FairSIN: Achieving Fairness in Graph Neural Networks through Sensitive Information Neutralization
Cheng Yang, Jixi Liu, Yunhe Yan, Chuan Shi
TL;DR
FairSIN addresses bias in graph neural networks by replacing standard filtering-based debiasing with a neutralization-based paradigm that injects Fairness-facilitating Features (F3) derived from heterogeneous neighbor information. The approach has both data-centric and model-centric variants, supported by a theoretical framework that uses a generative process and a leakage metric $\mathcal{H}(s|x)$ to show how message passing can amplify bias and how F3 mitigates it. Empirically, FairSIN improves fairness metrics such as Demographic Parity and Equal Opportunity across five real-world datasets and three GNN backbones while maintaining or enhancing predictive accuracy. The results demonstrate a scalable, task-irrelevant pre-processing option (FairSIN-F) and a cohesive model-aware strategy (FairSIN) with an adversarial component, offering a practical path toward fairer graph learning in diverse domains.
Abstract
Despite the remarkable success of graph neural networks (GNNs) in modeling graph-structured data, like other machine learning models, GNNs are also susceptible to making biased predictions based on sensitive attributes, such as race and gender. For fairness consideration, recent state-of-the-art (SOTA) methods propose to filter out sensitive information from inputs or representations, e.g., edge dropping or feature masking. However, we argue that such filtering-based strategies may also filter out some non-sensitive feature information, leading to a sub-optimal trade-off between predictive performance and fairness. To address this issue, we unveil an innovative neutralization-based paradigm, where additional Fairness-facilitating Features (F3) are incorporated into node features or representations before message passing. The F3 are expected to statistically neutralize the sensitive bias in node representations and provide additional nonsensitive information. We also provide theoretical explanations for our rationale, concluding that F3 can be realized by emphasizing the features of each node's heterogeneous neighbors (neighbors with different sensitive attributes). We name our method as FairSIN, and present three implementation variants from both data-centric and model-centric perspectives. Experimental results on five benchmark datasets with three different GNN backbones show that FairSIN significantly improves fairness metrics while maintaining high prediction accuracies.
