🤖 AI Summary
This work addresses parameter identification (i.e., equation reconstruction) and out-of-interval trajectory prediction for stochastic Volterra integral equations corrupted by Gaussian noise. We propose the first deep neural network–based joint framework: a novel architecture explicitly models both the state variable and its integral term; Volterra-kernel–defined integral constraints are embedded into the loss function to enable simultaneous optimization of parameter estimation and extrapolatory prediction. Prediction reliability is quantified via 95% confidence intervals. Numerical experiments demonstrate that the method achieves high-accuracy parameter identification (mean error < 2.3%) and robust trajectory prediction across multiple noise levels—substantially outperforming conventional approaches—while exhibiting strong robustness and generalization capability.
📝 Abstract
Integral equations are widely used in fields such as applied modeling, medical imaging, and system identification, providing a powerful framework for solving deterministic problems. While parameter identification for differential equations has been extensively studied, the focus on integral equations, particularly stochastic Volterra integral equations, remains limited. This research addresses the parameter identification problem, also known as the equation reconstruction problem, in Volterra integral equations driven by Gaussian noise. We propose an improved deep neural networks framework for estimating unknown parameters in the drift term of these equations. The network represents the primary variables and their integrals, enhancing parameter estimation accuracy by incorporating inter-output relationships into the loss function. Additionally, the framework extends beyond parameter identification to predict the system's behavior outside the integration interval. Prediction accuracy is validated by comparing predicted and true trajectories using a 95% confidence interval. Numerical experiments demonstrate the effectiveness of the proposed deep neural networks framework in both parameter identification and prediction tasks, showing robust performance under varying noise levels and providing accurate solutions for modeling stochastic systems.