Loss Landscape of Shallow ReLU-like Neural Networks: Stationary Points, Saddle Escape, and Network Embedding
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Abstract (arXiv)
In this paper, we study the loss landscape of one-hidden-layer neural networks with ReLU-like activation functions trained with the empirical squared loss using gradient descent (GD). We identify the stationary points of such networks, which significantly slow down loss decrease during training. To capture such points while accounting for the non-differentiability of the loss, the stationary points that we study are directional stationary points, rather than other notions like Clarke stationary points. We show that, if a stationary point does not contain "escape neurons", which are defined with first-order conditions, it must be a local minimum. Moreover, for the scalar-output case, the presence of an escape neuron guarantees that the stationary point is not a local minimum. Our results refine the description of the saddle-to-saddle training process starting from infinitesimally small (vanishing) initialization for shallow ReLU-like networks: By precluding the saddle escape types that previous works did not rule out, we advance one step closer to a complete picture of the entire dynamics. Moreover, we are also able to fully discuss how network embedding, which is to instantiate a narrower network with a wider network, reshapes the stationary points.
Key facts. Cited by 6 papers in the map (data through 14 Oct 2026). Builds on 39 of its 51 references that are in the map. First posted on arXiv 8 Feb 2024.
Builds on
39 of 51 references.
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27 more
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Citing papers per year: 2025: 1; 2026: 5.
6 papers.
- 2025Saddle-to-Saddle Dynamics Explains A Simplicity Bias Across Neural Network Architecturescited by 15
- 2026From Approximation Rates to Loss-Landscape Barrier Decay in Shallow ReLU Networkscited by 0
- 2026A Theory of Saddle Escape in Deep Nonlinear Networkscited by 0
- 2026A Geometric Characterization of the Stationary Plateau for Two-Layer Neural Networkscited by 0
- 2026Effects of width-dependent model hyperparameters and ℓ2-regularization on the loss landscape of two-layer ReLU networkscited by 0
- 2026Removing spurious minima for planar features by skip connectionscited by 0
- 2026Removing spurious minima for planar features by skip connections1 Oct 2026
- 2026Effects of width-dependent model hyperparameters and ℓ2-regularization on the loss landscape of two-layer ReLU networks18 Jul 2026
- 2026A Geometric Characterization of the Stationary Plateau for Two-Layer Neural Networks3 Jun 2026
- 2026A Theory of Saddle Escape in Deep Nonlinear Networks2 May 2026
- 2026From Approximation Rates to Loss-Landscape Barrier Decay in Shallow ReLU Networks19 Feb 2026
- 2025Saddle-to-Saddle Dynamics Explains A Simplicity Bias Across Neural Network Architectures23 Dec 2025