  Data attribution seeks to trace model outputs back to training data. With the
recent development of diffusion models, data attribution has become a desired
module to properly assign valuations for high-quality or copyrighted training
samples, ensuring that data contributors are fairly compensated or credited.
Several theoretically motivated methods have been proposed to implement data
attribution, in an effort to improve the trade-off between computational
scalability and effectiveness. In this work, we conduct extensive experiments
and ablation studies on attributing diffusion models, specifically focusing on
DDPMs trained on CIFAR-10 and CelebA, as well as a Stable Diffusion model
LoRA-finetuned on ArtBench. Intriguingly, we report counter-intuitive
observations that theoretically unjustified design choices for attribution
empirically outperform previous baselines by a large margin, in terms of both
linear datamodeling score and counterfactual evaluation. Our work presents a
significantly more efficient approach for attributing diffusion models, while
the unexpected findings suggest that at least in non-convex settings,
constructions guided by theoretical assumptions may lead to inferior
attribution performance. The code is available at
https://github.com/sail-sg/D-TRAK.
