Hello everyone, I've noticed that many participants are using decision tree-based models. I'm wondering how federated learning could be implemented with them, since—unlike neural networks—decision trees don't rely on weights that can be averaged across clients. It seems to present a lot of challenges, especially when it comes to synchronizing tree structures or securely evaluating splits. Could someone clarify this for me? Am I missing something?
Hi,
You're right with the challenges of using tree models for federation learning. In my chat with Copilot, although it noted the concern you raised, it suggested using a form of aggregation to aggregate client's predictions. It could be using the average of their probabilities or using a hard voting method by assigning class to the most frequent, if an odd number of clients is used.