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Viewing neural network models in terms of their loss landscapes has a long history in the statistical mechanics approach to learning, and in recent years it has received attention within machine learning proper. Among other things, local metrics (such as the smoothness of the loss landscape) have been shown to correlate with global properties of the model (such as good generalization performance). Here, we perform a detailed empirical analysis of the loss landscape structure of thousands of neural network models, systematically varying learning tasks, model architectures, and/or quantity/quality of data. By considering a range of metrics that attempt to capture different aspects of the loss landscape, we demonstrate that the best test accuracy is obtained when: the loss landscape is globally well-connected; ensembles of trained models are more similar to each other; and models converge to locally smooth regions. We also show that globally poorly-connected landscapes can arise when models are small or when they are trained to lower quality data; and that, if the loss landscape is globally poorly-connected, then training to zero loss can actually lead to worse test accuracy. Our detailed empirical results shed light on phases of learning (and consequent double descent behavior), fundamental versus incidental determinants of good generalization, the role of load-like and temperature-like parameters in the learning process, different influences on the loss landscape from model and data, and the relationships between local and global metrics, all topics of recent interest.
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This content will become publicly available on March 24, 2026
MoXCo: How I learned to stop exploring and love my local minima?
Deep neural networks are well-known for their generalization capabilities, largely attributed to optimizers’ ability to find "good" solutions in high-dimensional loss landscapes. This work aims to deepen the understanding of optimization specifically through the lens of loss landscapes. We propose a generalized framework for adaptive optimization that favors convergence to these "good" solutions. Our approach shifts the optimization paradigm from merely finding solutions quickly to discovering solutions that generalize well, establishing a careful balance between optimization efficiency and model generalization. We empirically validate our claims using two-layer, fully connected neural network with ReLU activation and demonstrate practical applicability through binary quantization of ResNets. Our numerical results demonstrate that these adaptive optimizers facilitate exploration leading to faster convergence speeds and narrow the generalization gap between stochastic gradient descent and other adaptive methods.
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- PAR ID:
- 10649006
- Publisher / Repository:
- Proceedings of the Conference on Parsimony and Learning. (CPAL 2025)
- Date Published:
- Journal Name:
- Proceedings of Machine Learning Research
- ISSN:
- 2640-3498
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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