4 papers · 1 filter
On the Condition Number Dependency in Bilevel Optimization
Lesi Chen, Kaiyi Ji, Jingzhao Zhang
Bilevel optimization minimizes an objective function, defined by an upper-level problem whose feasible region is the solution of a lower-level problem. We study the oracle complexi…
Faster Gradient Methods for Highly-Smooth Stochastic Bilevel Optimization
Lesi Chen, Junru Li, El Mahdi Chayti +1
This paper studies the complexity of finding an -stationary point for stochastic bilevel optimization when the upper-level problem is nonconvex and the lower-level problem is st…
Solving Convex-Concave Problems with Second-Order Oracle Complexity
Lesi Chen, Chengchang Liu, Luo Luo +1
Previous algorithms can solve convex-concave minimax problems with second-order oracle calls usin…
Faster Newton Methods for Convex and Nonconvex Optimization in Gradient Complexity
Lesi Chen, Chengchang Liu, Luo Luo +1
Second-order optimization methods are computationally expensive for large-scale problems. Recently, Doikov, Chayti, and Jaggi (ICML 2023) proposed the LazyCRN method that reduces c…