Sari la conținut

Română · beta. Traducerea a fost făcută automat și este încă în curs de revizuire. Citește pagina în engleză

perspectiva aiqbenchMachine learning

analiza aiqbench

This research identifies a novel "diffusion equilibrium" phase in neural network training where gradient alignment and residual homogeneity significantly enhance generalization, particularly within physics-informed networks. The authors propose a sample-wise re-weighting scheme to leverage this phase transition for faster convergence and improved performance in non-convex optimization landscapes. These findings offer concrete strategies for refining deep learning optimizers by targeting specific saturation-induced compression phenomena during activation.
Surse care acoperăarXiv, LessWrong
Ce este aceastaLectura unui model asupra articolului și a acoperirii conexe, scrisă pentru aiqbench. Nu sunt cuvintele publicației.

Learning in PINNs: Phase transition, diffusion equilibrium, and generalization

arXiv3 min de cititArticolul și perspectiva sunt în engleză.

arXiv:2403.18494v2 Announce Type: replace Abstract: We investigate the learning dynamics of fully-connected neural networks through the lens of the neural gradient signal-to-noise ratio (SNR), examining the behavior of first-order optimizers in non-convex objectives. Interpreting the drift/diffusion phases as proposed in the information bottleneck theory, we identify a third phase termed "diffusion equilibrium" (DE), a stable training phase characterized by highly-ordered neural gradients across the sample space. This phase is marked by an abrupt transition, where sample-wise gradients align (SNR increases), and stable optimizer convergence. Moreover, we find that when homogeneous residuals are also met across the sample space during the DE phase, this leads to better generalization, as the optimization steps are equally sensitive to each sample. Based on this observation, we propose a sample-wise re-weighting scheme, which considerably improves the residual homogeneity and generalization in quadratic loss functions, by targeting the problematic samples with large residuals and vanishing gradients. Finally, we explore the information compression phenomenon, pinpointing a significant saturation-induced compression of activations at the DE phase transition, driven by the sample-wise gradient directional alignment. Interestingly, it is during the saturation of activations that the model converges, with deeper layers experiencing negligible information loss. Supported by experimental examples on physics-informed neural networks (PINNs), which highlight the critical role of gradient agreement due to their inherent PDE-based interdependence of samples, our findings suggest that when both sample-wise gradients and residuals are ordered, this leads to faster convergence and better generalization. Identifying phase transitions could improve deep learning optimization strategies, enhancing physics-informed methods and machine learning performance.

Abstract:We investigate the learning dynamics of fully-connected neural networks through the lens of the neural gradient signal-to-noise ratio (SNR), examining the behavior of first-order optimizers in non-convex objectives. Interpreting the drift/diffusion phases as proposed in the information bottleneck theory, we identify a third phase termed "diffusion equilibrium" (DE), a stable training phase characterized by highly-ordered neural gradients across the sample space. This phase is marked by an abrupt transition, where sample-wise gradients align (SNR increases), and stable optimizer convergence. Moreover, we find that when homogeneous residuals are also met across the sample space during the DE phase, this leads to better generalization, as the optimization steps are equally sensitive to each sample. Based on this observation, we propose a sample-wise re-weighting scheme, which considerably improves the residual homogeneity and generalization in quadratic loss functions, by targeting the problematic samples with large residuals and vanishing gradients. Finally, we explore the information compression phenomenon, pinpointing a significant saturation-induced compression of activations at the DE phase transition, driven by the sample-wise gradient directional alignment. Interestingly, it is during the saturation of activations that the model converges, with deeper layers experiencing negligible information loss. Supported by experimental examples on physics-informed neural networks (PINNs), which highlight the critical role of gradient agreement due to their inherent PDE-based interdependence of samples, our findings suggest that when both sample-wise gradients and residuals are ordered, this leads to faster convergence and better generalization. Identifying phase transitions could improve deep learning optimization strategies, enhancing physics-informed methods and machine learning performance.

Machine Learning (cs.LG)

arXiv:2403.18494 [cs.LG]

(or arXiv:2403.18494v2 [cs.LG] for this version)

Anagnostopoulos, S.J., Toscano, J.D., Stergiopulos, N. and Karniadakis, G.E., 2025. Learning in pinns: Phase transition, diffusion equilibrium, and generalization. Neural Networks, p.107983

https://doi.org/10.1016/j.neunet.2025.107983 DOI(s) linking to related resources

Text integral sub licența deschisă a publicației · 290 cuvinte

Subiecte conexe