Toward a Treebank Collecting German Aesthetic Writings,of the Late 18th Century
Authors: Alessio Salomoni (Università di Pavia, Univeristà di Bergamo, 2017)
Topic: Syntax and Dependency Treebanks

Abstract
In this paper, I will describe the methodology to develop the first sample of a dependency treebank collecting German aesthetic writings of the late 18\textsuperscript{th} century. A gold standard of the target data was annotated in order to evaluate some data-driven tools, trained on contemporary web news. Results are reported and discussed.

Introduction
A constantly increasing amount of digital texts of the German literary history is freely available online as downloadable raw texts, especially thanks to important ongoing projects, such as deutschestextarchiv.de or zeno.org, to name but a few. In spite of this, we still lack annotated corpora gathering them per author and genre. Indeed, this is a strong bottleneck in exploiting such textual treasure for linguistic analysis through computational methods. At the same time, available training data for data-driven annotation tools mainly come from the domain of contemporary web news. Therefore, models have to be trained on this particular variety of the German language, which could be very different, in terms of linguistic features, from the target unannotated data. Such variation between the training set and the test set could cause tools' performances to drop AUTHOR. Therefore, testing such models on a portion of the target texts is crucial. On the one hand, to show their robustness. On the other hand, more practically, to understand to what extent available tools can actually boost the semi-automatic annotation of new data.\\ In this paper, I will highlight the methodology behind the development of a first sample of a dependency treebank aiming to collect German aesthetic essays of the late 18\textsuperscript{th} century. By aesthetic essays I mean theoretical writings about art, poetics, beauty and related issues, which were mainly published on literary magazines, chiefly targeting non-academic middle-class readers. In that period, there was a remarkable production of these texts in Germany, and they contributed to popularize the recently born modern 'Hochdeutsch', i.e. the modern variety of the German language. To the best of my knowledge, despite its importance, such textual genre has never been studied in depth at any linguistic level. In a long-term perspective, a dependency treebank will surely provide empirical data to fill the gap, especially concerning syntax and semantics. Indeed, many studies can be done on such resource, ranging from using dependency networks to describe syntactic phenomena AUTHOR, to extracting a valency lexicon AUTHOR.\\ In the rest of this paper, some fundamental issues concerning the treebank design are highlighted and preliminary results concerning automatic lemmatization, POS-tagging and dependency parsing are reported and discussed.

Conclusion
In this work, I described the methodology behind the development of a first sample of a German treebank collecting a particular kind of aesthetic essays from the late 18th century, called fragments. A gold standard was annotated adhering to UD 2.0. Then some data-driven tools were tested either on the target data and on a test set of the source variety. Some core issues concerning the automatic annotation were highlighted. As for LEMMA and XPOS, overall accuracy on the target data was high and very close to that on the source variety. As for UPOS, the accuracy by the best tagger dropped, especially on the target data. Therefore, to assign POS-tag, the very good results on the STTS tagset may suggest to automatically assign XPOS first and then derive UPOS from XPOS. Furthermore, the influence of POS-tagging granularity on parsing has not been studied yet. As for dependency parsing, the overall gap between the target variety and the source variety was remarkable (19%). An in-depth comparison between the two varieties concerning single relations will surely help to better detect parsing problems on fragments. In addition, parsing manually lemmatized and POS-tagged texts will surely shed light on the error propagation on parsing.