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arXiv · 2311.17563

Efficient Computation of Sparse and Robust Maximum Association Estimators

Abstract

Robust statistical estimators offer resilience against outliers but are often computationally challenging, particularly in high-dimensional sparse settings. Modern optimization techniques are utilized for robust sparse association estimators without imposing constraints on the covariance structure. The approach splits the problem into a robust estimation phase, followed by optimization of a decoupled, biconvex problem to derive the sparse canonical vectors. An augmented Lagrangian algorithm, combined with a modified adaptive gradient descent method, induces sparsity through simultaneous updates of both canonical vectors. Results demonstrate improved precision over existing methods, with high-dimensional empirical examples illustrating the effectiveness of this approach. The methodology can also be extended to other robust sparse estimators.

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BibTeXRIS

Pia Pfeiffer, Andreas Alfons, Peter Filzmoser. 2023-11-29. Efficient Computation of Sparse and Robust Maximum Association Estimators. https://doi.org/10.1016/j.csda.2025.108133

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