On Numerical Integration in Neural Ordinary Differential Equations
- URL: http://arxiv.org/abs/2206.07335v1
- Date: Wed, 15 Jun 2022 07:39:01 GMT
- Title: On Numerical Integration in Neural Ordinary Differential Equations
- Authors: Aiqing Zhu, Pengzhan Jin, Beibei Zhu, Yifa Tang
- Abstract summary: We propose the inverse modified differential equations (IMDE) to clarify the influence of numerical integration on training Neural ODE models.
It is shown that training a Neural ODE model actually returns a close approximation of the IMDE, rather than the true ODE.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: The combination of ordinary differential equations and neural networks, i.e.,
neural ordinary differential equations (Neural ODE), has been widely studied
from various angles. However, deciphering the numerical integration in Neural
ODE is still an open challenge, as many researches demonstrated that numerical
integration significantly affects the performance of the model. In this paper,
we propose the inverse modified differential equations (IMDE) to clarify the
influence of numerical integration on training Neural ODE models. IMDE is
determined by the learning task and the employed ODE solver. It is shown that
training a Neural ODE model actually returns a close approximation of the IMDE,
rather than the true ODE. With the help of IMDE, we deduce that (i) the
discrepancy between the learned model and the true ODE is bounded by the sum of
discretization error and learning loss; (ii) Neural ODE using non-symplectic
numerical integration fail to learn conservation laws theoretically. Several
experiments are performed to numerically verify our theoretical analysis.
Related papers
- Neural Laplace for learning Stochastic Differential Equations [0.0]
Neuralplace is a unified framework for learning diverse classes of differential equations (DE)
For different classes of DE, this framework outperforms other approaches relying on neural networks that aim to learn classes of ordinary differential equations (ODE)
arXiv Detail & Related papers (2024-06-07T14:29:30Z) - Experimental study of Neural ODE training with adaptive solver for
dynamical systems modeling [72.84259710412293]
Some ODE solvers called adaptive can adapt their evaluation strategy depending on the complexity of the problem at hand.
This paper describes a simple set of experiments to show why adaptive solvers cannot be seamlessly leveraged as a black-box for dynamical systems modelling.
arXiv Detail & Related papers (2022-11-13T17:48:04Z) - Tunable Complexity Benchmarks for Evaluating Physics-Informed Neural
Networks on Coupled Ordinary Differential Equations [64.78260098263489]
In this work, we assess the ability of physics-informed neural networks (PINNs) to solve increasingly-complex coupled ordinary differential equations (ODEs)
We show that PINNs eventually fail to produce correct solutions to these benchmarks as their complexity increases.
We identify several reasons why this may be the case, including insufficient network capacity, poor conditioning of the ODEs, and high local curvature, as measured by the Laplacian of the PINN loss.
arXiv Detail & Related papers (2022-10-14T15:01:32Z) - Neural Laplace: Learning diverse classes of differential equations in
the Laplace domain [86.52703093858631]
We propose a unified framework for learning diverse classes of differential equations (DEs) including all the aforementioned ones.
Instead of modelling the dynamics in the time domain, we model it in the Laplace domain, where the history-dependencies and discontinuities in time can be represented as summations of complex exponentials.
In the experiments, Neural Laplace shows superior performance in modelling and extrapolating the trajectories of diverse classes of DEs.
arXiv Detail & Related papers (2022-06-10T02:14:59Z) - Learning ODEs via Diffeomorphisms for Fast and Robust Integration [40.52862415144424]
Differentiable solvers are central for learning Neural ODEs.
We propose an alternative approach to learning ODEs from data.
We observe improvements of up to two orders of magnitude when integrating learned ODEs with gradient.
arXiv Detail & Related papers (2021-07-04T14:32:16Z) - Incorporating NODE with Pre-trained Neural Differential Operator for
Learning Dynamics [73.77459272878025]
We propose to enhance the supervised signal in learning dynamics by pre-training a neural differential operator (NDO)
NDO is pre-trained on a class of symbolic functions, and it learns the mapping between the trajectory samples of these functions to their derivatives.
We provide theoretical guarantee on that the output of NDO can well approximate the ground truth derivatives by proper tuning the complexity of the library.
arXiv Detail & Related papers (2021-06-08T08:04:47Z) - A Probabilistic State Space Model for Joint Inference from Differential
Equations and Data [23.449725313605835]
We show a new class of solvers for ordinary differential equations (ODEs) that phrase the solution process directly in terms of Bayesian filtering.
It then becomes possible to perform approximate Bayesian inference on the latent force as well as the ODE solution in a single, linear complexity pass of an extended Kalman filter.
We demonstrate the expressiveness and performance of the algorithm by training a non-parametric SIRD model on data from the COVID-19 outbreak.
arXiv Detail & Related papers (2021-03-18T10:36:09Z) - Meta-Solver for Neural Ordinary Differential Equations [77.8918415523446]
We investigate how the variability in solvers' space can improve neural ODEs performance.
We show that the right choice of solver parameterization can significantly affect neural ODEs models in terms of robustness to adversarial attacks.
arXiv Detail & Related papers (2021-03-15T17:26:34Z) - ResNet After All? Neural ODEs and Their Numerical Solution [28.954378025052925]
We show that trained Neural Ordinary Differential Equation models actually depend on the specific numerical method used during training.
We propose a method that monitors the behavior of the ODE solver during training to adapt its step size.
arXiv Detail & Related papers (2020-07-30T11:24:05Z) - Stochasticity in Neural ODEs: An Empirical Study [68.8204255655161]
Regularization of neural networks (e.g. dropout) is a widespread technique in deep learning that allows for better generalization.
We show that data augmentation during the training improves the performance of both deterministic and versions of the same model.
However, the improvements obtained by the data augmentation completely eliminate the empirical regularization gains, making the performance of neural ODE and neural SDE negligible.
arXiv Detail & Related papers (2020-02-22T22:12:56Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.