Test Time Learning for Time Series Forecasting
Panayiotis Christou, Shichu Chen, Xupeng Chen, Parijat Dube
TL;DR
The paper tackles long-term time series forecasting (LTSF) under non-stationarity and long-range dependencies, where Transformer-based methods are costly and state-space models have limitations. It introduces Test-Time Training (TTT) modules embedded in a TimeMachine backbone, featuring a two-level hierarchical embedding, convolutional context submodules, and two modes of channel processing to enable dynamic adaptation with linear sequence-length complexity. Across seven benchmark datasets, TimeMachine-TTT variants outperform state-of-the-art models, particularly on longer horizons and larger datasets, with Conv Stack 5 often delivering the strongest results. The work also presents extensive ablations, longer sequence/prediction-length experiments, and complexity analyses, positioning TTT as a scalable and effective direction for high-performance LTSF and offering a foundation for future architectural exploration.
Abstract
Time-series forecasting has seen significant advancements with the introduction of token prediction mechanisms such as multi-head attention. However, these methods often struggle to achieve the same performance as in language modeling, primarily due to the quadratic computational cost and the complexity of capturing long-range dependencies in time-series data. State-space models (SSMs), such as Mamba, have shown promise in addressing these challenges by offering efficient solutions with linear RNNs capable of modeling long sequences with larger context windows. However, there remains room for improvement in accuracy and scalability. We propose the use of Test-Time Training (TTT) modules in a parallel architecture to enhance performance in long-term time series forecasting. Through extensive experiments on standard benchmark datasets, we demonstrate that TTT modules consistently outperform state-of-the-art models, including the Mamba-based TimeMachine, particularly in scenarios involving extended sequence and prediction lengths. Our results show significant improvements in Mean Squared Error (MSE) and Mean Absolute Error (MAE), especially on larger datasets such as Electricity, Traffic, and Weather, underscoring the effectiveness of TTT in capturing long-range dependencies. Additionally, we explore various convolutional architectures within the TTT framework, showing that even simple configurations like 1D convolution with small filters can achieve competitive results. This work sets a new benchmark for time-series forecasting and lays the groundwork for future research in scalable, high-performance forecasting models.
