Anaphoricity in connectives: From corpus analysis to lexical description and consequences for discourse parsing

在语言中，语篇连接词用来表示两个语段之间是否存在连贯关系，如因果关系、时间关系或对比关系。从句法角度看，连接词可以是连词，也可以是某些状语。虽然连词已经在不同层次的描述上得到了深入的研究，但关于话语状语与它们的论点（相关的文本片段）的映射以及它们在构建话语结构中的作用，这对读者来说是很重要的，例如在解决回指代词时。在我们对语篇状语的研究中，回指的概念发挥了核心作用，在许多连接词中，这是由一个明显的回指语素给出的。我们的项目采用双语视角，使用德语、英语和平行双语文本语料库，在第一步，研究这些连接词的使用条件：当一个连接词可以表示不同的连贯关系时，读者如何处理歧义？在阅读过程中，如果文本中没有明确给出连接词的论点，在什么情况下，通过什么方式被“构建”？读者如何确定相关文本片段的边界-何时它们被清楚地识别出来，何时它们仍然相当模糊，例如可能发生在句子开头的“但是”？读者如何处理同一句子中出现的多个连接词之间潜在的复杂互动？研究两种语言的这些问题，一方面可以对德语和英语的连接词进行系统的比较；另一方面，拓宽了话语状语对语篇结构层次影响的视角。早期的实证工作主要是在英国数据上完成的；然而，如果可能的话，应该从多语言的角度来研究话语结构因素。我们计划通过与早期英语成绩的比较来实现这一目标。此外，结果将被转移到自动文本分析（“文本挖掘”）中。为此，为单个连接词收集的信息将在正式的词典条目中建模，然后由自动话语解析器使用；这种系统的原型将作为项目的一部分被开发出来。

In language, discourse connectives are used to signal the presence of coherence relations between two text segments, such as causal, temporal or contrastive relationships. From the syntactic viewpoint, connectives can be conjunctions or certain adverbials. While conjunctions have been studied intensively on various levels of description, many questions are open for the discourse adverbials, regarding the mapping to their arguments (the text segments being related) and their role for constructing the discourse structure, which in turn is important for the reader, e.g. when resolving anaphoric pronouns.A central role in our investigations of discourse adverbials is played by the notion of anaphoricity, which in many connectives is given by an overt anaphoric morpheme. Our project adopts a bilingual perspective and uses German, English, and parallel bilingual text corpora for, in the first step, studying the usage conditions of these connectives: How do readers handle ambiguities, when a connective can signal different coherence relations? Under what circumstances and by what means is an argument of a connective being "constructed" during reading, in case it is not explicitly given in the text? How do readers determine the boundaries of the text segments being related - when are they identified clearly, and when do they remain rather vague, as it can happen for instance with a sentence-initial "but"? How do readers cope with potentially complex interactions between multiple connectives present within the same sentence?Studying these questions for two languages on the one hand allows for systematic comparison of German and English connectives; on the other hand it broadens the perspective for the consequences that discourse adverbials have for the level of discourse structure. Earlier empirical work has been done largely on English data; yet discourse-structural factors should be studied from a multi-lingual perspective if possible. We plan to accomplish this through comparisons to the earlier results for English.In addition, the results will be transferred to work in automatic text analysis ("text mining"). To this end, the information gathered for individual connectives will be modeled in formal lexicon entries that can then be used by an automatic discourse parser; a prototype of such a system will be developed as part of the project.