Researcher

Alexander Clark

Alexander Clark develops algorithms for learning language structure from text, linking formal grammar with unsupervised machine learning. He earned degrees at Cambridge and Sussex, then published methods for syntax and grammar induction. His career includes a 2010 Best Paper Award at CoNLL, research on the computational complexity of language acquisition, and the coauthored book Empiricism and Language Learnability. As of October 2026, he is a Visiting Research Fellow at the University of Gothenburg, where he presents work on syntactic learning beyond context-free grammars.

Works
74
Citations
1,345
h-index
18

Publication numbers from OpenAlex, as of 18 October 2026.

Timeline

  1. 1986–2002

    Cambridge degrees and a thesis

    He earns a BA from Cambridge in 1986, an MSc from Sussex in 1998, and a PhD in 2001. His 2002 thesis presents statistical algorithms for unsupervised machine learning of natural language.

  2. 2004

    Grammar inference and acquisition

    In 2004, he formalizes first-language acquisition as a problem for statistical learning theory and grammatical inference.

  3. 2010

    A CoNLL paper award

    He receives the Best Paper Award at the Conference on Computational Natural Language Learning in 2010. In a 2010 conference paper, he introduces Distributional Lattice Grammars and an algorithm for learning natural-language syntax.

  4. 2012–2013

    Two language-learning papers

    In 2012, with Ryo Yoshinaka, he extends distributional learning to parallel multiple context-free grammars that can copy constituents recursively. In 2013, with Shalom Lappin, he argues that a central challenge in language acquisition is the computational complexity of constructing a hypothesis from input data.

  5. By 2015

    Lecturer at King's

    By 2015, he is a Lecturer in Logic and Linguistics at King's College London after several years teaching in Royal Holloway's Computer Science department. His career also includes postdoctoral research at the University of Geneva.

  6. 2020

    Learning probabilistic grammars

    With Nathanaël Fijalkow, he presents a distributional-learning algorithm that consistently estimates a large class of probabilistic context-free grammars from strings in 2020.

  7. 2026

    Learnability beyond context-free grammars

    At the 2026 CLASP conference, he presents work on learning syntactic structures beyond context-free grammars. By 2026, his most recent book is Empiricism and Language Learnability, coauthored with Nick Chater, John Goldsmith, and Andy Perfors.

  8. As of October 2026

    Visiting Research Fellow

    He is a Visiting Research Fellow in CLASP, the Centre for linguistic theory and studies in probability, at the University of Gothenburg.

Career

  1. NowUniversity of GothenburgVisiting Research Fellow
  2. 2013–2022King's College LondonLecturer in Logic and Linguistics
  3. 2006–2012University of London
  4. 2005–2012Royal Holloway University of London
  5. 2001–2005University of GenevaPostdoctoral researcher
  6. 2000–2001University of Sussex

Education

  1. 1998University of SussexMSc
  2. 1986University of CambridgeBA

Most-cited works

  1. Unsupervised induction of stochastic context-free grammars using distributional clustering2001 · 149 citations
  2. A Polynomial Algorithm for the Inference of Context Free Languages2008 · Lecture notes in computer science · 140 citations
  3. Inducing syntactic categories by context distribution clustering2000 · 138 citations
  4. Learning auxiliary fronting with grammatical inference2006 · 57 citations
  5. Distributional Learning of Some Context-Free Languages with a Minimally Adequate Teacher2010 · Lecture notes in computer science · 50 citations

Sources and credits

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  1. Alexander Clark - King's College London kclpure.kcl.ac.uk. Checked 18 October 2026.
  2. [cs/0212024] Unsupervised Language Acquisition: Theory and Practice arxiv.org. Checked 18 October 2026.
  3. Grammatical Inference and First Language Acquisition - ACL Anthology aclanthology.org. Checked 18 October 2026.
  4. Grammatical Inference and First Language Acquisition - King's College London kclpure.kcl.ac.uk. Checked 18 October 2026.
  5. Efficient, Correct, Unsupervised Learning of Context-Sensitive Languages - King's College London kclpure.kcl.ac.uk. Checked 18 October 2026.
  6. Beyond Semilinearity: Distributional Learning of Parallel Multiple Context-free Grammars - King's College London kclpure.kcl.ac.uk. Checked 18 October 2026.
  7. Complexity in Language Acquisition - King's College London kclpure.kcl.ac.uk. Checked 18 October 2026.
  8. Alexander Clark | The Linguistic Summer Institute 2015 lsa2015.uchicago.edu. Checked 18 October 2026.
  9. CLASP - Keynotes gu-clasp.github.io. Checked 18 October 2026.
  10. Consistent Unsupervised Estimators for Anchored PCFGs - ACL Anthology aclanthology.org. Checked 18 October 2026.