Koherenssimalleja

Koherenssimalleja are theoretical and computational frameworks for describing how the parts of a text or discourse hang together to form a coherent whole. In linguistics and natural language processing, these models aim to explain and predict how readers interpret connections between sentences, events, and participants, and how this coherence influences meaning and reception. The term is commonly used in Finnish-language discussions of discourse theory and NLP.

The main traditions of coherence modeling include Rhetorical Structure Theory (RST), Centering Theory, and Discourse Representation Theory (DRT) and its variants such as SDRT. RST treats a text as a hierarchical structure of discourse relations—such as elaboration, explanation, or contrast—between discourse units. Centering Theory emphasizes local coherence through the continuity of focus and reference, modeling how pronouns and nouns maintain or shift attention. SDRT and related frameworks formalize coherence with underspecified, compositional representations that encode discourse relations, anaphora, and temporal or modal information, allowing flexible analysis across longer stretches of text.

In computational linguistics, koherenssimalleja underpin tasks such as discourse parsing, automatic summarization, text generation, machine translation, and coherence-aware evaluation. Features include recognized discourse relations, referential continuity, topic progression, and argument structure, often integrated with statistical or neural models to improve readability and consistency of generated text.

Challenges include the subjective nature of coherence, cross-linguistic variation in discourse conventions, and the difficulty of evaluating coherence automatically. Ongoing work explores hybrid symbolic-neural approaches, cross-document coherence, and applications in multilingual NLP. The term reflects ongoing interest in formalizing how discourse structure shapes meaning, both in Finnish-language research and in the broader international literature on coherence modeling.