Year: 2026
Type: conference-paper
Abstract: Intrinsic evaluation metrics for conditional language models, such as perplexity or bits-percharacter, are widely used in both mono-and multilingual settings.These metrics are rather straightforward to use and compare in monolingual setups, but rest on a number of assumptions in multilingual setups.One such assumption is that comparing the perplexity of CLMs on parallel sentences is indicative of their quality since the information content (here understood as the semantic meaning) is the same.However, the metrics are inherently measuring information content in the informationtheoretic sense.Consistency in meaning does not neutralize different forms (paraphrases).We make such assumptions explicit and discuss their implications.We perform experiments with six metrics on two multi-parallel corpora both with mono-and multilingual models.We find that current metrics are not universally comparable and look at the form-meaning debate to provide some explanation for this.
Authors: Wessel Poelman, Miryam de Lhoneux
Institution: KU Leuven
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: hybrid
Award: Fairness in Multilingual NLP
OpenAlex ID: W7140138082
