Constantine Lignos

Assistant Professor of Linguistics in the Department of Computer Science

Departments/Programs

Computer Science
Volen National Center for Complex Systems

Degrees

University of Pennsylvania, Ph.D.
University of Pennsylvania, M.S.
Yale University, B.A.

Expertise

Computational linguistics, natural language processing, low-resource language technology and resources, language acquisition, and computational psycholinguistics.

Profile

I direct the Broadening Linguistic Technologies Lab at Brandeis University, where I am affiliated with the Computer Science Department, Computational Linguistics Program, and Linguistics Program. The overarching goal of my research is to broaden the depth and breadth of human language technology, with a focus on understudied problems in computational linguistics.

The primary thrust of my current work is eliminating the barriers to useful language technology for every living written language, especially lower-resourced and minoritized languages. I also continue to study the representation of language in the mind, including language acquisition, processing, and change.

I did my graduate work in Computer Science at The University of Pennsylvania (Ph.D. 2013), advised by Mitch Marcus and Charles Yang. I then completed a post-doctoral fellowship at The Children's Hospital of Philadelphia exploring clinical applications of statistical models of language processing. I was a researcher at BBN Technologies and USC Information Sciences Institute. In summer 2019, I joined the computational linguistics faculty at Brandeis University.

More information is available on my website: https://lignos.org/. Webpage

Courses Taught

COSI	114a	Fundamentals of Natural Language Processing I
COSI	216a	Topics in Natural Language Processing
COSI	217b	Natural Language Processing Systems

Scholarship

Thamme Gowda, Weiqiu You, Constantine Lignos, and Jonathan May. "Macro-Average: Rare Types Are Important Too." Proceedings of the 2021 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, Association for Computational Linguistics, 2021. (forthcoming)

David Ifeoluwa Adelani, Jade Abbott, Graham Neubig, Daniel D'souza, Julia Kreutzer, Constantine Lignos, Chester Palen-Michel, Happy Buzaaba, Shruti Rijhwani, Sebastian Ruder, Stephen Mayhew, Israel Abebe Azime, Shamsuddeen Muhammad, and others. "MasakhaNER: Named Entity Recognition for African Languages." Proceedings of the AfricaNLP Workshop at the 16th Conference of the European Chapter of the Association for Computational Linguistics, 2021.

Jingxuan Tu and Constantine Lignos. "TMR: Evaluating NER Recall on Tough Mentions." Proceedings of the Student Research Workshop at the 16th Conference of the European Chapter of the Association for Computational Linguistics, Association for Computational Linguistics, 2021.

Jonne Sälevä and Constantine Lignos. "Mining Wikidata for Name Resources for African Languages." Proceedings of the AfricaNLP Workshop at the 16th Conference of the European Chapter of the Association for Computational Linguistics, 2021.

Jonne Sälevä and Constantine Lignos. "The Effectiveness of Morphology-aware Segmentation in Low-Resource Neural Machine Translation." Proceedings of the Student Research Workshop at the 16th Conference of the European Chapter of the Association for Computational Linguistics, Association for Computational Linguistics, 2021.

Constantine Lignos and Marjan Kamyab. "If You Build Your Own NER Scorer, Non-replicable Results Will Come." Proceedings of the 2020 Workshop on Insights from Negative Results in NLP, Association for Computational Linguistics, November 16-20, 2020.

Molly Moran and Constantine Lignos. "Effective Architectures for Low-resource Named Entity Transliteration." Proceedings of the Low Resource Machine Translation Workshop 2020, Association for Computational Linguistics, 2020.

Constantine Lignos, Chester Palen-Michel, Oskar Singer, Pedro Szekely, and Elizabeth Boschee. "Real-world causal relationship discovery from text." ISWC 2019 Satellite Tracks, Auckland, New Zealand. CEUR Workshop Proceedings, 2019.

Constantine Lignos, Daniel Cohen, Yen-Chieh Lien, Pratik Mehta, W. Bruce Croft, and Scott Miller. "The challenges of optimizing machine translation for low resource cross-language information retrieval." 2019 Conference on Empirical Methods in Natural Language Processing, Hong Kong, China. Association for Computational Linguistics, 2019.

Elizabeth Boschee, Joel Barry, Jayadev Billa, Marjorie Freedman, Thamme Gowda, Constantine Lignos, Chester Palen-Michel, Michael Pust, Banrishkhem K. Klonglah, Srikanth Madikeri, Jonahan May, Scott Miller. "SARAL: A low-resource cross-lingual domain-focused information retrieval system for effective rapid document triage." ACL 2019, Florence, Italy. Association for Computational Linguistics, 2019.