| International Journal of Computer Applications |
| Foundation of Computer Science (FCS), NY, USA |
| Volume 187 - Number 54 |
| Year of Publication: 2025 |
| Authors: Alexander Stotsky |
10.5120/ijca2025925940
|
Alexander Stotsky . Accelerating with Low Rank Updates: RLS Framework for Segmentation of the Forgetting Profile. International Journal of Computer Applications. 187, 54 ( Nov 2025), 1-5. DOI=10.5120/ijca2025925940
This paper introduces a novel regularization method that leverages segmentation of the forgetting profile for more robust modeling of data aging in sliding window least squares estimation. Each segment is designed to enforce specific desirable properties of the estimator such as rapidity, desired condition number of the information matrix, accuracy, numerical stability, etc. The forgetting profile is structured in three segments, where the first segment enables rapid estimation via fast exponential forgetting of recent data. The second segment features a decline in the profile and marks the transition to the third segment, which is characterized by slow exponential forgetting aimed at reducing the condition number of the information matrix using earlier measurements within the moving window. Condition number reduction mitigates error propagation, thereby enhancing accuracy and stability. This approach facilitates the incorporation of a priori information regarding signal characteristics (i.e., the expected behavior of the signal) into the estimator. The main contribution of this paper is the framework for development of a new family of recursive, computationally efficient algorithms with low rank updates, based on a novel matrix inversion lemma for moving windows and tailored to this regularization approach. New algorithms significantly improve the approximation accuracy of low resolution daily temperature measurements obtained at the Stockholm Old Astronomical Observatory, thereby enhancing the reliability of temperature predictions.