Transfer learning has fundamentally changed the landscape of natural language
processing (NLP) research. Many existing state-of-the-art models are first
pre-trained on a large text corpus and then fine-tuned on downstream tasks.
However, due to limited data resources from downstream tasks and the extremely
large capacity of pre-trained models, aggressive fine-tuning often causes the
adapted model to overfit the data of downstream tasks and forget the knowledge
of the pre-trained model. To address the above issue in a more principled
manner, we propose a new computational framework for robust and efficient
fine-tuning for pre-trained language models. Specifically, our proposed
framework contains two important ingredients: 1. Smoothness-inducing
regularization, which effectively manages the capacity of the model; 2. Bregman
proximal point optimization, which is a class of trust-region methods and can
prevent knowledge forgetting. Our experiments demonstrate that our proposed
method achieves the state-of-the-art performance on multiple NLP benchmarks.

本文提出一种基于 Bregman 的 Trust-Region 优化的平滑正则化框架，用于更加有效地对预训练语言模型进行微调，避免过拟合和知识遗忘，通过实验表明在多项 NLP benchmarks 上达到了最新的性能水平。