A Full Characterization of Excess Risk via Empirical Risk Landscape
- URL: http://arxiv.org/abs/2012.02456v2
- Date: Fri, 29 Jan 2021 11:35:16 GMT
- Title: A Full Characterization of Excess Risk via Empirical Risk Landscape
- Authors: Mingyang Yi, Ruoyu Wang, Zhi-Ming Ma
- Abstract summary: In this paper, we provide a unified analysis of the risk of the model trained by a proper algorithm with both smooth convex and non- loss functions.
- Score: 8.797852602680445
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: In this paper, we provide a unified analysis of the excess risk of the model
trained by a proper algorithm with both smooth convex and non-convex loss
functions. In contrast to the existing bounds in the literature that depends on
iteration steps, our bounds to the excess risk do not diverge with the number
of iterations. This underscores that, at least for smooth loss functions, the
excess risk can be guaranteed after training. To get the bounds to excess risk,
we develop a technique based on algorithmic stability and non-asymptotic
characterization of the empirical risk landscape. The model obtained by a
proper algorithm is proved to generalize with this technique. Specifically, for
non-convex loss, the conclusion is obtained via the technique and analyzing the
stability of a constructed auxiliary algorithm. Combining this with some
properties of the empirical risk landscape, we derive converged upper bounds to
the excess risk in both convex and non-convex regime with the help of some
classical optimization results.
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