Equation 19 · Part 1 · The Hardest Unsolved Problems in Small and On-Device AI
Symbol varepsilon
What this part means
varepsilon is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Its job in the formula
varepsilon is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol varepsilon→Article meaning
The passage around this formula
Federated learning is the other common route to personalization without centralizing raw data: many devices train locally and only their model updates, not their data, are sent to a coordinating server for aggregation. DP-FedLoRA, a 2025 framework for privacy-enhanced federated fine-tuning of on-device LLMs, is explicit that this still needs its own safeguard, because federated fine-tuning on edge devices involves “processing sensitive, user-specific data, raising significant privacy concerns within the federated learning framework” even though raw data stays local [ 7 ] . Its response is differential privacy: each client “locally clips and perturbs its LoRA matrices using Gaussian noise”…
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Sources cited in the surrounding passage
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