An Empirical Evaluation of Federated Contextual Bandit Algorithms
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Abstract
As the adoption of federated learning increases for learning from sensitive data local to user devices, it is natural to ask if the learning can be done using implicit signals generated as users interact with the applications of interest, rather than requiring access to explicit labels which can be difficult to acquire in many tasks. We approach such problems with the framework of federated contextual bandits, and develop variants of prominent contextual bandit algorithms from the centralized seting for the federated setting. We carefully evaluate these algorithms in a range of scenarios simulated using publicly available datasets. Our simulations model typical setups encountered in the real-world, such as various misalignments between an initial pre-trained model and the subsequent user interactions due to non-stationarity in the data and/or heterogeneity across clients. Our experiments reveal the surprising effectiveness of the simple and commonly used softmax heuristic in balancing the well-know exploration-exploitation tradeoff across the breadth of our settings.Keywords
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This publication has 4 references indexed in Scilit:
- How to DP-fy ML: A Practical Guide to Machine Learning with Differential PrivacyJournal of Artificial Intelligence Research, 2023
- Learning to Generate Image Embeddings with User-Level Differential Privacy2023
- Federated learning and privacyCommunications of the ACM, 2022
- Doubly Robust Policy Evaluation and OptimizationStatistical Science, 2014