165 research outputs found

    GermEval 2014 Named Entity Recognition Shared Task: Companion Paper

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    This paper describes the GermEval 2014 Named Entity Recognition (NER) Shared Task workshop at KONVENS. It provides background information on the motivation of this task, the data-set, the evaluation method, and an overview of the participating systems, followed by a discussion of their results. In contrast to previous NER tasks, the GermEval 2014 edition uses an extended tagset to account for derivatives of names and tokens that contain name parts. Further, nested named entities had to be predicted, i.e. names that contain other names. The eleven participating teams employed a wide range of techniques in their systems. The most successful systems used state-of-the- art machine learning methods, combined with some knowledge-based features in hybrid systems

    GermEval 2014 Named Entity Recognition Shared Task: Companion Paper

    Get PDF
    This paper describes the GermEval 2014 Named Entity Recognition (NER) Shared Task workshop at KONVENS. It provides background information on the motivation of this task, the data-set, the evaluation method, and an overview of the participating systems, followed by a discussion of their results. In contrast to previous NER tasks, the GermEval 2014 edition uses an extended tagset to account for derivatives of names and tokens that contain name parts. Further, nested named entities had to be predicted, i.e. names that contain other names. The eleven participating teams employed a wide range of techniques in their systems. The most successful systems used state-of-the- art machine learning methods, combined with some knowledge-based features in hybrid systems

    Investigating semantic subspaces of Transformer sentence embeddings through linear structural probing

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    The question of what kinds of linguistic information are encoded in different layers of Transformer-based language models is of considerable interest for the NLP community. Existing work, however, has overwhelmingly focused on word-level representations and encoder-only language models with the masked-token training objective. In this paper, we present experiments with semantic structural probing, a method for studying sentence-level representations via finding a subspace of the embedding space that provides suitable task-specific pairwise distances between data-points. We apply our method to language models from different families (encoder-only, decoder-only, encoder-decoder) and of different sizes in the context of two tasks, semantic textual similarity and natural-language inference. We find that model families differ substantially in their performance and layer dynamics, but that the results are largely model-size invariant.Comment: Accepted to BlackboxNLP 202

    A distributional semantic study on German event nominalizations

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    AbstractWe present the results of a large-scale corpus-based comparison of two German event nominalization patterns: deverbal nouns in -ung (e.g., die Evaluierung, 'the evaluation') and nominal infinitives (e.g., das Evaluieren, 'the evaluating'). Among the many available event nominalization patterns for German, we selected these two because they are both highly productive and challenging from the semantic point of view. Both patterns are known to keep a tight relation with the event denoted by the base verb, but with different nuances. Our study targets a better understanding of the differences in their semantic import.The key notion of our comparison is that of semantic transparency, and we propose a usage-based characterization of the relationship between derived nominals and their bases. Using methods from distributional semantics, we bring to bear two concrete measures of transparency which highlight different nuances: the first one, cosine, detects nominalizations which are semantically similar to their bases; the second one, distributional inclusion, detects nominalizations which are used in a subset of the contexts of the base verb. We find that only the inclusion measure helps in characterizing the difference between the two types of nominalizations, in relation with the traditionally considered variable of relative frequency (Hay, 2001). Finally, the distributional analysis allows us to frame our comparison in the broader coordinates of the inflection vs. derivation cline

    Political claim identification and categorization in a multilingual setting: First experiments

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    The identification and classification of political claims is an important step in the analysis of political newspaper reports; however, resources for this task are few and far between. This paper explores different strategies for the cross-lingual projection of political claims analysis. We conduct experiments on a German dataset, DebateNet2.0, covering the policy debate sparked by the 2015 refugee crisis. Our evaluation involves two tasks (claim identification and categorization), three languages (German, English, and French) and two methods (machine translation -- the best method in our experiments -- and multilingual embeddings).Comment: Presented at KONVENS 2023, Ingolstadt, German

    The integration of syntax and semantic plausibility in a wide-coverage model of human sentence processing

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    Models of human sentence processing have paid much attention to three key characteristics of the sentence processor: Its robust and accurate processing of unseen input (wide coverage), its immediate, incremental interpretation of partial input and its sensitivity to structural frequencies in previous language experience. In this thesis, we propose a model of human sentence processing that accounts for these three characteristics and also models a fourth key characteristic, namely the influence of semantic plausibility on sentence processing. The precondition for such a sentence processing model is a general model of human plausibility intuitions. We therefore begin by presenting a probabilistic model of the plausibility of verb-argument relations, which we estimate as the probability of encountering a verb-argument pair in the relation specified by a thematic role in a role-annotated training corpus. This model faces a significant sparse data problem, which we alleviate by combining two orthogonal smoothing methods. We show that the smoothed model\u27;s predictions are significantly correlated to human plausibility judgements for a range of test sets. We also demonstrate that our semantic plausibility model outperforms selectional preference models and a standard role labeller, which solve tasks from computational linguistics that are related to the prediction of human judgements. We then integrate this semantic plausibility model with an incremental, wide-coverage, probabilistic model of syntactic processing to form the Syntax/Semantics (SynSem) Integration model of sentence processing. The SynSem-Integration model combines preferences for candidate syntactic structures from two sources: Syntactic probability estimates from a probabilistic parser and our semantic plausibility model\u27;s estimates of the verb-argument relations in each syntactic analysis. The model uses these preferences to determine a globally preferred structure and predicts difficulty in human sentence processing either if syntactic and semantic preferences conflict, or if the interpretation of the preferred analysis changes non-monotonically. In a thorough evaluation against the patterns of processing difficulty found for four ambiguity phenomena in eight reading-time studies, we demonstrate that the SynSem-Integration model reliably predicts human reading time behaviour.Diese Dissertation behandelt die Modellierung des menschlichen Sprachverstehens auf der Ebene einzelner Sätze. Während sich bereits existierende Modelle hauptsächlich mit syntaktischen Prozessen befassen, liegt unser Schwerpunkt darauf, ein Modell für die semantische Plausibilität von Äußerungen in ein Satzverarbeitungsmodell zu integrieren. Vier wichtige Eigenschaften des Sprachverstehens bestimmen die Konstruktion unseres Modells: Inkrementelle Verarbeitung, eine erfahrungsbasierte Architektur, breite Abdeckung von Äußerungen, und die Integration von semantischer Plausibilität. Während die ersten drei Eigenschaften von vielen Modellen aufgegriffen werden, gab es bis jetzt kein Modell, das außerdem auch Plausibilität einbezieht. Wir stellen zunächst ein generelles Plausibilitätsmodell vor, um es dann mit einem inkrementellen, probabilistischen Satzverarbeitungsmodell mit breiter Abdeckung zu einem Modell mit allen vier angestrebten Eigenschaften zu integrieren. Unser Plausibilitätsmodell sagt menschliche Plausibilitätsbewertungen für Verb-Argumentpaare in verschiedenen Relationen (z.B. Agens oder Patiens) voraus. Das Modell estimiert die Plausibilität eines Verb-Argumentpaars in einer spezifischen, durch eine thematische Rolle angegebenen Relation als die Wahrscheinlichkeit, das Tripel aus Verb, Argument und Rolle in einem rollensemantisch annotierten Trainingskorpus anzutreffen. Die Vorhersagen des Plausbilitätsmodells korrelieren für eine Reihe verschiedener Testdatensätze signifikant mit menschlichen Plausibilitätsbewertungen. Ein Vergleich mit zwei computerlinguist- ischen Ansätzen, die jeweils eine verwandte Aufgabe erfüllen, nämlich die Zuweisung von thematischen Rollen und die Berechnung von Selektionspräferenzen, zeigt, daß unser Modell Plausibilitätsurteile verläßlicher vorhersagt. Unser Satzverstehensmodell, das Syntax/Semantik-Integrationsmodell, ist eine Kombination aus diesem Plausibilitätsmodell und einem inkrementellen, probabilistischen Satzverarbeitungsmodell auf der Basis eines syntaktischen Parsers mit breiter Abdeckung. Das Syntax/Semantik-Integrationsmodell interpoliert syntaktische Wahrscheinlichkeitsabschätzungen für Analysen einer Äußerung mit den semantischen Plausibilitätsabschätzungen für die Verb-Argumentpaare in jeder Analyse. Das Ergebnis ist eine global präferierte Analyse. Das Syntax/Semantik-Integrationsmodell sagt Verarbeitungsschwierigkeiten voraus, wenn entweder die syntaktisch und semantisch präferierte Analyse konfligieren oder wenn sich die semantische Interpretation der global präferierten Analyse in einem Verarbeitungsschritt nicht-monoton ändert. Die abschließende Evaluation anhand von Befunden über menschliche Verarbeitungsschwierigkeiten, wie sie experimentell in acht Studien für vier Ambiguitätsphänomene festgestellt wurden, zeigt, daß das Syntax/Semantik-Integrationsmodell die experimentellen Daten korrekt voraussagt
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