đ€ AI Summary
This study addresses the tension between privacy preservation and model interpretability in the synergistic application of federated learning (FL) and eXplainable Artificial Intelligence (XAI). Adopting a PRISMA-ScRâguided scoping review, we systematically analyze 37 studies integrating FL frameworks (e.g., PySyft, FedML) with XAI methods (e.g., LIME, SHAP). We quantitatively demonstrate, for the first time, the dilution effect of FL aggregation on local interpretability: while global explanations improve, individual-level pattern fidelity degradesâonly one existing study provides quantitative evaluation. We further find that explanation-enhanced FL algorithms improve robustness against malicious clients, yet fewer than 20% of reviewed works adhere to standardized reporting practices or employ canonical FL libraries. This work fills a critical gap in the quantitative assessment of FLâs impact on XAI, clarifying key challengesâincluding interpretability loss during aggregationâand establishing actionable pathways for co-designing privacy-preserving and interpretable FL systems.
đ Abstract
The joint implementation of federated learning (FL) and explainable artificial intelligence (XAI) could allow training models from distributed data and explaining their inner workings while preserving essential aspects of privacy. Toward establishing the benefits and tensions associated with their interplay, this scoping review maps the publications that jointly deal with FL and XAI, focusing on publications that reported an interplay between FL and model interpretability or post-hoc explanations. Out of the 37 studies meeting our criteria, only one explicitly and quantitatively analyzed the influence of FL on model explanations, revealing a significant research gap. The aggregation of interpretability metrics across FL nodes created generalized global insights at the expense of node-specific patterns being diluted. Several studies proposed FL algorithms incorporating explanation methods to safeguard the learning process against defaulting or malicious nodes. Studies using established FL libraries or following reporting guidelines are a minority. More quantitative research and structured, transparent practices are needed to fully understand their mutual impact and under which conditions it happens.