Results 11 to 20 of about 3,804 (260)

Shrinkage estimators of large covariance matrices with Toeplitz targets in array signal processing. [PDF]

open access: yesSci Rep, 2022
The problem of estimating a large covariance matrix arises in various statistical applications. This paper develops new covariance matrix estimators based on shrinkage regularization.
Zhang B, Yuan S.
europepmc   +2 more sources

A Class of Shrinkage Estimators

open access: yesJournal of the Royal Statistical Society Series B: Statistical Methodology, 1978
Summary In this paper we define a class of shrinkage estimators, all of whose members have a mean square error matrix which is less than that of the ordinary least squares estimator by a positive semidefinite matrix if (β-b  *)T  X  T  X (β-b  *) ≤ σ2.
R W Farebrother
exaly   +3 more sources

A study of minimax shrinkage estimators dominating the James-Stein estimator under the balanced loss function

open access: yesOpen Mathematics, 2022
One of the most common challenges in multivariate statistical analysis is estimating the mean parameters. A well-known approach of estimating the mean parameters is the maximum likelihood estimator (MLE).
Abdelkader Benkhaled   +2 more
exaly   +2 more sources

Improved Shrinkage Estimators of Covariance Matrices With Toeplitz-Structured Targets in Small Sample Scenarios

open access: yesIEEE Access, 2019
Shrinkage regularization is an effective strategy to estimate the covariance matrix of multi-variate random vector in small sample scenarios. The purpose of this paper is to propose improved linear shrinkage estimators of covariance matrix as two types ...
Bin Zhang, Jianbo Li
exaly   +3 more sources

Enhancing accuracy in modelling highly multicollinear data using alternative shrinkage parameters for ridge regression methods. [PDF]

open access: yesSci Rep
In this study, we introduce three new shrinkage parameters for ridge regression, which dynamically adjust the ridge penalty based on the properties of the data, particularly the multicollinearity structure.
Akhtar N, Alharthi MF.
europepmc   +2 more sources

On shrinkage estimators improving the positive part of James-Stein estimator

open access: yesDemonstratio Mathematica, 2021
In this work, we study the estimation of the multivariate normal mean by different classes of shrinkage estimators. The risk associated with the quadratic loss function is used to compare two estimators. We start by considering a class of estimators that
Abdenour Hamdaoui
exaly   +2 more sources

Linear Shrinkage and Shrinkage Pretest Strategies in Partially Linear Models [PDF]

open access: yesE3S Web of Conferences, 2023
In this paper, we improved the efficiency of parameter estimation in partially linear models, where subspace information is available. We proposed linear shrinkage and shrinkage pretest estimation strategies.
Phukongtong Siwaporn   +2 more
doaj   +1 more source

Shrinkage Estimators for the Intercept in Linear and Uplift Regression

open access: yesScientific Annals of Computer Science, 2023
Shrinkage estimators modify classical statistical estimators by scaling them towards zero in order to decrease their prediction error. We propose shrinkage estimators for linear regression models which explicitly take into account the presence ...
Szymon Jaroszewicz, Krzysztof Rudas
doaj   +1 more source

Data envelopment analysis with shrinkage estimators

open access: yesOR Spectrum
Abstract Shrinkage estimators reduce estimation risk in multivariate statistics such as mean and standard deviation. They have not been used before in data envelopment analysis (DEA). By considering models of investment fund returns, we show that estimation risk can cause the range of estimates of inputs and outputs in a DEA model to ...
John D Lamb, Kai-Hong Tee
exaly   +2 more sources

Shrinkage Estimation of Linear Regression Models with GARCH Errors [PDF]

open access: yesJournal of Statistical Theory and Applications (JSTA), 2016
This paper introduces shrinkage estimators for the parameter vector of a linear regression model with con- ditionally heteroscedastic errors such as the class of generalized autoregressive conditional heteroscedastic (GARCH) errors when some of the ...
S. Hossain, M. Ghahramani
doaj   +1 more source

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