Privacy-Preserving Data Selection for Horizontal and Vertical Federated Learning

Federated learning (FL) enables distributed participants to collaboratively train a machine learning model without accessing to their local data. In FL systems, the selection of training samples has a significant impact on model performances, e.g., selecting participants whose datasets have low-quality samples, features would result in low accuracy, unstable models. In this work, we aim to solve the problem that selects a collection of high-quality training samples for a given FL task under a monetary budget. We propose a holistic design to efficiently select high-quality samples while preserve the privacy of participants’ local data, the server’s label set. We propose an efficient hierarchical sample selection mechanism to select relevant clients, their samples before training for horizontal federated learning (HFL). It uses the determinantal point process (DPP) to select both the statistical homogenous, content diverse clients, samples. Besides, we propose a private set intersection (PSI) based scheme to filter relevant features for the target VFL task. Finally, during training, an erroneous-aware importance based selection is proposed to dynamically select important clients, samples to accelerate model convergence. We verify the merits of our proposed solution with extensive experiments on a real AIoT system with 50 clients. The experimental results validate that our solution achieves accurate, efficient selection of high-quality data, consequently an FL model with a faster convergence speed, higher accuracy.