U-Mixer: An Unet-Mixer Architecture with Stationarity Correction for Time Series Forecasting
This addresses forecasting accuracy issues in domains like finance or weather, but appears incremental as it builds on existing architectures like Unet and Mixer.
The paper tackled the challenge of non-stationarity in time series forecasting by proposing U-Mixer, a framework combining Unet and Mixer with a stationarity correction method, achieving 14.5% and 7.7% improvements over state-of-the-art methods.
Time series forecasting is a crucial task in various domains. Caused by factors such as trends, seasonality, or irregular fluctuations, time series often exhibits non-stationary. It obstructs stable feature propagation through deep layers, disrupts feature distributions, and complicates learning data distribution changes. As a result, many existing models struggle to capture the underlying patterns, leading to degraded forecasting performance. In this study, we tackle the challenge of non-stationarity in time series forecasting with our proposed framework called U-Mixer. By combining Unet and Mixer, U-Mixer effectively captures local temporal dependencies between different patches and channels separately to avoid the influence of distribution variations among channels, and merge low- and high-levels features to obtain comprehensive data representations. The key contribution is a novel stationarity correction method, explicitly restoring data distribution by constraining the difference in stationarity between the data before and after model processing to restore the non-stationarity information, while ensuring the temporal dependencies are preserved. Through extensive experiments on various real-world time series datasets, U-Mixer demonstrates its effectiveness and robustness, and achieves 14.5\% and 7.7\% improvements over state-of-the-art (SOTA) methods.