Irregular sampling intervals and missing values in real-world time series data present challenges for conventional methods that assume consistent intervals and complete data. Neural Ordinary Differential Equations (Neural ODEs) offer an alternative approach, utilizing neural networks combined with ODE solvers to learn continuous latent representations through parameterized vector fields. Neural Stochastic Differential Equations (Neural SDEs) extend Neural ODEs by incorporating a diffusion term, although this addition is not trivial, particularly when addressing irregular intervals and missing values. Consequently, careful design of drift and diffusion functions is crucial for maintaining stability and enhancing performance, while incautious choices can result in adverse properties such as the absence of strong solutions, stochastic destabilization, or unstable Euler discretizations, significantly affecting Neural SDEs' performance. In this study, we propose three stable classes of Neural SDEs: Langevin-type SDE, Linear Noise SDE, and Geometric SDE. Then, we rigorously demonstrate their robustness in maintaining excellent performance under distribution shift, while effectively preventing overfitting. To assess the effectiveness of our approach, we conduct extensive experiments on four benchmark datasets for interpolation, forecasting, and classification tasks, and analyze the robustness of our methods with 30 public datasets under different missing rates. Our results demonstrate the efficacy of the proposed method in handling real-world irregular time series data.

在处理真实世界的不规则时间序列数据中，由于不连续的采样间隔和缺失值，神经随机微分方程（Neural SDEs）的良好性能依赖于漂移和扩散函数的巧妙选择，本研究通过提出三个稳定的Neural SDE类别： Langevin型SDE、线性噪声SDE和几何SDE，并通过广泛的实验验证了这些方法在分布转移和不同缺失率下的鲁棒性，展示了该方法在处理真实世界不规则时间序列数据中的有效性。

分析非规则时间序列数据的稳定神经随机微分方程