HyperbolicLR: Epoch insensitive learning rate scheduler
Tae-Geun Kim
TL;DR
This work tackles epoch sensitivity in learning rate scheduling by introducing HyperbolicLR and ExpHyperbolicLR, two schedulers anchored in hyperbolic curve properties to stabilize early learning-rate changes across different epoch counts $N$. The authors provide explicit formulations, analyze their theoretical properties, and compare them against common schedulers, including PolynomialLR and CosineAnnealingLR, using three diverse tasks: image classification on CIFAR-10, time-series forecasting with oscillations, and operator learning with DeepONet/TraONet. Through a two-stage experimental protocol involving hyperparameter optimization at 50 epochs and evaluation up to 200 epochs, the study demonstrates that HyperbolicLR and ExpHyperbolicLR exhibit superior learning-curve stability (low smoothed learning-curve differences) and stronger, more consistent performance gains (via power-regression metrics and $R^2$), particularly as training duration increases. The results suggest that hyperbolic-based schedulers offer robust, resource-efficient optimization, with ExpHyperbolicLR delivering especially stable behavior in settings prone to overfitting, while the authors acknowledge scenario-dependent scheduler choice and call for broader validation and theoretical development.
Abstract
This study proposes two novel learning rate schedulers -- Hyperbolic Learning Rate Scheduler (HyperbolicLR) and Exponential Hyperbolic Learning Rate Scheduler (ExpHyperbolicLR) -- to address the epoch sensitivity problem that often causes inconsistent learning curves in conventional methods. By leveraging the asymptotic behavior of hyperbolic curves, the proposed schedulers maintain more stable learning curves across varying epoch settings. Specifically, HyperbolicLR applies this property directly in the epoch-learning rate space, while ExpHyperbolicLR extends it to an exponential space. We first determine optimal hyperparameters for each scheduler on a small number of epochs, fix these hyperparameters, and then evaluate performance as the number of epochs increases. Experimental results on various deep learning tasks (e.g., image classification, time series forecasting, and operator learning) demonstrate that both HyperbolicLR and ExpHyperbolicLR achieve more consistent performance improvements than conventional schedulers as training duration grows. These findings suggest that our hyperbolic-based schedulers offer a more robust and efficient approach to deep network optimization, particularly in scenarios constrained by computational resources or time.
