The class CovNA
represents an estimate of the
multivariate location and scatter of a data set. The objects of class CovNA
contain the classical estimates and serve as base for deriving other
estimates, i.e. different types of robust estimates.
Objects can be created by calls of the form new("CovNA", ...)
,
but the usual way of creating CovNA
objects is a call to the function
CovNA
which serves as a constructor.
call
:Object of class "language"
cov
:covariance matrix
center
:location
n.obs
:number of observations used for the computation of the estimates
mah
:mahalanobis distances
det
:determinant
flag
:flags (FALSE if suspected an outlier)
method
:a character string describing the method used to compute the estimate: "Classic"
singularity
:a list with singularity information for the
covariance matrix (or NULL
of not singular)
X
:data
Class "Cov-class"
, directly.
signature(obj = "CovNA")
: distances
signature(obj = "CovNA")
: Flags observations as outliers if the corresponding mahalanobis distance is larger then qchisq(prob, p)
where prob
defaults to 0.975.
signature(object = "CovNA")
: calculate summary information
Valentin Todorov valentin.todorov@chello.at
Todorov V & Filzmoser P (2009), An Object Oriented Framework for Robust Multivariate Analysis. Journal of Statistical Software, 32(3), 1--47. <doi:10.18637/jss.v032.i03>.