An Embarrassingly Simple Approach for Transfer Learning from Pretrained Language Models
Alexandra Chronopoulou, Christos Baziotis, Alexandros Potamianos
TL;DR
This work tackles transferring from pretrained language models for text classification without catastrophic forgetting. It proposes SiATL, which transfers a pretrained LM, appends a task-specific recurrent layer with self-attention, and trains with a joint objective $L = L_{task} + \gamma L_{LM}$ where $\gamma$ decays exponentially, plus a sequential unfreezing schedule to gradually expose pretrained layers. Across five affective and classification datasets, SiATL outperforms strong baselines such as ULMFiT, particularly in low-data regimes, while remaining end-to-end and simple to train. The approach demonstrates that a lightweight, single-step transfer-learning pipeline can match or exceed state-of-the-art results without extensive learning-rate scheduling or separate pretraining steps, with code to be released in a future version.
Abstract
A growing number of state-of-the-art transfer learning methods employ language models pretrained on large generic corpora. In this paper we present a conceptually simple and effective transfer learning approach that addresses the problem of catastrophic forgetting. Specifically, we combine the task-specific optimization function with an auxiliary language model objective, which is adjusted during the training process. This preserves language regularities captured by language models, while enabling sufficient adaptation for solving the target task. Our method does not require pretraining or finetuning separate components of the network and we train our models end-to-end in a single step. We present results on a variety of challenging affective and text classification tasks, surpassing well established transfer learning methods with greater level of complexity.
