# Newton-MR: Inexact Newton Method With Minimum Residual Sub-problem Solver

arXiv: https://arxiv.org/abs/1810.00303 · HTML: https://mlsanity.com/paper/1810.00303/

## Key facts

- Cited by 6 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 30 Sep 2018.

## Built on by (most cited first, 6 of 6)

- [SketchySGD: Reliable Stochastic Optimization via Randomized Curvature Estimates](https://mlsanity.com/paper/2211.08597/) (2022)
- [Constrained Optimization via Exact Augmented Lagrangian and Randomized Iterative Sketching](https://mlsanity.com/paper/2305.18379/) (2023)
- [SAPPHIRE: Preconditioned Stochastic Variance Reduction for Faster Large-Scale Statistical Learning](https://mlsanity.com/paper/2501.15941/) (2025)
- [A Natural Primal-Dual Hybrid Gradient Method for Adversarial Neural Network Training on Solving Partial Differential Equations](https://mlsanity.com/paper/2411.06278/) (2024)
- [First-ish Order Methods: Hessian-aware Scalings of Gradient Descent](https://mlsanity.com/paper/2502.03701/) (2025)
- [An Efficient Nonlinear Acceleration method that Exploits Symmetry of the Hessian](https://mlsanity.com/paper/2210.12573/) (2022)

## Abstract (arXiv)

We consider a variant of inexact Newton Method, called Newton-MR, in which the least-squares sub-problems are solved approximately using Minimum Residual method. By construction, Newton-MR can be readily applied for unconstrained optimization of a class of non-convex problems known as invex, which subsumes convexity as a sub-class. For invex optimization, instead of the classical Lipschitz continuity assumptions on gradient and Hessian, Newton-MR's global convergence can be guaranteed under a weaker notion of joint regularity of Hessian and gradient. We also obtain Newton-MR's problem-independent local convergence to the set of minima. We show that fast local/global convergence can be guaranteed under a novel inexactness condition, which, to our knowledge, is much weaker than the prior related works. Numerical results demonstrate the performance of Newton-MR as compared with several other Newton-type alternatives on a few machine learning problems.
