Tatjana Scheffler


2019

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Team Kit Kittredge at SemEval-2019 Task 4: LSTM Voting System
Rebekah Cramerus | Tatjana Scheffler
Proceedings of the 13th International Workshop on Semantic Evaluation

This paper describes the approach of team Kit Kittredge to SemEval-2019 Task 4: Hyperpartisan News Detection. The goal was binary classification of news articles into the categories of “biased” or “unbiased”. We had two software submissions: one a simple bag-of-words model, and the second an LSTM (Long Short Term Memory) neural network, which was trained on a subset of the original dataset selected by a voting system of other LSTMs. This method did not prove much more successful than the baseline, however, due to the models’ tendency to learn publisher-specific traits instead of general bias.

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Ranking of Potential Questions
Luise Schricker | Tatjana Scheffler
Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics: Student Research Workshop

Questions are an integral part of discourse. They provide structure and support the exchange of information. One linguistic theory, the Questions Under Discussion model, takes question structures as integral to the functioning of a coherent discourse. This theory has not been tested on the count of its validity for predicting observations in real dialogue data, however. In this submission, a system for ranking explicit and implicit questions by their appropriateness in a dialogue is presented. This system implements constraints and principles put forward in the linguistic literature.

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Annotating Shallow Discourse Relations in Twitter Conversations
Tatjana Scheffler | Berfin Aktaş | Debopam Das | Manfred Stede
Proceedings of the Workshop on Discourse Relation Parsing and Treebanking 2019

We introduce our pilot study applying PDTB-style annotation to Twitter conversations. Lexically grounded coherence annotation for Twitter threads will enable detailed investigations of the discourse structure of conversations on social media. Here, we present our corpus of 185 threads and annotation, including an inter-annotator agreement study. We discuss our observations as to how Twitter discourses differ from written news text wrt. discourse connectives and relations. We confirm our hypothesis that discourse relations in written social media conversations are expressed differently than in (news) text. We find that in Twitter, connective arguments frequently are not full syntactic clauses, and that a few general connectives expressing EXPANSION and CONTINGENCY make up the majority of the explicit relations in our data.

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Can Neural Image Captioning be Controlled via Forced Attention?
Philipp Sadler | Tatjana Scheffler | David Schlangen
Proceedings of the 12th International Conference on Natural Language Generation

Learned dynamic weighting of the conditioning signal (attention) has been shown to improve neural language generation in a variety of settings. The weights applied when generating a particular output sequence have also been viewed as providing a potentially explanatory insight in the internal workings of the generator. In this paper, we reverse the direction of this connection and ask whether through the control of the attention of the model we can control its output. Specifically, we take a standard neural image captioning model that uses attention, and fix the attention to predetermined areas in the image. We evaluate whether the resulting output is more likely to mention the class of the object in that area than the normally generated caption. We introduce three effective methods to control the attention and find that these are producing expected results in up to 27.43% of the cases.

2018

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Anaphora Resolution for Twitter Conversations: An Exploratory Study
Berfin Aktaş | Tatjana Scheffler | Manfred Stede
Proceedings of the First Workshop on Computational Models of Reference, Anaphora and Coreference

We present a corpus study of pronominal anaphora on Twitter conversations. After outlining the specific features of this genre, with respect to reference resolution, we explain the construction of our corpus and the annotation steps. From this we derive a list of phenomena that need to be considered when performing anaphora resolution on this type of data. Finally, we test the performance of an off-the-shelf resolution system, and provide some qualitative error analysis.

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Constructing a Lexicon of English Discourse Connectives
Debopam Das | Tatjana Scheffler | Peter Bourgonje | Manfred Stede
Proceedings of the 19th Annual SIGdial Meeting on Discourse and Dialogue

We present a new lexicon of English discourse connectives called DiMLex-Eng, built by merging information from two annotated corpora and an additional list of relation signals from the literature. The format follows the German connective lexicon DiMLex, which provides a cross-linguistically applicable XML schema. DiMLex-Eng contains 149 English connectives, and gives information on syntactic categories, discourse semantics and non-connective uses (if any). We report on the development steps and discuss design decisions encountered in the lexicon expansion phase. The resource is freely available for use in studies of discourse structure and computational applications.

2017

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Proceedings of the 13th International Workshop on Tree Adjoining Grammars and Related Formalisms
Marco Kuhlmann | Tatjana Scheffler
Proceedings of the 13th International Workshop on Tree Adjoining Grammars and Related Formalisms

2016

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Adding Semantic Relations to a Large-Coverage Connective Lexicon of German
Tatjana Scheffler | Manfred Stede
Proceedings of the Tenth International Conference on Language Resources and Evaluation (LREC'16)

DiMLex is a lexicon of German connectives that can be used for various language understanding purposes. We enhanced the coverage to 275 connectives, which we regard as covering all known German discourse connectives in current use. In this paper, we consider the task of adding the semantic relations that can be expressed by each connective. After discussing different approaches to retrieving semantic information, we settle on annotating each connective with senses from the new PDTB 3.0 sense hierarchy. We describe our new implementation in the extended DiMLex, which will be available for research purposes.

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OPT: Oslo–Potsdam–Teesside. Pipelining Rules, Rankers, and Classifier Ensembles for Shallow Discourse Parsing
Stephan Oepen | Jonathon Read | Tatjana Scheffler | Uladzimir Sidarenka | Manfred Stede | Erik Velldal | Lilja Øvrelid
Proceedings of the CoNLL-16 shared task

2015

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Dialog Act Annotation for Twitter Conversations
Elina Zarisheva | Tatjana Scheffler
Proceedings of the 16th Annual Meeting of the Special Interest Group on Discourse and Dialogue

2014

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A German Twitter Snapshot
Tatjana Scheffler
Proceedings of the Ninth International Conference on Language Resources and Evaluation (LREC'14)

We present a new corpus of German tweets. Due to the relatively small number of German messages on Twitter, it is possible to collect a virtually complete snapshot of German twitter messages over a period of time. In this paper, we present our collection method which produced a 24 million tweet corpus, representing a large majority of all German tweets sent in April, 2013. Further, we analyze this representative data set and characterize the German twitterverse. While German Twitter data is similar to other Twitter data in terms of its temporal distribution, German Twitter users are much more reluctant to share geolocation information with their tweets. Finally, the corpus collection method allows for a study of discourse phenomena in the Twitter data, structured into discussion threads.

2008

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Flexible Composition and Delayed Tree-Locality
David Chiang | Tatjana Scheffler
Proceedings of the Ninth International Workshop on Tree Adjoining Grammar and Related Frameworks (TAG+9)

2006

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The Metagrammar Goes Multilingual: A Cross-Linguistic Look at the V2-Phenomenon
Alexandra Kinyon | Owen Rambow | Tatjana Scheffler | SinWon Yoon | Aravind K. Joshi
Proceedings of the Eighth International Workshop on Tree Adjoining Grammar and Related Formalisms

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Binding of Anaphors in LTAG
Neville Ryant | Tatjana Scheffler
Proceedings of the Eighth International Workshop on Tree Adjoining Grammar and Related Formalisms

2004

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LTAG Analysis for Pied-Piping and Stranding of wh-Phrases
Laura Kallmeyer | Tatjana Scheffler
Proceedings of the 7th International Workshop on Tree Adjoining Grammar and Related Formalisms

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Semantic Reconstruction for how many-Questions in LTAG
Tatjana Scheffler
Proceedings of the 7th International Workshop on Tree Adjoining Grammar and Related Formalisms