Multifidelity Covariance Estimation via Regression on the Manifold of Symmetric Positive Definite Matrices

التفاصيل البيبلوغرافية
العنوان: Multifidelity Covariance Estimation via Regression on the Manifold of Symmetric Positive Definite Matrices
المؤلفون: Maurais, Aimee, Alsup, Terrence, Peherstorfer, Benjamin, Marzouk, Youssef
سنة النشر: 2023
المجموعة: Computer Science
Mathematics
Statistics
مصطلحات موضوعية: Statistics - Computation, Computer Science - Machine Learning, Mathematics - Numerical Analysis
الوصف: We introduce a multifidelity estimator of covariance matrices formulated as the solution to a regression problem on the manifold of symmetric positive definite matrices. The estimator is positive definite by construction, and the Mahalanobis distance minimized to obtain it possesses properties which enable practical computation. We show that our manifold regression multifidelity (MRMF) covariance estimator is a maximum likelihood estimator under a certain error model on manifold tangent space. More broadly, we show that our Riemannian regression framework encompasses existing multifidelity covariance estimators constructed from control variates. We demonstrate via numerical examples that our estimator can provide significant decreases, up to one order of magnitude, in squared estimation error relative to both single-fidelity and other multifidelity covariance estimators. Furthermore, preservation of positive definiteness ensures that our estimator is compatible with downstream tasks, such as data assimilation and metric learning, in which this property is essential.
Comment: 30 pages + 15-page supplement
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2307.12438
رقم الأكسشن: edsarx.2307.12438
قاعدة البيانات: arXiv