🤖 AI Summary
Traditional integer-order and constant-order fractional differential equations struggle to capture dynamic memory evolution. To address this, we propose Neural Variable-Order Fractional Differential Equation Networks (NvoFDE). Our method introduces a learnable, hidden-state-dependent variable-order Caputo fractional derivative into the neural differential equation framework—enabling the differentiation order to adapt dynamically to evolving hidden features and explicitly modeling non-stationary long-range dependencies. NvoFDE integrates an implicit neural ODE solver with graph neural networks, supporting end-to-end training. Extensive experiments on diverse graph learning tasks demonstrate that NvoFDE consistently outperforms both integer-order and constant-order fractional baselines, achieving significant gains in memory modeling fidelity and generalization performance. This work establishes a more expressive fractional-order neural dynamical paradigm for modeling complex dynamic systems.
📝 Abstract
Neural differential equation models have garnered significant attention in recent years for their effectiveness in machine learning applications.Among these, fractional differential equations (FDEs) have emerged as a promising tool due to their ability to capture memory-dependent dynamics, which are often challenging to model with traditional integer-order approaches.While existing models have primarily focused on constant-order fractional derivatives, variable-order fractional operators offer a more flexible and expressive framework for modeling complex memory patterns. In this work, we introduce the Neural Variable-Order Fractional Differential Equation network (NvoFDE), a novel neural network framework that integrates variable-order fractional derivatives with learnable neural networks.Our framework allows for the modeling of adaptive derivative orders dependent on hidden features, capturing more complex feature-updating dynamics and providing enhanced flexibility. We conduct extensive experiments across multiple graph datasets to validate the effectiveness of our approach.Our results demonstrate that NvoFDE outperforms traditional constant-order fractional and integer models across a range of tasks, showcasing its superior adaptability and performance.