Björn Nieth
Author directory2026
How Human-Like Are Large Language Models? A Register-Aware Linguistic Evaluation Framework
Björn Nieth | Marianna Gracheva | Michaela Mahlberg | Bjoern Eskofier | Emmanuelle Salin
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Björn Nieth | Marianna Gracheva | Michaela Mahlberg | Bjoern Eskofier | Emmanuelle Salin
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
While factual correctness and task-performance have received much attention by Large Language Model (LLM) research, the fundamental question of how human-like generated texts are on a linguistic level has been underexplored. From a corpus-linguistic perspective, language production is inherently context-dependent. Distinct communicative contexts give rise to differences in frequencies and co-occurrence patterns of linguistic features that shape registers of language use. A text failing to adhere to these patterns can be correct content-wise, but still may not appear natural to human readers. In this work, we propose a context-aware evaluation framework in which human-likeness is measured as a two-sample problem between the linguistic feature distribution of a human reference corpus for a given register and a corresponding LLM-generated corpus. We implement this framework using the Maximum Mean Discrepancy (MMD) measure and the 67 lexico-grammatical features introduced by Biber, which are commonly applied in corpus linguistics.
In our experiments, we compare seven instruction-tuned, open-source models and look at five English-language datasets spanning distinct registers. While across all tested setups, LLMs deviate from the human baseline, which models are closest to human language depends on the register and is not dictated by model size.
In our experiments, we compare seven instruction-tuned, open-source models and look at five English-language datasets spanning distinct registers. While across all tested setups, LLMs deviate from the human baseline, which models are closest to human language depends on the register and is not dictated by model size.
How LLMs Build Fictional Worlds: Setting and Narrative Space in AI-Generated Creative Storytelling
Katrin Rohrbacher | Björn Nieth | Emmanuelle Salin | Bjoern Eskofier | Michaela Mahlberg
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Katrin Rohrbacher | Björn Nieth | Emmanuelle Salin | Bjoern Eskofier | Michaela Mahlberg
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
In this paper, we analyze how Large Language Models (LLMs) employ worldbuilding strategies, focusing on setting as one measurable dimension of storyworld construction. We compare 1,000 AI-generated stories per model in English and German with human-authored fiction from Project Gutenberg. Building on prior work, we operationalize setting through five types of narrative space: "action," "perceived," "visual," "descriptive" and "no space", identified using fine-tuned BERT classifiers for German and English. We generate narratives using GPT 4.1, LlaMA 3.3, Mistral 3.2, and Gemma 3 and compare their spatial distributions to a human-authored baseline. We find that human-authored texts predominantly employ "action space," grounding narratives in embodied character-environment interaction, whereas LLMs systematically overproduce "perceived space," emphasizing atmosphere and affect. This divergence remains stable across narrative time. Overall, our findings show that LLMs exhibit worldbuilding patterns that differ consistently from human-authored fiction in ways that are both model-specific and language-sensitive.