The Role of Language Imbalance in Cross-lingual Generalisation: Insights from Cloned Language Experiments

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Schäfer, Anton, Ravfogel, Shauli, Hofmann, Thomas, Pimentel, Tiago, Schlag, Imanol
Format: Preprint
Veröffentlicht: 2024
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866913433739329536
author Schäfer, Anton
Ravfogel, Shauli
Hofmann, Thomas
Pimentel, Tiago
Schlag, Imanol
author_facet Schäfer, Anton
Ravfogel, Shauli
Hofmann, Thomas
Pimentel, Tiago
Schlag, Imanol
contents Multilinguality is crucial for extending recent advancements in language modelling to diverse linguistic communities. To maintain high performance while representing multiple languages, multilingual models ideally align representations, allowing what is learned in one language to generalise to others. Prior research has emphasised the importance of parallel data and shared vocabulary elements as key factors for such alignment. In this study, we investigate an unintuitive novel driver of cross-lingual generalisation: language imbalance. In controlled experiments on perfectly equivalent cloned languages, we observe that the existence of a predominant language during training boosts the performance of less frequent languages and leads to stronger alignment of model representations across languages. Furthermore, we find that this trend is amplified with scale: with large enough models or long enough training, we observe that bilingual training data with a 90/10 language split yields better performance on both languages than a balanced 50/50 split. Building on these insights, we design training schemes that can improve performance in all cloned languages, even without altering the training data. As we extend our analysis to real languages, we find that infrequent languages still benefit from frequent ones, yet whether language imbalance causes cross-lingual generalisation there is not conclusive.
format Preprint
id arxiv_https___arxiv_org_abs_2404_07982
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle The Role of Language Imbalance in Cross-lingual Generalisation: Insights from Cloned Language Experiments
Schäfer, Anton
Ravfogel, Shauli
Hofmann, Thomas
Pimentel, Tiago
Schlag, Imanol
Computation and Language
Machine Learning
I.2.7
Multilinguality is crucial for extending recent advancements in language modelling to diverse linguistic communities. To maintain high performance while representing multiple languages, multilingual models ideally align representations, allowing what is learned in one language to generalise to others. Prior research has emphasised the importance of parallel data and shared vocabulary elements as key factors for such alignment. In this study, we investigate an unintuitive novel driver of cross-lingual generalisation: language imbalance. In controlled experiments on perfectly equivalent cloned languages, we observe that the existence of a predominant language during training boosts the performance of less frequent languages and leads to stronger alignment of model representations across languages. Furthermore, we find that this trend is amplified with scale: with large enough models or long enough training, we observe that bilingual training data with a 90/10 language split yields better performance on both languages than a balanced 50/50 split. Building on these insights, we design training schemes that can improve performance in all cloned languages, even without altering the training data. As we extend our analysis to real languages, we find that infrequent languages still benefit from frequent ones, yet whether language imbalance causes cross-lingual generalisation there is not conclusive.
title The Role of Language Imbalance in Cross-lingual Generalisation: Insights from Cloned Language Experiments
topic Computation and Language
Machine Learning
I.2.7
url https://arxiv.org/abs/2404.07982