SONIA: A Symmetric Blockwise Truncated Optimization Algorithm
- URL: http://arxiv.org/abs/2006.03949v1
- Date: Sat, 6 Jun 2020 19:28:14 GMT
- Title: SONIA: A Symmetric Blockwise Truncated Optimization Algorithm
- Authors: Majid Jahani, Mohammadreza Nazari, Rachael Tappenden, Albert S.
Berahas, Martin Tak\'a\v{c}
- Abstract summary: This work presents a new algorithm for empirical risk.
The algorithm bridges the gap between first- and second-order search methods by computing a second-order search-type update in one subspace, coupled with a scaled steepest descent step in the Theoretical complement.
- Score: 2.9923891863939938
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: This work presents a new algorithm for empirical risk minimization. The
algorithm bridges the gap between first- and second-order methods by computing
a search direction that uses a second-order-type update in one subspace,
coupled with a scaled steepest descent step in the orthogonal complement. To
this end, partial curvature information is incorporated to help with
ill-conditioning, while simultaneously allowing the algorithm to scale to the
large problem dimensions often encountered in machine learning applications.
Theoretical results are presented to confirm that the algorithm converges to a
stationary point in both the strongly convex and nonconvex cases. A stochastic
variant of the algorithm is also presented, along with corresponding
theoretical guarantees. Numerical results confirm the strengths of the new
approach on standard machine learning problems.
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