DEFT: Data Efficient Fine-Tuning for Pre-Trained Language Models via Unsupervised Core-Set Selection
Devleena Das, Vivek Khetan
TL;DR
The paper tackles data efficiency in fine-tuning pre-trained language models for text-editing by proposing DEFT-UCS, which uses unsupervised core-set selection to form a compact yet representative training subset $D_c$ from a larger dataset $D$. It builds a pipeline where a base set $D_{base}$ is augmented with $D_c$ derived from clustering embeddings (notably via Sentence-T5) and distance-based sampling, to yield $M_{DEFT-UCS}$ that matches or exceeds the performance of the state-of-the-art CoEDIT while using only a fraction of the data. Across eight evaluation datasets covering six edit tasks, DEFT-UCS with as little as $32.5\%$ of $D_{CoEDIT}$ achieves competitive SARI and ROUGE-L scores and gains in human-perceived edit quality. The work demonstrates the practicality of unsupervised core-set-based data pruning for NLP tasks, discusses limitations of manually chosen hyperparameters, and points to future work on automatic parameter selection and broader task applicability.
Abstract
Recent advances have led to the availability of many pre-trained language models (PLMs); however, a question that remains is how much data is truly needed to fine-tune PLMs for downstream tasks? In this work, we introduce DEFT-UCS, a data-efficient fine-tuning framework that leverages unsupervised core-set selection to identify a smaller, representative dataset that reduces the amount of data needed to fine-tune PLMs for downstream tasks. We examine the efficacy of DEFT-UCS in the context of text-editing LMs, and compare to the state-of-the art text-editing model, CoEDIT. Our results demonstrate that DEFT-UCS models are just as accurate as CoEDIT, across eight different datasets consisting of six different editing tasks, while finetuned on 70% less data.
