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On the Differentially Private Nature of Perturbed Gradient Descent

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 نشر من قبل Thulasi Tholeti
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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We consider the problem of empirical risk minimization given a database, using the gradient descent algorithm. We note that the function to be optimized may be non-convex, consisting of saddle points which impede the convergence of the algorithm. A perturbed gradient descent algorithm is typically employed to escape these saddle points. We show that this algorithm, that perturbs the gradient, inherently preserves the privacy of the data. We then employ the differential privacy framework to quantify the privacy hence achieved. We also analyze the change in privacy with varying parameters such as problem dimension and the distance between the databases.



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