Multivariate time series forecasting focuses on predicting future values based on historical context. State-of-the-art sequence-to-sequence models rely on neural attention between timesteps, which allows for temporal learning but fails to consider distinct spatial relationships between variables. In contrast, methods based on graph neural networks explicitly model variable relationships. However, these methods often rely on predefined graphs that cannot change over time and perform separate spatial and temporal updates without establishing direct connections between each variable at every timestep. Our work addresses these problems by translating multivariate forecasting into a "spatiotemporal sequence" formulation where each Transformer input token represents the value of a single variable at a given time. Long-Range Transformers can then learn interactions between space, time, and value information jointly along this extended sequence. Our method, which we call Spacetimeformer, achieves competitive results on benchmarks from traffic forecasting to electricity demand and weather prediction while learning spatiotemporal relationships purely from data.
翻译:多元时间序列预测注重历史语境下的未来值预测。最先进的序列到序列模型依赖于时间步之间的神经注意力,这允许进行时间学习,但未能考虑不同变量之间的空间关系。相反,基于图神经网络的方法明确建模了变量之间的关系。但这些方法经常依赖于预定义的图表,在时间上不会变化,并且在不建立每个时间步骤中每个变量之间的直接联系的情况下进行分离的空间和时间更新。我们的工作通过将多元预测转化为“时空序列”表述,其中每个Transformer输入令牌表示给定时间的单个变量的值。随后,长距离Transformer可以沿着这个扩展序列联合学习空间、时间和价值信息之间的互动。我们的方法称为空时Transformer,在从交通预测到电力需求和天气预测的基准测试中实现了有竞争力的结果,同时纯粹从数据中学习时空关系。