Robust Semiparametric Efficient Estimators in Complex Elliptically Symmetric Distributions

Autor: Alexandre Renaux, Frédéric Pascal, Stefano Fortunati
Přispěvatelé: Laboratoire des signaux et systèmes (L2S), CentraleSupélec-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ANR-17-ASTR-0015,MARGARITA,Nouvelles Techniques Robustes et d'Inférences pour le Radar Adaptatif Moderne(2017)
Rok vydání: 2020
Předmět:
Zdroj: IEEE Transactions on Signal Processing
IEEE Transactions on Signal Processing, Institute of Electrical and Electronics Engineers, 2020, 68, pp.5003-5015. ⟨10.1109/TSP.2020.3019110⟩
ISSN: 1941-0476
1053-587X
DOI: 10.1109/tsp.2020.3019110
Popis: International audience; Covariance matrices play a major role in statistics , signal processing and machine learning applications. This paper focuses on the semiparametric covariance/scatter matrix estimation problem in elliptical distributions. The class of elliptical distributions can be seen as a semiparametric model where the finite-dimensional vector of interest is given by the location vector and by the (vectorized) covariance/scatter matrix, while the density generator represents an infinite-dimensional nuisance function. The main aim of this work is then to provide possible estimators of the finite-dimensional parameter vector able to reconcile the two dichotomic concepts of robustness and (semiparametric) efficiency. An R-estimator satisfying these requirements has been recently proposed by Hallin, Oja and Paindaveine for real-valued elliptical data by exploiting the Le Cam's theory of one-step efficient estimators and the rank-based statistics. In this paper, we firstly recall the building blocks underlying the derivation of such real-valued R-estimator, then its extension to complex-valued data is proposed. Moreover, through numerical simulations, its estimation performance and robustness to outliers are investigated in a finite-sample regime.
Databáze: OpenAIRE