Proof-Theoretic Aspects of Hybrid Type-Logical Grammars

International audienceThis paper explores proof-theoretic aspects of hybrid type-logical grammars, a logic combining Lambek grammars with lambda grammars. We prove some basic properties of the calculus, such as nor-malisation and the subformula property and also present a proof net calculus for hybrid type-logical grammars. In addition to clarifying the logical foundations of hybrid type-logical grammars, the current study opens the way to variants and extensions of the original system, including but not limited to a non-associative version and a multimodal version incorporating structural rules and unary modes

A Timing Analysis of Right Node Raising Identity

The proper analysis of Right Node Raising (RNR), like other cases of non-standard coordination, has deep repercussions for syntactic theory in general, and the notion of constituency in particular. Such structures are typified by a coordinate structure in which some element shared by both coordinates--the pivot--is only realized once, usually in the right periphery of the coordinate structure, even while it may be simultaneously interpreted in a gap internal to each coordinate.  I advocate a hybrid analysis of RNR, motivating it on the basis of a heuristic I call \textit{pivot-gap identity}. I argue that when the pivot is identical to its in-situ representation in both gaps or the rightmost gap, it is derived via rightward movement from the rightmost conjunction to a conjunct-external position, followed by ellipsis in all other conjuncts. When the pivot is unique with respect to its gaps, it is derived by means of unstructured feature sets in each conjunct being cashed out by the later merger of a genuine lexical item external to the conjunction. The resulting theory is capable of capturing the difference in pivot-gap identity conditions and reconstruction possibilities that characterize different RNR variants

Proof-Theoretic Aspects of Hybrid Type-Logical Grammars

International audienceThis paper explores proof-theoretic aspects of hybrid type-logical grammars, a logic combining Lambek grammars with lambda grammars. We prove some basic properties of the calculus, such as nor-malisation and the subformula property and also present a proof net calculus for hybrid type-logical grammars. In addition to clarifying the logical foundations of hybrid type-logical grammars, the current study opens the way to variants and extensions of the original system, including but not limited to a non-associative version and a multimodal version incorporating structural rules and unary modes

Breaking NLP: Using Morphosyntax, Semantics, Pragmatics and World Knowledge to Fool Sentiment Analysis Systems

This paper describes our “breaker” submission to the 2017 EMNLP “Build It Break It” shared task on sentiment analysis. In order to cause the “builder” systems to make incorrect predictions, we edited items in the blind test data according to linguistically interpretable strategies that allow us to assess the ease with which the builder systems learn various components of linguistic structure. On the whole, our submitted pairs break all systems at a high rate (72.6%), indicating that sentiment analysis as an NLP task may still have a lot of ground to cover. Of the breaker strategies that we consider, we find our semantic and pragmatic manipulations to pose the most substantial difficulties for the builder systems

Modeling morphological learning, typology, and change : What can the neural sequence-to-sequence framework contribute?

We survey research using neural sequence-to-sequence models as computational models of morphological learning and learnability. We discuss their use in determining the predictability of inflectional exponents, in making predictions about language acquisition and in modeling language change. Finally, we make some proposals for future work in these areas