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Equation 20 · Part 2 · The Hardest Unsolved Problems in Small and On-Device AI

Symbol delta

(ε,δ)(\varepsilon,\delta)
δ\delta

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delta is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

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delta is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

The second is about whether differential privacy, as currently deployed in federated on-device fine-tuning, is an adequate defense or a partial one whose adequacy depends on an attacker’s sophistication. DP-FedLoRA’s authors present their calibrated-noise mechanism as delivering “strong privacy guarantees” alongside competitive model performance [ 7 ] . The Projection Residual attack was built and tested specifically to probe that class of claim, and its authors report their method holds up “even under strong differential privacy defenses” [ 6 ] . This is not necessarily a contradiction — a formal (ε\varepsilon,δ\delta) guarantee bounds a specific kind of information leakage under specific…

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