| glasses {localdepth} | R Documentation |
The dataset gives the compositions of 73 glass specimens excavated in a series of archeological campaign in the island of Venice lagoon and nearby borders.
data(glasses)
Data frame with 73 observations on the following 14 variables.
IDCLASIO2AL2O3NA2OK2OCAOMGOFE2O3TIO2P2O5CLSO3MNOVariables SIO2 to MNO are provide composition of glass specimens on the corresponding chemical compound.
Mario Romanazzi.
M. Verita', A. Renier and S. Zecchin (2002) Chemical analyses of ancient glass findings excavated in the venetian lagoon. Journal of Cultural Heritage, 3, 261-271.
glasses <- na.omit(glasses[,-1])
n <- nrow(glasses)
p <- ncol(glasses)
col <- rep("black",n)
col[glasses[,1] == 2] <- "red"
col[glasses[,1] == 3] <- "green"
lab <- rep("M",n)
lab[glasses[,1] == 1] <- "V"
lab[glasses[,1] == 2] <- "R"
lab1 <- paste(lab,1:n,sep="")
pc <- princomp(glasses[,-1],cor=TRUE)
summary(pc)
plot(scale(pc$scores[,1]),scale(pc$scores[,2]),pch=20, xlab="PC1 (36)", ylab="PC2 (28)", main="Roman Venetian Glasses Data")
text(scale(pc$scores[,1]),scale(pc$scores[,2]), labels=lab1,cex=0.6,pos=3,col=col)
abline(h=0,v=0,lty="dashed",col="grey")
plot(scale(pc$scores[,1]),scale(pc$scores[,3]),pch=20, xlab="PC1 (36)", ylab="PC3 (11)", main="Roman Venetian Glasses Data")
text(scale(pc$scores[,1]),scale(pc$scores[,3]), labels=lab1,cex=0.6,pos=3,col=col)
abline(h=0,v=0,lty="dashed",col="grey")
plot(scale(pc$scores[,2]),scale(pc$scores[,3]),pch=20, xlab="PC2 (28)", ylab="PC3 (11)", main="Roman Venetian Glasses Data")
text(scale(pc$scores[,2]),scale(pc$scores[,3]), labels=lab1,cex=0.6,pos=3,col=col)
abline(h=0,v=0,lty="dashed",col="grey")
set.seed(1234)
err1 <- rnorm(n,0,sd(glasses[,2])/100)
err2 <- rnorm(n,0,sd(glasses[,3])/100)
err3 <- rnorm(n,0,sd(glasses[,4])/100)
err4 <- rnorm(n,0,sd(glasses[,5])/100)
err5 <- rnorm(n,0,sd(glasses[,6])/100)
err6 <- rnorm(n,0,sd(glasses[,7])/100)
err7 <- rnorm(n,0,sd(glasses[,8])/100)
err8 <- rnorm(n,0,sd(glasses[,9])/100)
err9 <- rnorm(n,0,sd(glasses[,10])/100)
err10 <- rnorm(n,0,sd(glasses[,11])/100)
err11 <- rnorm(n,0,sd(glasses[,12])/100)
err12 <- rnorm(n,0,sd(glasses[,13])/100)
glasses <- glasses[,-1] + data.frame(err1,err2,err3,err4,err5,err6,err7,err8,err9, err10,err11,err12)
tau <- quantile.localdepth(glasses, probs=c(0.1, 0.9), method='mahalanobis')
gla10 <- localdepth(glasses, tau=tau[1], method='mahalanobis')
gla90 <- localdepth(glasses, tau=tau[2], method='mahalanobis')
plot(gla10)
abline(0, 1, lty=2)
plot(gla90)
abline(0, 1, lty=2)