Large-Scale Data Selection for Instruction Tuning
Authors: name: Hamish Ivison; name: Muru Zhang; name: Faeze Brahman; name: Pang Wei Koh; name: Pradeep Dasigi
Published: 2025-03-03 18:37:26

Abstract: Selecting high-quality training data from a larger pool is a crucial step
when instruction-tuning language models, as carefully curated datasets often
produce models that outperform those trained on much larger, noisier datasets.
Automated data selection approaches for instruction-tuning are typically tested
by selecting small datasets (roughly 10k samples) from small pools (100-200k
samples). However, popular deployed instruction-tuned models often train on
hundreds of thousands to millions of samples, subsampled from even larger data
pools. We present a systematic study of how well data selection methods scale
to these settings, selecting up to 2.5M samples from pools of up to 5.8M
samples and evaluating across 7 diverse tasks. We show that many recently
proposed methods fall short of random selection in this setting (while using
more compute), and even decline in performance when given access to larger
pools of data to select over. However, we find that a variant of
representation-based data selection (RDS+), which uses weighted mean pooling of
pretrained LM hidden states, consistently outperforms more complex methods
across all settings tested -- all whilst being more compute-efficient. Our
findings highlight that the scaling properties of proposed automated selection
methods should be more closely examined. We release our code, data, and models
at https://github.com/hamishivi/automated-instruction-selection.