Large Language Models Are State-of-the-Art Evaluator for Grammatical Error Correction
Masamune Kobayashi, Masato Mita, Mamoru Komachi
TL;DR
This work investigates large language models as evaluators for English grammatical error correction (GEC) by designing prompts that encode evaluation criteria and by performing comprehensive meta-evaluation against traditional metrics. Using the SEEDA dataset, the authors compare system-level and sentence-level correlations between human judgments and LLM-based scores across EBMs/SBMs, revealing that GPT-4 achieves state-of-the-art alignment, with a Kendall's tau around $0.662$. The study highlights that model scale and fluency-focused prompts substantially improve evaluation performance, while smaller models show reduced sensitivity to fluency and tend to cluster scores. The findings support LLM-based evaluation as a robust, scalable alternative to conventional GEC metrics and outline future work on few-shot prompting and document-level assessment.
Abstract
Large Language Models (LLMs) have been reported to outperform existing automatic evaluation metrics in some tasks, such as text summarization and machine translation. However, there has been a lack of research on LLMs as evaluators in grammatical error correction (GEC). In this study, we investigate the performance of LLMs in GEC evaluation by employing prompts designed to incorporate various evaluation criteria inspired by previous research. Our extensive experimental results demonstrate that GPT-4 achieved Kendall's rank correlation of 0.662 with human judgments, surpassing all existing methods. Furthermore, in recent GEC evaluations, we have underscored the significance of the LLMs scale and particularly emphasized the importance of fluency among evaluation criteria.
