Fed-RD: Privacy-Preserving Federated Learning for Financial Crime Detection
Md. Saikat Islam Khan, Aparna Gupta, Oshani Seneviratne, Stacy Patterson
TL;DR
Fed-RD tackles end-to-end privacy in federated learning for relational financial data partitioned both vertically and horizontally.It introduces two fusion approaches: Approach 1 uses Local Rényi differential privacy with Gaussian noise on embeddings, while Approach 2 uses PBM and MPC to compute a private embedding sum; both yield formal $(\alpha, \epsilon)$-RDP guarantees over $Q$ iterations.The method models data with three components—a transaction model with parameters $\boldsymbol{\theta}_T$, an account model with parameters $\boldsymbol{\theta}_B$, and a fusion model with parameters $\boldsymbol{\theta}_F$—and optimizes the loss $\mathcal{L}(\boldsymbol{\\Theta}; \mathcal{X}_T, \mathcal{X}_B, \mathbf{y})$.Experiments on SWIFT-like and AMLSim synthetic datasets show that privacy-preserving Fed-RD attains high predictive performance while maintaining formal privacy guarantees and outperforming a baseline XGBoost model on transaction features.
Abstract
We introduce Federated Learning for Relational Data (Fed-RD), a novel privacy-preserving federated learning algorithm specifically developed for financial transaction datasets partitioned vertically and horizontally across parties. Fed-RD strategically employs differential privacy and secure multiparty computation to guarantee the privacy of training data. We provide theoretical analysis of the end-to-end privacy of the training algorithm and present experimental results on realistic synthetic datasets. Our results demonstrate that Fed-RD achieves high model accuracy with minimal degradation as privacy increases, while consistently surpassing benchmark results.
