Timm Lichte


2023

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PARSEME corpus release 1.3
Agata Savary | Cherifa Ben Khelil | Carlos Ramisch | Voula Giouli | Verginica Barbu Mititelu | Najet Hadj Mohamed | Cvetana Krstev | Chaya Liebeskind | Hongzhi Xu | Sara Stymne | Tunga Güngör | Thomas Pickard | Bruno Guillaume | Eduard Bejček | Archna Bhatia | Marie Candito | Polona Gantar | Uxoa Iñurrieta | Albert Gatt | Jolanta Kovalevskaite | Timm Lichte | Nikola Ljubešić | Johanna Monti | Carla Parra Escartín | Mehrnoush Shamsfard | Ivelina Stoyanova | Veronika Vincze | Abigail Walsh
Proceedings of the 19th Workshop on Multiword Expressions (MWE 2023)

We present version 1.3 of the PARSEME multilingual corpus annotated with verbal multiword expressions. Since the previous version, new languages have joined the undertaking of creating such a resource, some of the already existing corpora have been enriched with new annotated texts, while others have been enhanced in various ways. The PARSEME multilingual corpus represents 26 languages now. All monolingual corpora therein use Universal Dependencies v.2 tagset. They are (re-)split observing the PARSEME v.1.2 standard, which puts impact on unseen VMWEs. With the current iteration, the corpus release process has been detached from shared tasks; instead, a process for continuous improvement and systematic releases has been introduced.

2022

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An Analysis of Attention in German Verbal Idiom Disambiguation
Rafael Ehren | Laura Kallmeyer | Timm Lichte
Proceedings of the 18th Workshop on Multiword Expressions @LREC2022

In this paper we examine a BiLSTM architecture for disambiguating verbal potentially idiomatic expressions (PIEs) as to whether they are used in a literal or an idiomatic reading with respect to explainability of its decisions. Concretely, we extend the BiLSTM with an additional attention mechanism and track the elements that get the highest attention. The goal is to better understand which parts of an input sentence are particularly discriminative for the classifier’s decision, based on the assumption that these elements receive a higher attention than others. In particular, we investigate POS tags and dependency relations to PIE verbs for the tokens with the maximal attention. It turns out that the elements with maximal attention are oftentimes nouns that are the subjects of the PIE verb. For longer sentences however (i.e., sentences containing, among others, more modifiers), the highest attention word often stands in a modifying relation to the PIE components. This is particularly frequent for PIEs classified as literal. Our study shows that an attention mechanism can contribute to the explainability of classification decisions that depend on specific cues in the sentential context, as it is the case for PIE disambiguation.

2020

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Supervised Disambiguation of German Verbal Idioms with a BiLSTM Architecture
Rafael Ehren | Timm Lichte | Laura Kallmeyer | Jakub Waszczuk
Proceedings of the Second Workshop on Figurative Language Processing

Supervised disambiguation of verbal idioms (VID) poses special demands on the quality and quantity of the annotated data used for learning and evaluation. In this paper, we present a new VID corpus for German and perform a series of VID disambiguation experiments on it. Our best classifier, based on a neural architecture, yields an error reduction across VIDs of 57% in terms of accuracy compared to a simple majority baseline.

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Edition 1.2 of the PARSEME Shared Task on Semi-supervised Identification of Verbal Multiword Expressions
Carlos Ramisch | Agata Savary | Bruno Guillaume | Jakub Waszczuk | Marie Candito | Ashwini Vaidya | Verginica Barbu Mititelu | Archna Bhatia | Uxoa Iñurrieta | Voula Giouli | Tunga Güngör | Menghan Jiang | Timm Lichte | Chaya Liebeskind | Johanna Monti | Renata Ramisch | Sara Stymne | Abigail Walsh | Hongzhi Xu
Proceedings of the Joint Workshop on Multiword Expressions and Electronic Lexicons

We present edition 1.2 of the PARSEME shared task on identification of verbal multiword expressions (VMWEs). Lessons learned from previous editions indicate that VMWEs have low ambiguity, and that the major challenge lies in identifying test instances never seen in the training data. Therefore, this edition focuses on unseen VMWEs. We have split annotated corpora so that the test corpora contain around 300 unseen VMWEs, and we provide non-annotated raw corpora to be used by complementary discovery methods. We released annotated and raw corpora in 14 languages, and this semi-supervised challenge attracted 7 teams who submitted 9 system results. This paper describes the effort of corpus creation, the task design, and the results obtained by the participating systems, especially their performance on unseen expressions.

2018

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Edition 1.1 of the PARSEME Shared Task on Automatic Identification of Verbal Multiword Expressions
Carlos Ramisch | Silvio Ricardo Cordeiro | Agata Savary | Veronika Vincze | Verginica Barbu Mititelu | Archna Bhatia | Maja Buljan | Marie Candito | Polona Gantar | Voula Giouli | Tunga Güngör | Abdelati Hawwari | Uxoa Iñurrieta | Jolanta Kovalevskaitė | Simon Krek | Timm Lichte | Chaya Liebeskind | Johanna Monti | Carla Parra Escartín | Behrang QasemiZadeh | Renata Ramisch | Nathan Schneider | Ivelina Stoyanova | Ashwini Vaidya | Abigail Walsh
Proceedings of the Joint Workshop on Linguistic Annotation, Multiword Expressions and Constructions (LAW-MWE-CxG-2018)

This paper describes the PARSEME Shared Task 1.1 on automatic identification of verbal multiword expressions. We present the annotation methodology, focusing on changes from last year’s shared task. Novel aspects include enhanced annotation guidelines, additional annotated data for most languages, corpora for some new languages, and new evaluation settings. Corpora were created for 20 languages, which are also briefly discussed. We report organizational principles behind the shared task and the evaluation metrics employed for ranking. The 17 participating systems, their methods and obtained results are also presented and analysed.

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Mumpitz at PARSEME Shared Task 2018: A Bidirectional LSTM for the Identification of Verbal Multiword Expressions
Rafael Ehren | Timm Lichte | Younes Samih
Proceedings of the Joint Workshop on Linguistic Annotation, Multiword Expressions and Constructions (LAW-MWE-CxG-2018)

In this paper, we describe Mumpitz, the system we submitted to the PARSEME Shared task on automatic identification of verbal multiword expressions (VMWEs). Mumpitz consists of a Bidirectional Recurrent Neural Network (BRNN) with Long Short-Term Memory (LSTM) units and a heuristic that leverages the dependency information provided in the PARSEME corpus data to differentiate VMWEs in a sentence. We submitted results for seven languages in the closed track of the task and for one language in the open track. For the open track we used the same system, but with pretrained instead of randomly initialized word embeddings to improve the system performance.

2017

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Depictives in English: An LTAG Approach
Benjamin Burkhardt | Timm Lichte | Laura Kallmeyer
Proceedings of the 13th International Workshop on Tree Adjoining Grammars and Related Formalisms

2016

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Discontinuous parsing with continuous trees
Wolfgang Maier | Timm Lichte
Proceedings of the Workshop on Discontinuous Structures in Natural Language Processing

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Argument linking in LTAG: A constraint-based implementation with XMG
Laura Kallmeyer | Timm Lichte | Rainer Osswald | Simon Petitjean
Proceedings of the 12th International Workshop on Tree Adjoining Grammars and Related Formalisms (TAG+12)

2015

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Une métagrammaire de l’interface morpho-sémantique dans les verbes en arabe
Simon Petitjean | Younes Samih | Timm Lichte
Actes de la 22e conférence sur le Traitement Automatique des Langues Naturelles. Articles courts

Dans cet article, nous présentons une modélisation de la morphologie dérivationnelle de l’arabe utilisant le cadre métagrammatical offert par XMG. Nous démontrons que l’utilisation de racines et patrons abstraits comme morphèmes atomiques sous-spécifiés offre une manière élégante de traiter l’interaction entre morphologie et sémantique.

2012

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Synchronous Tree Unification Grammar
Timm Lichte
Proceedings of the 11th International Workshop on Tree Adjoining Grammars and Related Formalisms (TAG+11)

2010

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From Partial VP Fronting towards Spinal TT-MCTAG
Timm Lichte
Proceedings of the 10th International Workshop on Tree Adjoining Grammar and Related Frameworks (TAG+10)

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Gapping through TAG derivation trees
Timm Lichte | Laura Kallmeyer
Proceedings of the 10th International Workshop on Tree Adjoining Grammar and Related Frameworks (TAG+10)

2008

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Developing a TT-MCTAG for German with an RCG-based Parser
Laura Kallmeyer | Timm Lichte | Wolfgang Maier | Yannick Parmentier | Johannes Dellert
Proceedings of the Sixth International Conference on Language Resources and Evaluation (LREC'08)

Developing linguistic resources, in particular grammars, is known to be a complex task in itself, because of (amongst others) redundancy and consistency issues. Furthermore some languages can reveal themselves hard to describe because of specific characteristics, e.g. the free word order in German. In this context, we present (i) a framework allowing to describe tree-based grammars, and (ii) an actual fragment of a core multicomponent tree-adjoining grammar with tree tuples (TT-MCTAG) for German developed using this framework. This framework combines a metagrammar compiler and a parser based on range concatenation grammar (RCG) to respectively check the consistency and the correction of the grammar. The German grammar being developed within this framework already deals with a wide range of scrambling and extraction phenomena.

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TuLiPA: Towards a Multi-Formalism Parsing Environment for Grammar Engineering
Laura Kallmeyer | Timm Lichte | Wolfgang Maier | Yannick Parmentier | Johannes Dellert | Kilian Evang
Coling 2008: Proceedings of the workshop on Grammar Engineering Across Frameworks

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Factorizing Complementation in a TT-MCTAG for German
Timm Lichte | Laura Kallmeyer
Proceedings of the Ninth International Workshop on Tree Adjoining Grammar and Related Frameworks (TAG+9)

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TuLiPA: A syntax-semantics parsing environment for mildly context-sensitive formalisms
Yannick Parmentier | Laura Kallmeyer | Wolfgang Maier | Timm Lichte | Johannes Dellert
Proceedings of the Ninth International Workshop on Tree Adjoining Grammar and Related Frameworks (TAG+9)

2006

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Licensing German Negative Polarity Items in LTAG
Timm Lichte | Laura Kallmeyer
Proceedings of the Eighth International Workshop on Tree Adjoining Grammar and Related Formalisms