rsem.Ascov {rsem}

Sandwich-type covariance matrix

Description

Returns the sandwich type covariance matrix. This function is not intended to use seperately from the rsem.emmusig function.

Usage

rsem.Ascov(xpattern, musig, varphi=.1)

Arguments

xpattern

Missing data pattern output from rsem.pattern.

musig

Robust mean and covariance matrix from rsem.emmusig

varphi

Proportion of data to be down-weighted. Default is 0.1.

Details

Data should be a matrix. To change a data frame to a matrix, using data.matrix(x).

Value

Abeta

A matrix

Bbeta

B matrix

Gamma

Sandwich type covariance matrix

Author(s)

Ke-Hai Yuan and Zhiyong Zhang

References

Ke-Hai Yuan and Zhiyong Zhang (2011) Robust Structural Equation Modeling with Missing Data and Auxiliary Variables

See Also

rsem.emmusig

Examples

#dset<-read.table('MardiaMV25.dat.txt', na.string='-99')  
#dset<-data.matrix(dset)                                  
#n<-dim(dset)[1]
#p<-dim(dset)[2]
#miss_pattern<-rsem.pattern(n,p,dset)
#misinfo<-miss_pattern$misinfo
#V_forana<-c(1,2,4,5)
#em_results<-rsem.emmusig(dset,misinfo)
#hmu1<-em_results$mu                           
#hsigma1<-em_results$sigma
#rsem.Ascov(x, hmu1, hsigma1)