Limitations of Information-Theoretic Generalization Bounds for Gradient Descent Methods in Stochastic Convex Optimization

  title={Limitations of Information-Theoretic Generalization Bounds for Gradient Descent Methods in Stochastic Convex Optimization},
  author={Mahdi Haghifam and Borja Rodr'iguez-G'alvez and Ragnar Thobaben and Mikael Skoglund and Daniel M. Roy and Gintare Karolina Dziugaite},
  booktitle={International Conference on Algorithmic Learning Theory},
To date, no"information-theoretic"frameworks for reasoning about generalization error have been shown to establish minimax rates for gradient descent in the setting of stochastic convex optimization. In this work, we consider the prospect of establishing such rates via several existing information-theoretic frameworks: input-output mutual information bounds, conditional mutual information bounds and variants, PAC-Bayes bounds, and recent conditional variants thereof. We prove that none of these… 

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