Measuring Thematic Fit with Distributional Feature Overlap

In this paper, we introduce a new distributional method for modeling predicate-argument thematic fit judgments. We use a syntax-based DSM to build a prototypical representation of verb-specific roles: for every verb, we extract the most salient second order contexts for each of its roles (i.e. the most salient dimensions of typical role fillers), and then we compute thematic fit as a weighted overlap between the top features of candidate fillers and role prototypes. Our experiments show that our method consistently outperforms a baseline re-implementing a state-of-the-art system, and achieves better or comparable results to those reported in the literature for the other unsupervised systems. Moreover, it provides an explicit representation of the features characterizing verb-specific semantic roles.Comment: 9 pages, 2 figures, 5 tables, EMNLP, 2017, thematic fit, selectional preference, semantic role, DSMs, Distributional Semantic Models, Vector Space Models, VSMs, cosine, APSyn, similarity, prototyp

From the choice of the patients for a transitive verb to its polysemy

Nous faisons l’hypothèse qu’un verbe de procès renvoie à la représentation d’une situation. Nous examinons cette hypothèse dans le cadre de la polysémie verbale pour 12 verbes du français. Deux tâches sont mises en place : une tâche de production de synonymes (tâche 1) et une tâche de production de patients (tâche 2). La tâche 1 met en évidence deux interprétations pour chacun des verbes, l’une dominante et l’autre secondaire. La tâche 2 conduit à observer une forte corrélation entre la dominance relative de la signification et le nombre de patients produits.Les résultats sont compatibles avec l’hypothèse que des liens existent en mémoire permanente entre un verbe et ses rôles thématiques, et que les modélisations de la mémoire doivent les prendre en compte. Ils permettent également de supposer qu’une production implicite d’argument se met en place rapidement lorsque le verbe est présenté seul.We hypothesized that a process verb refers to the representation of a situation. We examined this hypothesis within the framework of verb polysemy for 12 French verbs. Two tasks were used: a synonym production task (task 1) and a patient production task (task 2). Task 1 revealed two interpretations for each of the verbs, one dominant and the other secondary. Task 2 indicated a high level of correlation between the relative dominance of an interpretation and the number of patients produced. The results are compatible with the hypothesis that memory contains permanent links between a verb and its thematic roles and that memory models must take account of these. They also suggest that the implicit production of an argument occurs rapidly when the verb is presented on its own

The VERBMOBIL domain model version 1.0

This report describes the domain model used in the German Machine Translation project VERBMOBIL. In order make the design principles underlying the modeling explicit, we begin with a brief sketch of the VERBMOBIL demonstrator architecture from the perspective of the domain model. We then present some rather general considerations on the nature of domain modeling and its relationship to semantics. We claim that the semantic information contained in the model mainly serves two tasks. For one thing, it provides the basis for a conceptual transfer from German to English; on the other hand, it provides information needed for disambiguation. We argue that these tasks pose different requirements, and that domain modeling in general is highly task-dependent. A brief overview of domain models or ontologies used in existing NLP systems confirms this position. We finally describe the different parts of the domain model, explain our design decisions, and present examples of how the information contained in the model can be actually used in the VERBMOBIL demonstrator. In doing so, we also point out the main functionality of FLEX, the Description Logic system used for the modeling

Teasing apart Syntactic Category vs. Argument Structure Information in Deverbal Word Formation: a comparative psycholinguistic study.

Deverbal word formation is subject to two distinct types of constraints, those concerning the syntactic category of the base (categorial constraints) and those relating to the thematic properties of the verb (thematic constraints). For instance, -able suffixation involves a transitive verb with argument structure >, as in to train > trainable. Violation of these constraints results in the creation of pseudo-words with categorial (e.g. riverable) or thematic violations (e.g. arrivable). The study discusses psycholinguistic experiments involving these types of deverbal pseudo-words, in Greek and English, two languages with morphologically distinct properties. Greek has a rich derivational system with a variety of deverbal formations, which follow strong constraints, in the sense that most suffixes that participate in deverbal word formation lack the polysemy that allows them to attach to other-than-verbal bases. English, on the other hand, demonstrates an equally rich derivational system, but it differs in two crucial ways: (a) there is significant affix homophony (e.g. -er is a nominalizer if attached to verbal stems, or forms the comparative if attached to adjectives), (b) it is extremely permissive in allowing zero-derived verbs (to fax). In an off-line and two on-line lexical decision tasks we investigated whether categorial and thematic constraints are treated in the same way by speakers of both languages. Results showed that speakers of both languages differentiated between pseudo-words that violate these two types of constraints both when it comes to acceptance rates and processing time. Taking together results from both languages, we make claims about the structured mental representation of deverbal derivatives and the fact that their various properties can be accessed via distinct operations and at distinct points of time. Implications for the psycholinguistic theory of lexical access and the morphological theory of word formation are also discussed

A distributional investigation of German verbs

Diese Dissertation bietet eine empirische Untersuchung deutscher Verben auf der Grundlage statistischer Beschreibungen, die aus einem großen deutschen Textkorpus gewonnen wurden. In einem kurzen Überblick über linguistische Theorien zur lexikalischen Semantik von Verben skizziere ich die Idee, dass die Verbbedeutung wesentlich von seiner Argumentstruktur (der Anzahl und Art der Argumente, die zusammen mit dem Verb auftreten) und seiner Aspektstruktur (Eigenschaften, die den zeitlichen Ablauf des vom Verb denotierten Ereignisses bestimmen) abhängt. Anschließend erstelle ich statistische Beschreibungen von Verben, die auf diesen beiden unterschiedlichen Bedeutungsfacetten basieren. Insbesondere untersuche ich verbale Subkategorisierung, Selektionspräferenzen und Aspekt. Alle diese Modellierungsstrategien werden anhand einer gemeinsamen Aufgabe, der Verbklassifikation, bewertet. Ich zeige, dass im Rahmen von maschinellem Lernen erworbene Merkmale, die verbale lexikalische Aspekte erfassen, für eine Anwendung von Vorteil sind, die Argumentstrukturen betrifft, nämlich semantische Rollenkennzeichnung. Darüber hinaus zeige ich, dass Merkmale, die die verbale Argumentstruktur erfassen, bei der Aufgabe, ein Verb nach seiner Aspektklasse zu klassifizieren, gut funktionieren. Diese Ergebnisse bestätigen, dass diese beiden Facetten der Verbbedeutung auf grundsätzliche Weise zusammenhängen.This dissertation provides an empirical investigation of German verbs conducted on the basis of statistical descriptions acquired from a large corpus of German text. In a brief overview of the linguistic theory pertaining to the lexical semantics of verbs, I outline the idea that verb meaning is composed of argument structure (the number and types of arguments that co-occur with a verb) and aspectual structure (properties describing the temporal progression of an event referenced by the verb). I then produce statistical descriptions of verbs according to these two distinct facets of meaning: In particular, I examine verbal subcategorisation, selectional preferences, and aspectual type. All three of these modelling strategies are evaluated on a common task, automatic verb classification. I demonstrate that automatically acquired features capturing verbal lexical aspect are beneficial for an application that concerns argument structure, namely semantic role labelling. Furthermore, I demonstrate that features capturing verbal argument structure perform well on the task of classifying a verb for its aspectual type. These findings suggest that these two facets of verb meaning are related in an underlying way

An Exploration of Semantic Features in an Unsupervised Thematic Fit Evaluation Framework

Thematic fit is the extent to which an entity fits a thematic role in the semantic frame of an event, e.g., how well humans would rate “knife” as an instrument of an event of cutting. We explore the use of the SENNA semantic role-labeller in defining a distributional space in order to build an unsupervised model of event-entity thematic fit judgements. We test a number of ways of extracting features from SENNA-labelled versions of the ukWaC and BNC corpora and identify tradeoffs. Some of our Distributional Memory models outperform an existing syntax-based model (TypeDM) that uses hand-crafted rules for role inference on a previously tested data set. We combine the results of a selected SENNA-based model with TypeDM’s results and find that there is some amount of complementarity in what a syntactic and a semantic model will cover. In the process, we create a broad-coverage semantically-labelled corpus

Argument structure, conceptual metaphor and semantic change : how to succeed in Indo-European without really trying

In contrast to grammaticalization studies of lexical verbs changing into auxiliaries, the realm of semantic changes associated with lexical verbs is an understudied area of historical semantics. We concentrate on the emergence of verbs of success from more semantically concrete verbs, uncovering six conceptual metaphors which all co-occur with non-canonical encoding of subjects in Indo-European. Careful scrutiny of the relevant data reveals a semantic development most certainly inherited from Indo-European; hence, we reconstruct a DAT-‘succeeds’ construction at different levels of schematicity for Proto-Indo-European, including a novel reconstruction of a conceptual metaphor, success is motion forward, and the mapping between this metaphor and the verb-class-specific argument structure construction. Hence, this article offers a systematic analysis of regularity in semantic change, highlighting the importance of predicate and argument structure for lexical semantic developments

Differential processing effects within second group Modern Greek verbs

International audienceOn-line processing of Greek 2nd group verbs was examined through a psycholinguistic experiment using the masked priming technique. The critical comparison concerned the effect of past tense primes on present tense targets between the two forms of the same verb: 2nd group basic verbs and their alternative forms. Results showed that alternative forms elicit morphological priming whereas basic forms do not, and this cannot be compatible with a decompositional approach. We propose an interpretation based on a lexematic approach within an interactive activation model (IAM, McClelland & Rumelhart, 1981). In the discussion, we underline the difficulty in avoiding methodological caveats when transferring logic and material constitution techniques (mostly based on orthographic-phonological criteria) directly from one language to another. The experiment presented here highlights the need to consider a given verbal system in its complexity when designing a psycholinguistic experiment