Grammar induction from (lots of) words alone
Grammar induction is the task of learning syntactic structure in a setting where that structure is hidden. Grammar induction from words alone is interesting because it is similiar to the problem that a child learning a language faces. Previous work has typically assumed richer but cognitively implausible input, such as POS tag annotated data, which makes that work less relevant to human language acquisition. We show that grammar induction from words alone is in fact feasible when the model is provided with sufficient training data, and present two new streaming or mini-batch algorithms for PCFG inference that can learn from millions of words of training data. We compare the performance of these algorithms to a batch algorithm that learns from less data. The minibatch algorithms outperform the batch algorithm, showing that cheap inference with more data is better than intensive inference with less data. Additionally, we show that the harmonic initialiser, which previous work identified as essential when learning from small POS-tag annotated corpora (Klein and Manning, 2004), is not superior to a uniform initialisation.
Code (1)
Tasks
Language AcquisitionPOSTAGTopic ModelsSimilar Papers 제목 키워드 기반
Variance of Average Surprisal: A Better Predictor for Quality of Grammar from Unsupervised PCFG Induction
In unsupervised grammar induction, data likelihood is known to be only weakly correlated with parsing accuracy, especially at convergence after multiple runs. In order to find a better indicator for quality of induced gr…
Model SelectionDependency Induction Through the Lens of Visual Perception
Most previous work on grammar induction focuses on learning phrasal or dependency structure purely from text. However, because the signal provided by text alone is limited, recently introduced visually grounded syntax mo…
Constituency Grammar InductionConstituency ParsingDependency ParsingImproved Combinatory Categorial Grammar Induction with Boundary Words and Bayesian Inference
The Return of Lexical Dependencies: Neural Lexicalized PCFGs
In this paper we demonstrate that $\textit{context free grammar (CFG) based methods for grammar induction benefit from modeling lexical dependencies}$. This contrasts to the most popular current methods for grammar induc…
Grounded PCFG Induction with Images
Recent work in unsupervised parsing has tried to incorporate visual information into learning, but results suggest that these models need linguistic bias to compete against models that only rely on text. This work propos…
Prepositional Phrase Attachment