Abstract
We introduce and investigate stochastic processes designed to find local minimizers and saddle points of non-convex functions, exploring the landscape more efficiently than the standard noisy gradient descent. The processes switch between two behaviours, a noisy gradient descent and a noisy saddle point search. It is proven to be well-defined and to converge to a stationary distribution in the long time. Numerical experiments are provided on low-dimensional toy models and for Lennard–Jones clusters.
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This works is supported by the French ANR grant SWIDIMS (ANR-20-CE40-0022).
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LJ and PM wrote the manuscript, LJ wrote the code, and prepared the figures.
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Journel, L., Monmarché, P. Switched diffusion processes for non-convex optimization and saddle points search. Stat Comput 33, 139 (2023). https://doi.org/10.1007/s11222-023-10315-2
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DOI: https://doi.org/10.1007/s11222-023-10315-2