3% over the pairwise baseline, and all differences are significant. The result matters because global inference can combine independently trained local models quickly and without threshold tuning.

## Key points
- Base models are maximum entropy classifiers trained with TADM (Gaussian prior, variance 1000). Training pairs follow Soon et al. (2001), and preprocessing uses the OpenNLP Toolkit.
- Baseline f-scores for COREF-PAIRWISE are 63.9 on BNEWS, 67.6 on NPAPER and 63.8 on NWIRE. The filter cascade (AC-CASCADE) scores lower on BNEWS and NPAPER and only marginally higher on NWIRE.
- The anaphoricity classifier reaches about 80.2% average accuracy. Even with perfect linkage (ORACLE-LINK), its errors cap a cascade at roughly 80–83 f-score.
- JOINT-ILP yields f-score gains of 5.3%, 4.9% and 3.7% across the three ACE datasets, with significance tested by paired t-tests (p \< .05).
- Planned future work includes transitivity constraints, partition-level constraints and linguistic constraints such as pronoun restrictions.

*Our summary of the paper, in our own words — not its text. The work belongs to its authors; read it at the links above.*

Fields: [Linguistics & languages](https://md.research.elamur.ai/free/shelves/linguistics/)

Topics: [Coreference resolution](https://md.research.elamur.ai/free/topics/coreference-resolution/)

## Cited by

Cited by

73 papers of our library cite it (of the 140673 whose bibliographies we read); 41 of them have a page here, 32 not yet.

- [Understanding the Value of Features for Coreference Resolution](https://md.research.elamur.ai/free/papers/bengtson-2008-understanding-value-features-coreference-resolution/)
- [Evaluation Metrics For End-to-End Coreference Resolution Systems](https://md.research.elamur.ai/free/papers/cai-2010-evaluation-metrics-end-end-coreference/)
- [A Constrained Latent Variable Model for Coreference Resolution](https://md.research.elamur.ai/free/papers/chang-2013-constrained-latent-variable-model-coreference/)
- [Improving Event Coreference Resolution by Modeling Correlations between Event Coreference Chains and Document Topic Structures](https://md.research.elamur.ai/free/papers/choubey-2018-improving-event-coreference-resolution-modeling/)
- [Entity-Centric Coreference Resolution with Model Stacking](https://md.research.elamur.ai/free/papers/clark-2015-entity-centric-coreference-resolution-model/)
- [Joint Inference and Disambiguation of Implicit Sentiments via Implicature Constraints](https://md.research.elamur.ai/free/papers/deng-2014-joint-inference-disambiguation-implicit-sentiments/)
- [Specialized Models and Ranking for Coreference Resolution](https://md.research.elamur.ai/free/papers/denis-2008-specialized-models-ranking-coreference-resolution/)
- [Decentralized Entity-Level Modeling for Coreference Resolution](https://md.research.elamur.ai/free/papers/durrett-2013-decentralized-entity-level-modeling-coreference/)
- [Latent Trees for Coreference Resolution](https://md.research.elamur.ai/free/papers/fernandes-2014-latent-trees-coreference-resolution/)
- [Enforcing Transitivity in Coreference Resolution](https://md.research.elamur.ai/free/papers/finkel-2008-enforcing-transitivity-coreference-resolution/)
- [Unsupervised Coreference Resolution in a Nonparametric Bayesian Model](https://md.research.elamur.ai/free/papers/haghighi-2007-unsupervised-coreference-resolution-nonparametric-bayesian/)
- [Simple Coreference Resolution with Rich Syntactic and Semantic Features](https://md.research.elamur.ai/free/papers/haghighi-2009-simple-coreference-resolution-rich-syntactic/)
- [NARC – Norwegian Anaphora Resolution Corpus](https://md.research.elamur.ai/free/papers/hlum-2022-narc-norwegian-anaphora-resolution-corpus/)
- [A Cross-Lingual ILP Solution to Zero Anaphora Resolution](https://md.research.elamur.ai/free/papers/iida-2011-cross-lingual-ilp-solution-zero/)
- [Optimization in Coreference Resolution is not Needed: A Nearly-Optimal Algorithm with Intensional Constraints](https://md.research.elamur.ai/free/papers/klenner-2009-optimization-coreference-resolution-is-not/)
- [Dependency-driven Anaphoricity Determination for Coreference Resolution](https://md.research.elamur.ai/free/papers/kong-2010-dependency-driven-anaphoricity-determination-coreference/)
- [Singletons and Coreference Resolution Evaluation](https://md.research.elamur.ai/free/papers/kubler-2011-singletons-coreference-resolution-evaluation/)
- [Joint Entity and Event Coreference Resolution across Documents](https://md.research.elamur.ai/free/papers/lee-2012-joint-entity-event-coreference-resolution/)
- [Deterministic Coreference Resolution Based on Entity-Centric, Precision-Ranked Rules](https://md.research.elamur.ai/free/papers/lee-2013-deterministic-coreference-resolution-based-entity/)
- [Collective Classification for Fine-grained Information Status](https://md.research.elamur.ai/free/papers/markert-2012-collective-classification-fine-grained-information/)
- [Search Space Pruning: A Simple Solution for Better Coreference Resolvers](https://md.research.elamur.ai/free/papers/moosavi-2016-search-space-pruning-simple-solution/)
- [Unsupervised Models for Coreference Resolution](https://md.research.elamur.ai/free/papers/ng-2008-unsupervised-models-coreference-resolution/)
- [Graph-Cut-Based Anaphoricity Determination for Coreference Resolution](https://md.research.elamur.ai/free/papers/ng-2009-graph-cut-based-anaphoricity-determination/)
- [Supervised Noun Phrase Coreference Research: The First Fifteen Years](https://md.research.elamur.ai/free/papers/ng-2010-supervised-noun-phrase-coreference-research/)
- [Scoring Coreference Chains with Split-Antecedent Anaphors](https://md.research.elamur.ai/free/papers/paun-2023-scoring-coreference-chains-split-antecedent/)
- [A Joint Framework for Coreference Resolution and Mention Head Detection](https://md.research.elamur.ai/free/papers/peng-2015-joint-framework-coreference-resolution-mention/)
- [Solving Hard Coreference Problems](https://md.research.elamur.ai/free/papers/peng-2015-solving-hard-coreference-problems/)
- [Integer Linear Programming for Discourse Parsing](https://md.research.elamur.ai/free/papers/perret-2016-integer-linear-programming-discourse-parsing/)
- [Joint Unsupervised Coreference Resolution with Markov Logic](https://md.research.elamur.ai/free/papers/poon-2008-joint-unsupervised-coreference-resolution-markov/)
- [CoNLL-2011 Shared Task: Modeling Unrestricted Coreference in OntoNotes](https://md.research.elamur.ai/free/papers/pradhan-2011-conll-2011-shared-task-modeling/)
- [CoNLL-2012 Shared Task: Modeling Multilingual Unrestricted Coreference in OntoNotes](https://md.research.elamur.ai/free/papers/pradhan-2012-conll-2012-shared-task-modeling/)
- [Supervised Models for Coreference Resolution](https://md.research.elamur.ai/free/papers/rahman-2009-supervised-models-coreference-resolution/)
- [A Global Relaxation Labeling Approach to Coreference Resolution](https://md.research.elamur.ai/free/papers/sapena-2010-global-relaxation-labeling-approach-coreference/)
- [A Constraint-Based Hypergraph Partitioning Approach to Coreference Resolution](https://md.research.elamur.ai/free/papers/sapena-2013-constraint-based-hypergraph-partitioning-approach/)
- [Supervised and Unsupervised Methods in Employing Discourse Relations for Improving Opinion Polarity Classification](https://md.research.elamur.ai/free/papers/somasundaran-2009-supervised-unsupervised-methods-employing-discourse/)
- [The More Antecedents, the Merrier: Resolving Multi-Antecedent Anaphors](https://md.research.elamur.ai/free/papers/vala-2016-more-antecedents-merrier-resolving-multi/)
- [Limited memory incremental coreference resolution](https://md.research.elamur.ai/free/papers/webster-2014-limited-memory-incremental-coreference-resolution/)
- [Learning Anaphoricity and Antecedent Ranking Features for Coreference Resolution](https://md.research.elamur.ai/free/papers/wiseman-2015-learning-anaphoricity-antecedent-ranking-features/)
- [An Entity-Mention Model for Coreference Resolution with Inductive Logic Programming](https://md.research.elamur.ai/free/papers/yang-2008-entity-mention-model-coreference-resolution/)
- [Domain Adaptation for Coreference Resolution: An Adaptive Ensemble Approach](https://md.research.elamur.ai/free/papers/yang-2012-domain-adaptation-coreference-resolution-adaptive/)
- [Neural Coreference Resolution with Deep Biaffine Attention by Joint Mention Detection and Mention Clustering](https://md.research.elamur.ai/free/papers/zhang-2018-neural-coreference-resolution-deep-biaffine/)

## Cite

The paper itself, not this page. BibTeX from the library's record of the work.

```bibtex
@inproceedings{denis2007joint,
  title = {{Joint Determination of Anaphoricity and Coreference Resolution using Integer Programming}},
  author = {Denis, Pascal and Baldridge, Jason},
  booktitle = {Human Language Technologies 2007: The Conference of the North American Chapter of the Association for Computational Linguistics; Proceedings of the Main Conference},
  year = {2007},
  url = {https://aclanthology.org/N07-1030/}
}
```

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