Covariance is of universal prevalence across various disciplines
within statistics. This package aims at providing a rich collection of
geometric and statistical tools for a variety of inferences on
covariance structures as well as its inverse called
precision matrix. See the package help file by
help("package-CovTools") in R console for the list of
available functions.
Installation
You can install the released version of CovTools from CRAN with:
install.packages("CovTools")
 
or the development version from github:
## install.packages("devtools")
## library(devtools)
devtools::install_github("kisungyou/CovTools")
 
List of Available Methods
We offer various methods for covariance and symmetric
positive-definite matrices. Below is the list of functions implemented
in our package.
(0) Elementary Operations
CovDist | 
computes pairwise distance for symmetric
positive-definite matrices | 
CovMean | 
estimate mean/average covariance
matrix | 
(1) Estimation : Covariance
CovEst.adaptive | 
Cai and Liu (2011) | 
adaptive thresholding | 
CovEst.hard | 
Bickel and Levina (2008) | 
hard thresholding | 
CovEst.hardPD | 
Fan et al. (2013) | 
hard thresholding under
positive-definiteness constraint | 
CovEst.nearPD | 
Qi and Sun (2006) | 
nearest positive-definite matrix
projection | 
CovEst.soft | 
Antoniadis and Fan (2001) | 
soft thresholding | 
CovEst.2003LW | 
Ledoit and Wolf (2003) | 
linear shrinkage estimation | 
CovEst.2010OAS | 
Chen et al. (2010) | 
oracle approximation shrinkage | 
CovEst.2010RBLW | 
Chen et al. (2010) | 
Rao-Blackwell Ledoit-Wolf estimation | 
(2) Estimation : Precision
PreEst.2014An | 
An et al. (2014) | 
banded precision estimation via bandwidth
test | 
PreEst.2014Banerjee | 
Banerjee and Ghosal (2014) | 
Bayesian estimation of a banded precision
matrix | 
PreEst.2017Lee | 
Lee and Lee (2017) | 
Bayesian estimation of a banded precision
matrix | 
PreEst.glasso | 
Friedman et al. (2008) | 
graphical lasso | 
(3) Hypothesis Test : 1-sample
BCovTeset1.mxPBF | 
Lee et al. (2018) | 
Bayesian test using Maximum Pairwise Bayes
Factor | 
CovTest1.2013Cai | 
Cai and Ma (2013) | 
Test by Cai and Ma | 
CovTest1.2014Srivastava | 
Srivastava et al. (2014) | 
Test by Srivastava, Yanagihara, and
Kubokawa | 
(4) Hypothesis Test : 2-sample
CovTest2.2013Cai | 
Cai and Ma (2013) | 
Test by Cai and Ma | 
(5) Hypothesis Test :
1-sample Diagonal
BDiagTest1.mxPBF | 
Lee et al. (2018) | 
Bayesian Test using Maximum Pairwise Bayes
Factor | 
DiagTest1.2011Cai | 
Cai and Jiang (2011) | 
Test by Cai and Jiang | 
DiagTest1.2015Lan | 
Lan et al. (2015) | 
Test by Lan, Luo, Tsai, Wang, and
Yang |