污污草莓视频

Title: High-dimensional limit of streaming SGD for generalized linear models

Abstract: We provide a characterization of the high dimensional limit of one-pass, single batch stochastic gradient descent (SGD) in the case where the number of samples scales proportionally with the problem dimension. We characterize the limiting process in terms of its convergence to a high-dimensional stochastic differential equation, referred to as the homogenized SGD. Our proofs assume Gaussian data but allow for a very general covariance structure. Our set-up covers a range of optimization problems including linear regression, logistic regression, and some simple neural nets. For each of these models, the convergence of SGD to homogenized SGD enables us to derive a close approximation of the statistical risk (with explicit and vanishing error bounds) as the solution to a Volterra integral equation. I will also discuss the implications of our theorem in terms of SGD step-size and optimality conditions for descent. (Based on joint work with C. Paquette, E. Paquette, I. Seroussi).

References: The talk is mostly based on this preprint: . The special case of linear regression (without Gaussian assumption) is studied in this preprint: .