Dissecting and Mitigating Diffusion Bias via Mechanistic Interpretability
Journal:
arXiv
Published Date:
Mar 26, 2025
Abstract
Diffusion models have demonstrated impressive capabilities in synthesizing
diverse content. However, despite their high-quality outputs, these models
often perpetuate social biases, including those related to gender and race.
These biases can potentially contribute to harmful real-world consequences,
reinforcing stereotypes and exacerbating inequalities in various social
contexts. While existing research on diffusion bias mitigation has
predominantly focused on guiding content generation, it often neglects the
intrinsic mechanisms within diffusion models that causally drive biased
outputs. In this paper, we investigate the internal processes of diffusion
models, identifying specific decision-making mechanisms, termed bias features,
embedded within the model architecture. By directly manipulating these
features, our method precisely isolates and adjusts the elements responsible
for bias generation, permitting granular control over the bias levels in the
generated content. Through experiments on both unconditional and conditional
diffusion models across various social bias attributes, we demonstrate our
method's efficacy in managing generation distribution while preserving image
quality. We also dissect the discovered model mechanism, revealing different
intrinsic features controlling fine-grained aspects of generation, boosting
further research on mechanistic interpretability of diffusion models.