Daniel Braun


2023

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Efficient Black-Box Adversarial Attacks on Neural Text Detectors
Vitalii Fishchuk | Daniel Braun
Proceedings of the 6th International Conference on Natural Language and Speech Processing (ICNLSP 2023)

2022

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Structured Extraction of Terms and Conditions from German and English Online Shops
Tobias Schamel | Daniel Braun | Florian Matthes
Proceedings of the Fifth Workshop on e-Commerce and NLP (ECNLP 5)

The automated analysis of Terms and Conditions has gained attention in recent years, mainly due to its relevance to consumer protection. Well-structured data sets are the base for every analysis. While content extraction, in general, is a well-researched field and many open source libraries are available, our evaluation shows, that existing solutions cannot extract Terms and Conditions in sufficient quality, mainly because of their special structure. In this paper, we present an approach to extract the content and hierarchy of Terms and Conditions from German and English online shops. Our evaluation shows, that the approach outperforms the current state of the art. A python implementation of the approach is made available under an open license.

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Clause Topic Classification in German and English Standard Form Contracts
Daniel Braun | Florian Matthes
Proceedings of the Fifth Workshop on e-Commerce and NLP (ECNLP 5)

So-called standard form contracts, i.e. contracts that are drafted unilaterally by one party, like terms and conditions of online shops or terms of services of social networks, are cornerstones of our modern economy. Their processing is, therefore, of significant practical value. Often, the sheer size of these contracts allows the drafting party to hide unfavourable terms from the other party. In this paper, we compare different approaches for automatically classifying the topics of clauses in standard form contracts, based on a data-set of more than 6,000 clauses from more than 170 contracts, which we collected from German and English online shops and annotated based on a taxonomy of clause topics, that we developed together with legal experts. We will show that, in our comparison of seven approaches, from simple keyword matching to transformer language models, BERT performed best with an F1-score of up to 0.91, however much simpler and computationally cheaper models like logistic regression also achieved similarly good results of up to 0.87.

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Tracking Semantic Shifts in German Court Decisions with Diachronic Word Embeddings
Daniel Braun
Proceedings of the Natural Legal Language Processing Workshop 2022

Language and its usage change over time. While legal language is arguably more stable than everyday language, it is still subject to change. Sometimes it changes gradually and slowly, sometimes almost instantaneously, for example through legislative changes. This paper presents an application of diachronic word embeddings to track changes in the usage of language by German courts triggered by changing legislation, based on a corpus of more than 200,000 documents. The results show the swift and lasting effect that changes in legislation can have on the usage of language by courts and suggest that using time-restricted word embedding models could be beneficial for downstream NLP tasks.

2021

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NLP for Consumer Protection: Battling Illegal Clauses in German Terms and Conditions in Online Shopping
Daniel Braun | Florian Matthes
Proceedings of the 1st Workshop on NLP for Positive Impact

Online shopping is an ever more important part of the global consumer economy, not just in times of a pandemic. When we place an order online as consumers, we regularly agree to the so-called “Terms and Conditions” (T&C), a contract unilaterally drafted by the seller. Often, consumers do not read these contracts and unwittingly agree to unfavourable and often void terms. Government and non-government organisations (NGOs) for consumer protection battle such terms on behalf of consumers, who often hesitate to take on legal actions themselves. However, the growing number of online shops and a lack of funding makes it increasingly difficult for such organisations to monitor the market effectively. This paper describes how Natural Language Processing (NLP) can be applied to support consumer advocates in their efforts to protect consumers. Together with two NGOs from Germany, we developed an NLP-based application that legally assesses clauses in T&C from German online shops under the European Union’s (EU) jurisdiction. We report that we could achieve an accuracy of 0.9 in the detection of void clauses by fine-tuning a pre-trained German BERT model. The approach is currently used by two NGOs and has already helped to challenge void clauses in T&C.

2020

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MucLex: A German Lexicon for Surface Realisation
Kira Klimt | Daniel Braun | Daniela Schneider | Florian Matthes
Proceedings of the Twelfth Language Resources and Evaluation Conference

Language resources for languages other than English are often scarce. Rule-based surface realisers need elaborate lexica in order to be able to generate correct language, especially in languages like German, which include many irregular word forms. In this paper, we present MucLex, a German lexicon for the Natural Language Generation task of surface realisation, based on the crowd-sourced online lexicon Wiktionary. MucLex contains more than 100,000 lemmata and more than 670,000 different word forms in a well-structured XML file and is available under the Creative Commons BY-SA 3.0 license.

2019

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SimpleNLG-DE: Adapting SimpleNLG 4 to German
Daniel Braun | Kira Klimt | Daniela Schneider | Florian Matthes
Proceedings of the 12th International Conference on Natural Language Generation

SimpleNLG is a popular open source surface realiser for the English language. For German, however, the availability of open source and non-domain specific realisers is sparse, partly due to the complexity of the German language. In this paper, we present SimpleNLG-DE, an adaption of SimpleNLG to German. We discuss which parts of the German language have been implemented and how we evaluated our implementation using the TIGER Corpus and newly created data-sets.

2017

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SaToS: Assessing and Summarising Terms of Services from German Webshops
Daniel Braun | Elena Scepankova | Patrick Holl | Florian Matthes
Proceedings of the 10th International Conference on Natural Language Generation

Every time we buy something online, we are confronted with Terms of Services. However, only a few people actually read these terms, before accepting them, often to their disadvantage. In this paper, we present the SaToS browser plugin which summarises and simplifies Terms of Services from German webshops.

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Evaluating Natural Language Understanding Services for Conversational Question Answering Systems
Daniel Braun | Adrian Hernandez Mendez | Florian Matthes | Manfred Langen
Proceedings of the 18th Annual SIGdial Meeting on Discourse and Dialogue

Conversational interfaces recently gained a lot of attention. One of the reasons for the current hype is the fact that chatbots (one particularly popular form of conversational interfaces) nowadays can be created without any programming knowledge, thanks to different toolkits and so-called Natural Language Understanding (NLU) services. While these NLU services are already widely used in both, industry and science, so far, they have not been analysed systematically. In this paper, we present a method to evaluate the classification performance of NLU services. Moreover, we present two new corpora, one consisting of annotated questions and one consisting of annotated questions with the corresponding answers. Based on these corpora, we conduct an evaluation of some of the most popular NLU services. Thereby we want to enable both, researchers and companies to make more educated decisions about which service they should use.

2015

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Creating Textual Driver Feedback from Telemetric Data
Daniel Braun | Ehud Reiter | Advaith Siddharthan
Proceedings of the 15th European Workshop on Natural Language Generation (ENLG)