#
# Epage 163
#
# Written by:
# -- 
# John L. Weatherwax                2009-04-21
# 
# email: wax@alum.mit.edu
# 
# Please send comments and especially bug reports to the
# above email address.
# 
#-----

# version$language == "R" for R version$language == NULL for SPlus

if(is.null(version$language) == FALSE){ 
  require(alr3)
}else{
  library(alr3)
}

data(water)
attach(water)

ans <- bctrans(BSAAM~APMAM+APSAB+APSLAKE+OPBPC+OPRC+OPSLAKE, data=water)
summary(ans) 

# lets get these transformed variables into a new data frame this creates logXYZ columns:
#
waterT <- powtran(ans,lambda=c(0,0,0,0,0,0),family="power")

# lets fit the linear model suggested:
#
waterT$logBSAAM <- log(waterT$BSAAM)

m0 <- lm( logBSAAM ~ logAPMAM+logAPSAB+logAPSLAKE+logOPBPC+logOPRC+logOPSLAKE, data=waterT )
summary(m0)

residual.plots( m0 )

mmps( m0 )