ACSWR: cork – R documentation

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cork

The Cork Dataset

Description

Thickness of cork borings in four directions of North, South, East, and West are measured for 28 trees. The problem here is to examine if the bark deposit is same in all the directions.

Usage

data(cork)

Format

A data frame with 28 observations on the following 4 variables.

North: thickness of cork boring in the North direction
East: thickness of cork boring in the East direction
South: thickness of cork boring in the South direction
West: thickness of cork boring in the West direction

References

Rao, C. R. (1973). Linear Statistical Inference and Its Applications, 2e. J. Wiley.

Examples

data(cork)
corkcent <- cork*0
corkcent[,1] <- cork[,1]-mean(cork[,1])
corkcent[,2] <- cork[,2]-mean(cork[,2])
corkcent[,3] <- cork[,3]-mean(cork[,3])
corkcent[,4] <- cork[,4]-mean(cork[,4])
corkcentsvd <- svd(corkcent)
t(corkcentsvd$u)%*%corkcentsvd$u
t(corkcentsvd$v)%*%corkcentsvd$v
round(corkcentsvd$u %*% diag(corkcentsvd$d) %*% t(corkcentsvd$v),2)
round(corkcent,2)
corkcentsvd$d

ACSWR

A Companion Package for the Book "A Course in Statistics with R"

v1.0

GPL-2

Authors

Prabhanjan Tattar

Initial release

2015-09-05