Orchestra: Unsupervised Federated Learning via Globally Consistent Clustering

Ekdeep Lubana, Chi Ian Tang, Fahim Kawsar, Robert Dick, Akhil Mathur
Proceedings of the 39th International Conference on Machine Learning, PMLR 162:14461-14484, 2022.

Abstract

Federated learning is generally used in tasks where labels are readily available (e.g., next word prediction). Relaxing this constraint requires design of unsupervised learning techniques that can support desirable properties for federated training: robustness to statistical/systems heterogeneity, scalability with number of participants, and communication efficiency. Prior work on this topic has focused on directly extending centralized self-supervised learning techniques, which are not designed to have the properties listed above. To address this situation, we propose Orchestra, a novel unsupervised federated learning technique that exploits the federation’s hierarchy to orchestrate a distributed clustering task and enforce a globally consistent partitioning of clients’ data into discriminable clusters. We show the algorithmic pipeline in Orchestra guarantees good generalization performance under a linear probe, allowing it to outperform alternative techniques in a broad range of conditions, including variation in heterogeneity, number of clients, participation ratio, and local epochs.

Cite this Paper


BibTeX
@InProceedings{pmlr-v162-lubana22a, title = {Orchestra: Unsupervised Federated Learning via Globally Consistent Clustering}, author = {Lubana, Ekdeep and Tang, Chi Ian and Kawsar, Fahim and Dick, Robert and Mathur, Akhil}, booktitle = {Proceedings of the 39th International Conference on Machine Learning}, pages = {14461--14484}, year = {2022}, editor = {Chaudhuri, Kamalika and Jegelka, Stefanie and Song, Le and Szepesvari, Csaba and Niu, Gang and Sabato, Sivan}, volume = {162}, series = {Proceedings of Machine Learning Research}, month = {17--23 Jul}, publisher = {PMLR}, pdf = {https://proceedings.mlr.press/v162/lubana22a/lubana22a.pdf}, url = {https://proceedings.mlr.press/v162/lubana22a.html}, abstract = {Federated learning is generally used in tasks where labels are readily available (e.g., next word prediction). Relaxing this constraint requires design of unsupervised learning techniques that can support desirable properties for federated training: robustness to statistical/systems heterogeneity, scalability with number of participants, and communication efficiency. Prior work on this topic has focused on directly extending centralized self-supervised learning techniques, which are not designed to have the properties listed above. To address this situation, we propose Orchestra, a novel unsupervised federated learning technique that exploits the federation’s hierarchy to orchestrate a distributed clustering task and enforce a globally consistent partitioning of clients’ data into discriminable clusters. We show the algorithmic pipeline in Orchestra guarantees good generalization performance under a linear probe, allowing it to outperform alternative techniques in a broad range of conditions, including variation in heterogeneity, number of clients, participation ratio, and local epochs.} }
Endnote
%0 Conference Paper %T Orchestra: Unsupervised Federated Learning via Globally Consistent Clustering %A Ekdeep Lubana %A Chi Ian Tang %A Fahim Kawsar %A Robert Dick %A Akhil Mathur %B Proceedings of the 39th International Conference on Machine Learning %C Proceedings of Machine Learning Research %D 2022 %E Kamalika Chaudhuri %E Stefanie Jegelka %E Le Song %E Csaba Szepesvari %E Gang Niu %E Sivan Sabato %F pmlr-v162-lubana22a %I PMLR %P 14461--14484 %U https://proceedings.mlr.press/v162/lubana22a.html %V 162 %X Federated learning is generally used in tasks where labels are readily available (e.g., next word prediction). Relaxing this constraint requires design of unsupervised learning techniques that can support desirable properties for federated training: robustness to statistical/systems heterogeneity, scalability with number of participants, and communication efficiency. Prior work on this topic has focused on directly extending centralized self-supervised learning techniques, which are not designed to have the properties listed above. To address this situation, we propose Orchestra, a novel unsupervised federated learning technique that exploits the federation’s hierarchy to orchestrate a distributed clustering task and enforce a globally consistent partitioning of clients’ data into discriminable clusters. We show the algorithmic pipeline in Orchestra guarantees good generalization performance under a linear probe, allowing it to outperform alternative techniques in a broad range of conditions, including variation in heterogeneity, number of clients, participation ratio, and local epochs.
APA
Lubana, E., Tang, C.I., Kawsar, F., Dick, R. & Mathur, A.. (2022). Orchestra: Unsupervised Federated Learning via Globally Consistent Clustering. Proceedings of the 39th International Conference on Machine Learning, in Proceedings of Machine Learning Research 162:14461-14484 Available from https://proceedings.mlr.press/v162/lubana22a.html.

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