MacBERTh: Development and Evaluation of a Historically Pre-trained Language Model for English (1450-1950)

Abstract

The new pre-train-then-fine-tune paradigm in Natural Language Processing (NLP) has made important performance gains accessible to a wider audience. Once pre-trained, deploying a large language model presents comparatively small infrastructure requirements, and offers robust performance in many NLP tasks. The Digital Humanities (DH) community has been an early adapter of this paradigm. Yet, a large part of this community is concerned with the application of NLP algorithms to historical texts, for which large models pre-trained on contemporary text may not provide optimal results. In the present paper, we present “MacBERTh”—a transformer-based language model pre-trained on historical English—and exhaustively assess its benefits on a large set of relevant downstream tasks. Our experiments highlight that, despite some differences across target time periods, pre-training on historical language from scratch outperforms models pre-trained on present-day language and later adapted to historical language. [Note: The updated and extended version of this paper is: “Adapting vs Pre-training Language Models for Historical Languages”]

Publication
In Proceedings of the International Workshop on Natural Language Processing for Digital Humanities (NLP4DH)

Evaluation code is available through the project’s repository. “MacBERTh” itself is available as emanjavacas/MacBERTh from the transformers repository (Wolf et al. 2019).