EMAformer: Enhancing Transformer Through Embedding Armor for Time Series Forecasting

Abstract Multivariate time series forecasting is crucial across a wide range of domains. While presenting notable progress for the Transformer architecture, iTransformer still lags behind the latest MLP-based models. We attribute this performance gap to unstable inter-channel relationships. To bridge this gap, we propose EMAformer, a simple yet effective model that enhances the Transformer with an auxiliary embedding suite, akin to armor that reinforces its ability. By introducing three key inductive biases, i.e., global stability, phase sensitivity, and cross-axis specificity, EMAformer unlocks the further potential of the Transformer architecture, achieving state-of-the-art performance on 12 real-world benchmarks and reducing forecasting errors by an average of 2.73% in MSE and 5.15% in MAE. This significantly advances the practical applicability of Transformer-based approaches for multivariate time series forecasting.