PhD defence Konstantinos Kogkalidis: How grammatical composition can be more flexible and efficient

On 9 June, Konstantinos Kogkalidis will defend his PhD thesis Dependency as Modality, Parsing as Permutation, in which he seeks a more flexible and efficient grammatical composition.

Dependency as modality

In this thesis, Kogkalidis explores a type-theoretic approach to understanding language, bridging the fields of linguistics, formal logics, and computer science. Specifically, he proposes a novel type calculus of grammatical composition that is more flexible and efficient than traditional approaches.

Kogkalidis’ approach takes an operational shortcut to sentential semantics that engages only minimally with surface syntax. The resulting type calculus produces mixed unary/n-ary trees that directly subsume non-projective labeled dependency trees.

Parsing as permutation

To investigate the formalism’s expressive adequacy, an extraction algorithm is designed and employed to convert syntactic analyses of Dutch sentences into proofs of the target logic.

The resulting proofbank and type lexicon serve as training data for a neurosymbolic proof search system that efficiently navigates the logic’s expansive theorem space. This system consists of a supertagger, a neural permutation module, and the type system itself, and shows superior efficiency and performance compared to established baselines across categorial formalisms.