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tellus_CoDA_script.R
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tellus_CoDA_script.R
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### -----------------------------------------------------------------------
### "Aitchison's Compositional Data Analysis 40 years On: A Reappraisal"
### This is the analysis of Tellus cation data with zeros
### Set your working directory where the data have been donwloaded
### Software note:
### package easyCODA required
library(easyCODA)
### For the FINDALR function, either make sure you have the latest version of easyCODA
### (presently version 0.35.1 on RForge)
### or if you have installed from CRAN include the function directly from GitHub as follows:
### source("https://raw.githubusercontent.com/michaelgreenacre/CODAinPractice/master/FINDALR.R")
TELLUS <- read.table("tellus.xrf.a.cation.txt", header=TRUE)
dim(TELLUS)
# [1] 6799 61
colnames(TELLUS)
# [1] "Sample" "Easting" "Northing" "Unitname" "AgeBracket" "col"
# [7] "ab" "pH" "LOI" "Si" "Al" "Fe"
# [13] "Mg" "Mn" "Ca" "Na" "K" "P"
# [19] "Ti" "S" "Ag" "As" "Ba" "Bi"
# [25] "Br" "Cd" "Ce" "Cl" "Co" "Cr"
# [31] "Cs" "Cu" "Ga" "Ge" "Hf" "I"
# [37] "In" "La" "Mo" "Nb" "Nd" "Ni"
# [43] "Pb" "Rb" "Sb" "Sc" "Se" "Sm"
# [49] "Sn" "Sr" "Ta" "Te" "Th" "Tl"
# [55] "U" "V" "W" "Y" "Yb" "Zn"
# [61] "Zr"
### Age Brackets (AB)
table(TELLUS[,7])
# CzOl CzPl Mes NeoP Pg Pl PlCr PlDv PlOr PlSi
# 154 1691 330 1013 124 170 1534 304 1311 168
AB <- as.numeric(factor(TELLUS[,7]))
table(AB)
# 1 2 3 4 5 6 7 8 9 10
# 154 1691 330 1013 124 170 1534 304 1311 168
ABnames <- unique(TELLUS[,7])
ABnames <- sort(ABnames)
### Tellus cation data, with zeros
tellus0 <- TELLUS[,10:61]
dim(tellus0)
# [1] 6799 52
### Number of zeros and percentage of total
sum(tellus0==0)
# [1] 3883
100*sum(tellus0==0)/(nrow(tellus0)*ncol(tellus0))
# [1} 1.098295
colSums(tellus0==0)
# Si Al Fe Mg Mn Ca Na K P Ti S Ag As Ba Bi Br Cd Ce
# 0 0 0 0 0 0 0 0 0 0 2535 0 1 0 480 0 0 0
# Cl Co Cr Cs Cu Ga Ge Hf I In La Mo Nb Nd Ni Pb Rb Sb
# 0 0 0 0 2 48 0 0 0 0 0 92 0 581 0 0 0 0
# Sc Se Sm Sn Sr Ta Te Th Tl U V W Y Yb Zn Zr
# 41 0 0 0 0 59 0 1 0 10 0 33 0 0 0 0
### Number of samples with some zeros
length(which(rowSums(tellus0==0)>0))
# [1] 3303
table(rowSums(tellus0==0))
# 0 1 2 3 4 5
# 3496 2851 332 113 6 1
### minimum positive values observed
tellus.min <- min(tellus0[tellus0[,1]>0,1])
for(j in 2:52) tellus.min <- c(tellus.min, min(tellus0[tellus0[,j]>0,j]))
### replace by 2/3 minimum positive value to form matrix tellus
tellus <- tellus0
for(j in 1:52) {
if(sum(tellus0[,j]==0) > 0) {
for(i in 1:nrow(tellus)) tellus[tellus0[,j]==0,j] <- tellus.min[j]*2/3
}
}
sum(tellus==0)
# [1] 0
### Data matrices are tellus: with replaced values; tellus0: with zeros
### .pro are the normalized/closed profiles
tellus.pro <- tellus/rowSums(tellus)
tellus0.pro <- tellus0/rowSums(tellus0)
### Negative correlations in the original Tellus data and closed data
tellus0.cor <- cor(tellus0)
sum(as.dist(tellus0.cor)<0)/length(as.dist(tellus0.cor))
# [1] 0.387632
tellus0.pro.cor <- cor(tellus0.pro)
sum(as.dist(tellus0.pro.cor)<0)/length(as.dist(tellus0.pro.cor))
# [1] 0.3989442
### Table of positive and negative correlations in original and closed data
table(as.dist(tellus0.cor)>0, as.dist(tellus0.pro.cor)>0)
# FALSE TRUE
# FALSE 307 207
# TRUE 222 590
### average percentages of elements
round(100*colMeans(tellus.pro),5)
# Si Al Fe Mg Mn Ca Na K P
# 66.71287 17.22345 4.76249 3.06781 0.09769 1.83961 2.36898 2.30087 0.31112
# Ti S Ag As Ba Bi Br Cd Ce
# 0.75834 0.35673 0.00003 0.00133 0.02041 0.00002 0.00855 0.00005 0.00223
# Cl Co Cr Cs Cu Ga Ge Hf I
# 0.06613 0.00209 0.02024 0.00021 0.00530 0.00142 0.00014 0.00024 0.00080
# In La Mo Nb Nd Ni Pb Rb Sb
# 0.00002 0.00118 0.00007 0.00104 0.00076 0.00640 0.00237 0.00460 0.00009
# Sc Se Sm Sn Sr Ta Te Th Tl
# 0.00216 0.00012 0.00029 0.00021 0.00758 0.00004 0.00001 0.00018 0.00003
# U V W Y Yb Zn Zr
### rare earth correlations vs. in full composition
rare <- c(29, 18, 32, 37, 39, 49, 50, 44, 46)
tellus0.rare.pro <- CLOSE(tellus0.pro[,rare])
round(cor(tellus0.rare.pro), 3)
# La Ce Nd Sc Sm Y Yb Th U
# La 1.000 0.920 0.218 -0.910 0.328 -0.344 0.292 0.625 0.412
# Ce 0.920 1.000 0.176 -0.910 0.353 -0.368 0.319 0.618 0.398
# Nd 0.218 0.176 1.000 -0.396 -0.694 0.123 -0.722 0.328 -0.249
# Sc -0.910 -0.910 -0.396 1.000 -0.224 0.069 -0.186 -0.724 -0.464
# Sm 0.328 0.353 -0.694 -0.224 1.000 -0.312 0.990 -0.032 0.603
# Y -0.344 -0.368 0.123 0.069 -0.312 1.000 -0.300 0.056 -0.028
# Yb 0.292 0.319 -0.722 -0.186 0.990 -0.300 1.000 -0.046 0.588
# Th 0.625 0.618 0.328 -0.724 -0.032 0.056 -0.046 1.000 0.311
# U 0.412 0.398 -0.249 -0.464 0.603 -0.028 0.588 0.311 1.000
round(cor(tellus0.pro[,rare]), 3)
# La Ce Nd Sc Sm Y Yb Th U
# La 1.000 0.892 0.830 -0.208 0.175 0.479 0.117 0.612 0.332
# Ce 0.892 1.000 0.741 -0.167 0.173 0.403 0.129 0.551 0.251
# Nd 0.830 0.741 1.000 0.033 -0.207 0.627 -0.263 0.546 0.233
# Sc -0.208 -0.167 0.033 1.000 -0.074 0.313 -0.044 -0.388 -0.149
# Sm 0.175 0.173 -0.207 -0.074 1.000 0.032 0.985 -0.009 0.322
# Y 0.479 0.403 0.627 0.313 0.032 1.000 0.024 0.459 0.543
# Yb 0.117 0.129 -0.263 -0.044 0.985 0.024 1.000 -0.036 0.312
# Th 0.612 0.551 0.546 -0.388 -0.009 0.459 -0.036 1.000 0.429
# U 0.332 0.251 0.233 -0.149 0.322 0.543 0.312 0.429 1.000
### should we weight the parts?
tellus.clr.unw <- CLR(tellus.pro, weight=FALSE)$LR
tellus.clr.unw.var <- apply(tellus.clr.unw, 2, var)
tellus.pro.cm <- colMeans(tellus.pro)
### ---------------------------------------------------
### Figure 4: plotting CLR variances against part means
### (pdf and dev.off functions commented out, can be used for saving PDFs)
# pdf(file="Fig_4.pdf", width=5, height=5, useDingbats=FALSE, family="ArialMT")
par(mar=c(4.2,4,1,1), font.lab=2, las=1, mfrow=c(1,1))
plot(tellus.pro.cm, tellus.clr.unw.var, log="xy", type="n",
xlab="Average compositional values (log-scale)", ylab="Variance of CLR (log-scale)")
text(tellus.pro.cm, tellus.clr.unw.var, labels=colnames(tellus), col="red", font=4, cex=0.8)
# dev.off()
### ---------------------------------------------------
### seems like unweighted OK: no tendency for rarer elements to have much higher variance
### in fact Al, the second highest component, has the lowest CLR variance
### variances and their contributions to total
TotVar <- mean(tellus.clr.unw.var)
TotVar
# [1] 0.3446613
### sort the part contributions to variance
sort(100*tellus.clr.unw.var/sum(tellus.clr.unw.var), decreasing=TRUE)
# Nd Br S Cl Mn Ni I Cr
# 10.9354250 5.5526814 5.5490654 5.3977073 5.1673774 4.2466589 3.8078010 3.4451737
# Rb Cu Co Ga Pb Sc Se Cd
# 3.4010389 2.9310840 2.8993020 2.6291876 2.1762499 2.0443790 2.0355740 2.0174516
# : : : : : : : :
# : : : : : : : : Sm Nb Ge Al
# Sm Nb Ge Al
# 0.3686688 0.3586418 0.3582653 0.1494869
### find the denominator part for an ALR transformation
(tellus.findalr <- FINDALR(tellus.pro))
# $tot.var
# [1] 0.3446107
# $procrust.cor
# [1] 0.9662964 0.9907692 0.9339259 0.9545244 0.8336251 0.8938565 0.8945049 0.9181235 0.9289943
# [10] 0.9633254 0.8580249 0.9636980 0.8731239 0.9593046 0.8155351 0.8670293 0.8849160 0.9726034
# [19] 0.8794430 0.8981615 0.8811368 0.9300113 0.8417604 0.8948470 0.9663585 0.9619381 0.8150313
# [28] 0.9465207 0.9696384 0.8760541 0.9826409 0.7984858 0.8619365 0.8771585 0.8727109 0.9585282
# [37] 0.8797559 0.9212887 0.9892701 0.9690770 0.8738061 0.8632258 0.9623934 0.9128071 0.9812157
# [46] 0.9062143 0.9344361 0.9084048 0.9631968 0.9889152 0.8965161 0.9197674
# $procrust.max
# [1] 0.9907692
# $procrust.ref
# [1] 2
# $var.log
# [1] 0.01105921 0.03038162 0.33140143 0.17374619 0.95729658 0.39101702 0.20187174 0.21395846 0.14493670
# [10] 0.13661518 1.33979835 0.18759453 0.43182290 0.07191086 0.34766988 1.34610010 0.53016945 0.08702211
# [19] 1.24307113 0.60417549 0.63413672 0.24444501 0.63733602 0.41873633 0.12317329 0.05033178 0.97267331
# [28] 0.27404725 0.09099433 0.20412732 0.05161335 1.79752728 0.87174489 0.58182783 0.46392747 0.24809741
# [37] 0.41898994 0.59088562 0.12563614 0.18092795 0.24537927 0.27541449 0.16340938 0.26874333 0.16899488
# [46] 0.30902500 0.36712962 0.35735229 0.10523465 0.12860962 0.34451145 0.17111440
# $var.min
# [1] 0.01105921
# $var.ref
# [1] 1
### (notice that Si has lowest variance of log, but Al had lowest variance of CLR
### Al has highest Procrustes correlation and the second lowest variance of log
### 5-number summary of log(Al)
quantile(log(tellus.pro[,"Al"]), c(0.025, 0.25, 0.5, 0.75, 0.975))
# 2.5% 25% 50% 75% 97.5%
# -2.179636 -1.863984 -1.758703 -1.658929 -1.480048
### -------------------------------------------------
### Figure 5: diagnosis of the reference part for ALR
### (pdf and dev.off functions commented out, can be used for saving PDFs)
# pdf(file="Fig_4.pdf", width=5, height=5, useDingbats=FALSE, family="ArialMT")
par(mar=c(4.2,4,1,1), font.lab=2, las=1, mfrow=c(1,1))
plot(tellus.findalr$var.log, tellus.findalr$procrust.cor, ylim=c(0.8,1),
xlab="Variance of log", ylab="Procrustes correlation")
points(tellus.findalr$var.log[2], tellus.findalr$procrust.cor[2], col="red", pch=21, bg="red")
points(tellus.findalr$var.log[1], tellus.findalr$procrust.cor[1], col="blue", pch=21, bg="blue")
text(tellus.findalr$var.log[2], tellus.findalr$procrust.cor[2], col="red", label="Al", pos=3, font=4)
text(tellus.findalr$var.log[1], tellus.findalr$procrust.cor[1], col="blue", label="Si", pos=3, font=4)
# dev.off()
### -------------------------------------------------
### ordering in terms of ALR variances (ALRs w.r.t. Al)
tellus.alr <- ALR(tellus.pro, denom=2, weight=FALSE)$LR
tellus.order.alr <- order(apply(tellus.alr, 2, var), decreasing=TRUE)
tellus.log <- log(tellus.pro[,c(1,3:52)])
### -------------------------------------------------------
### Figure S1: all log-transforms versus ALRs w.r.t. ref Al
### (pdf and dev.off functions commented out, can be used for saving PDFs)
# pdf(file="Fig_S1.pdf", width=6, height=11, useDingbats=FALSE, family="ArialMT")
### use a very tall vertical window to fit in the 51 plots in a 9-by-6 grid
par(mar=c(1,0.5,2,0.5), mgp=c(2,0.7,0), cex.axis=0.8, mfrow=c(9,6))
for(j in 1:51) plot(tellus.alr[,tellus.order.alr[j]], tellus.log[,tellus.order.alr[j]],
main=colnames(tellus)[-2][tellus.order.alr[j]], cex=0.4,
ylab="", xlab="", xaxt="n",yaxt="n", col="lightblue")
# dev.off()
### -------------------------------------------------------
### comparing distances between two samples using all logratios and using the ALRs
tellus.clr.unw <- CLR(tellus.pro, weight=FALSE)$LR
tellus.alr <- ALR(tellus.pro, denom=2, weight=FALSE)$LR
### using 10000 random distance pairs
foo <- matrix(0, nrow=10000, ncol=2)
k <- 1
set.seed(123)
sample1 <- sample(1:6799, 10000, replace=TRUE)
sample2 <- sample(1:6799, 10000, replace=TRUE)
for(i in 1:10000) {
if(sample1[i]==sample2[i]) next
foo[k,1] <- sqrt(sum((tellus.clr.unw[sample1[i],] - tellus.clr.unw[sample2[i],])^2)) / sqrt(52)
foo[k,2] <- sqrt(sum((tellus.alr[sample1[i],] - tellus.alr[sample2[i],])^2)) / sqrt(51)
k <- k+1
}
sum(foo[,2]<foo[,1])
# [1] 0 (all distances based on ALRs below the corresponding ones based on CLRs)
### ---------------------------------------------------------
### Figure 6: Scatterplot of distances based on CLRs and ALRs
### (pdf and dev.off functions commented out, can be used for saving PDFs)
# pdf(file="Fig_6.pdf", width=5, height=5, useDingbats=FALSE, family="ArialMT")
par(mar=c(4.2,4,1,1), font.lab=2, las=1)
plot(foo[,1], foo[,2], xlab="Distance based on ALRs w.r.t. Al", ylab="Logratio distance based on all LRs",
xlim=c(0,2), ylim=c(0,2), asp=1, col="lightblue", cex=0.5)
abline(a=0, b=1, col="red", lty=2)
# dev.off()
### ---------------------------------------------------------
### total variance in logratio analysis (the CLRs, equivalently all LRs)
tellus.lra <- LRA(tellus.pro, weight=FALSE)
sum(tellus.lra$sv^2)
# [1] 0.3446107
### total variance in PCA of ALRs (ref: Al)
tellus.pca <- PCA(tellus.alr, weight=FALSE)
### (remember that all total variances are averaged, not summed)
sum(tellus.pca$sv^2)
# [1] 0.3786807
### percentages of variance for CLRs in LRA
round(100*tellus.lra$sv^2/sum(tellus.lra$sv^2),3)
# [1] 45.188 23.813 4.934 3.131 2.555 2.088 1.847 1.790 1.352 1.148 1.105 1.057 0.950 0.841
# [15] 0.812 0.675 0.634 0.560 0.477 0.428 0.404 0.374 0.358 0.335 0.277 0.249 0.237 0.224
# [29] 0.204 0.195 0.171 0.167 0.157 0.146 0.141 0.132 0.119 0.110 0.105 0.088 0.083 0.073
# [43] 0.054 0.052 0.040 0.031 0.024 0.022 0.015 0.013 0.013
### percentages of variance for ALRs (ref: Al)
round(100*tellus.pca$sv^2/sum(tellus.pca$sv^2),3)
# [1] 44.893 22.101 7.330 2.914 2.606 2.083 1.801 1.713 1.461 1.231 1.065 1.013 0.912 0.807
# [15] 0.778 0.708 0.601 0.539 0.519 0.435 0.375 0.362 0.334 0.316 0.263 0.250 0.231 0.212
# [29] 0.207 0.189 0.170 0.159 0.154 0.146 0.135 0.129 0.118 0.110 0.102 0.091 0.082 0.070
# [43] 0.065 0.049 0.048 0.031 0.025 0.022 0.018 0.013 0.012
### WARD clustering of parts (i.e., on transposed matrix) using 10% of the cases
tellus.10 <- tellus.pro[seq(1,nrow(tellus), 10),]
dim(tellus.10)
# [1] 680 52
tellus.clus <- WARD(CLR(CLOSE(t(tellus.10)), weight=FALSE), weight=FALSE)
### -----------------------------------------------------------------------
### Figure 2: Ward clustering of parts
### (pdf and dev.off functions commented out, can be used for saving PDFs)
# pdf(file="Fig_2.pdf", width=10, height=5, useDingbats=FALSE, family="ArialMT")
par(mar=c(4.2,4,1,1), mgp=c(2,0.7,0), font.lab=2)
plot(tellus.clus, labels=colnames(tellus), xlab="Elements", ylab="Height", main="")
# dev.off()
### -----------------------------------------------------------------------
### Amalgamation clustering of parts (matrix not transposed) using 10% of the cases
### (this stepwise algorithm takes some time --- needs optimizing)
tellus.aclus <- ACLUST(tellus.10, weight=FALSE)
### Alternative vertical scale
tellus.aclus.alt <- tellus.aclus
tellus.aclus.alt$height <- 100*tellus.aclus$height/tellus.aclus$height[51]
### -----------------------------------------------------------------------
### Figure 3: Amalgamation clustering of parts
### (pdf and dev.off functions commented out, can be used for saving PDFs)
# pdf(file="Fig_3.pdf", width=10, height=5, useDingbats=FALSE, family="ArialMT")
par(mar=c(4.2,4,1,1), mgp=c(2,0.7,0), font.lab=2)
plot(tellus.aclus.alt, labels=colnames(tellus), xlab="Elements",
ylab="Percentage variance (%)", main="")
# dev.off()
### -----------------------------------------------------------------------
### LRA of tellus and row principal coordinates
### .rpc = row principal coordinates
tellus.lra <- LRA(tellus.pro, weight=FALSE)
tellus.lra.rpc <- tellus.lra$rowpcoord
### PCA of tellus ALRs w.r.t. Al and row principal coordinates
tellus.alr.al <- ALR(tellus.pro, denom=2, weight=FALSE)$LR
tellus.pca <- PCA(tellus.alr.al, weight=FALSE)
tellus.pca.rpc <- tellus.pca$rowpcoord
### Procrustes correlations between all-logratios and ALRs...
### ...in full space
protest(tellus.lra.rpc, tellus.pca.rpc, permutations=0)$t0
# [1] 0.9907692
### ... and in reduced 2-D space
protest(tellus.lra.rpc[,1:2], tellus.pca.rpc[,1:2], permutations=0)$t0
# [1] 0.9971027
### contribution coordinates (in LRA equal weights are 1/52)
tellus.lra.ccc <- tellus.lra$colcoord * sqrt(1/52)
### high contributors
tellus.lra.ctr <- (tellus.lra.ccc[,1]^2 > 1/ncol(tellus)) | (tellus.lra.ccc[,2]^2 > 1/ncol(tellus))
sum(tellus.lra.ctr)
[1] 25
### colours for Age Bracket groups
require(colorspace)
tellus.col <- rainbow_hcl(10, l=50, c=70)
### function add.alpha for colour transparency
add.alpha <- function(col, alpha=1){
if(missing(col))
stop("Please provide a vector of colours.")
apply(sapply(col, col2rgb)/255, 2,
function(x)
rgb(x[1], x[2], x[3], alpha=alpha))
}
tellus.col.alpha <- add.alpha(rainbow_hcl(10, l=50, c=70), 0.2)
col <- c("blue","red") # colours for possible use in graphics
tellus.pch <- c(5,3,1,2,4,5,3,1,2,4)
### -----------------------------------------------------------------------
### Figure 7: left and right figures of the LRA biplot, and Age Brackets
### save as png insert into PPT, and eventually save all as png
# invert 2nd axis for this figure (only do this once)
tellus.lra.rpc[,2] <- -tellus.lra.rpc[,2]
tellus.lra.ccc[,2] <- -tellus.lra.ccc[,2]
### use horizontal rectangular window
rescale <- 2 # for points
dim <- c(1,2)
perc.hor <- 45.2; perc.ver <- 23.8
par(mar=c(4.2,4,2,2.5), mgp=c(2,0.7,0), font.lab=2, cex.axis=0.8)
plot(1.05 * rbind(tellus.lra.rpc, rescale*tellus.lra.ccc), type = "n", asp = 1,
xlab = paste("LRA dimension ", dim[1], " (", round(perc.hor, 1), "%)", sep = ""),
ylab = paste("LRA dimension ", dim[2], " (", round(perc.ver, 1), "%)", sep = ""),
xaxt = "n", yaxt = "n", main = "")
abline(h = 0, v = 0, col = "gray", lty = 2)
axis(1)
axis(2)
axis(3, at = axTicks(3), labels =
round(axTicks(3)/rescale, 2), col = "black", col.ticks = col[2], col.axis = col[2])
axis(4, at = axTicks(4), labels =
round(axTicks(4)/rescale, 2), col = "black", col.ticks = col[2], col.axis = col[2])
arrows(0, 0, 0.92 * rescale * tellus.lra.ccc[tellus.lra.ctr, 1],
0.92 * rescale * tellus.lra.ccc[tellus.lra.ctr, 2], length = 0.1, angle = 10, col = "pink")
points(tellus.lra.rpc, pch = tellus.pch[AB], col = tellus.col.alpha[AB], font = 1, cex = 0.5)
text(rescale * tellus.lra.ccc[tellus.lra.ctr,], labels = colnames(tellus.pro)[tellus.lra.ctr],
col = "red", cex = 0.9, font = 4)
legend("bottomleft", legend=ABnames, pch=tellus.pch,
col=tellus.col, text.col=tellus.col, pt.cex=0.6, cex=0.8)
# dev.off()
require(ellipse)
# png(file="Fig_7_right.png",width=7,height=5.5,units="in",res=144)
rescale <- 3 # for ellipses
par(mar=c(4.2,4,2,2.5), mgp=c(2,0.7,0), font.lab=2, cex.axis=0.8)
plot(1.05 * 0.44*tellus.lra.rpc, type = "n", asp = 1,
xlab = paste("LRA dimension ", dim[1], " (", round(perc.hor, 1), "%)", sep = ""),
ylab = paste("LRA dimension ", dim[2], " (", round(perc.ver, 1), "%)", sep = ""),
main = "")
abline(h = 0, v = 0, col = "gray", lty = 2)
set.seed(123)
CIplot_biv(tellus.lra.rpc[,1], tellus.lra.rpc[,2], group=AB, groupcols=tellus.col,
add=TRUE, shade=TRUE, alpha=0.99,
shownames=FALSE)
set.seed(123)
CIplot_biv(tellus.lra.rpc[,1], tellus.lra.rpc[,2], group=AB, groupcols=tellus.col,
add=TRUE, shade=FALSE, groupnames=ABnames, alpha=0.99)
# dev.off()
### same for dimension reduction of ALRs (both axes reversed here,
### weights here = 1/51 for 51 ALRs
tellus.pca.rpc <- -tellus.pca$rowpcoord
tellus.pca.ccc <- -tellus.pca$colcoord * sqrt(1/51)
tellus.pca.ctr <- (tellus.pca.ccc[,1]^2 > 1/ncol(tellus)) | (tellus.pca.ccc[,2]^2 > 1/ncol(tellus))
sum(tellus.pca.ctr)
[1] 28
### -----------------------------------------------------------------------
### Figure 8: left and right figures of the ALR biplot, and Age Brackets
# save as png insert into PPT, and eventually save all as png
# png(file="Fig_8_left.png",width=7,height=5.5,units="in",res=144)
rescale <- 2 # for points
dim <- c(1,2)
perc.hor <- 44.9; perc.ver <- 22.1
par(mar=c(4.2,4,2,2.5), mgp=c(2,0.7,0), font.lab=2, cex.axis=0.8)
plot(1.05 * rbind(tellus.pca.rpc, rescale*tellus.pca.ccc), type = "n", asp = 1,
xlab = paste("PCA dimension ", dim[1], " (", round(perc.hor, 1), "%)", sep = ""),
ylab = paste("PCA dimension ", dim[2], " (", round(perc.ver, 1), "%)", sep = ""),
xaxt = "n", yaxt = "n", main = "")
abline(h = 0, v = 0, col = "gray", lty = 2)
axis(1)
axis(2)
axis(3, at = axTicks(3), labels = round(axTicks(3)/rescale, 2),
col = "black", col.ticks = col[2], col.axis = col[2])
axis(4, at = axTicks(4), labels = round(axTicks(4)/rescale, 2),
col = "black", col.ticks = col[2], col.axis = col[2])
arrows(0, 0, 0.92 * rescale * tellus.pca.ccc[tellus.pca.ctr, 1],
0.92 * rescale * tellus.pca.ccc[tellus.pca.ctr, 2],
length = 0.1, angle = 10, col = "pink")
points(tellus.pca.rpc, pch = tellus.pch[AB], col = tellus.col.alpha[AB], font = 1, cex = 0.5)
text(rescale * tellus.pca.ccc[tellus.pca.ctr,], labels = colnames(tellus.alr)[tellus.pca.ctr],
col = "red", cex = 0.9, font = 4)
legend("bottomleft", legend=ABnames, pch=tellus.pch,
col=tellus.col, text.col=tellus.col, pt.cex=0.6, cex=0.8)
# dev.off()
# png(file="Fig_8_right.png",width=7,height=5.5,units="in",res=144)
rescale <- 3 # for ellipses
par(mar=c(4.2,4,2,2.5), mgp=c(2,0.7,0), font.lab=2, cex.axis=0.8)
plot(1.05 * 0.44*tellus.lra.rpc, type = "n", asp = 1,
xlab = paste("PCA dimension ", dim[1], " (", round(perc.hor, 1), "%)", sep = ""),
ylab = paste("PCA dimension ", dim[2], " (", round(perc.ver, 1), "%)", sep = ""),
main = "")
abline(h = 0, v = 0, col = "gray", lty = 2)
require(ellipse)
set.seed(123)
CIplot_biv(tellus.pca.rpc[,1], tellus.pca.rpc[,2], group=AB, groupcols=tellus.col,
add=TRUE, shade=TRUE, alpha=0.99,
shownames=FALSE)
set.seed(123)
CIplot_biv(tellus.pca.rpc[,1], tellus.pca.rpc[,2], group=AB, groupcols=tellus.col,
add=TRUE, shade=FALSE, groupnames=ABnames, alpha=0.99)
# dev.off()
### study of the Box-Cox transformation in CA on the geometry of the parts
### should work with the columns: a 't' before 'tellus' indicates transposed
ttellus <- t(tellus.pro)
ttellus.pro <- CLOSE(ttellus)
# ttellus.clr <- CLR(ttellus.pro, weight=FALSE)
ttellus.lra <- LRA(ttellus.pro, weight=FALSE)
ttellus.lra.rpc <- ttellus.lra$rowpcoord
### for original CA/chi-square
ttellus.ca <- CA(ttellus.pro)
ttellus.ca.rpc <- ttellus.ca$rowpcoord
protest(ttellus.lra.rpc, ttellus.ca.rpc, permutations=0)$t0
# [1] 0.8663466
### Now CA/chi-square with power transformation on data with zeros replaced
### Sequence of powers down to the smallest 0.0001
BoxCox <- rep(0, 101)
k <- 1
for(alpha in c(seq(1,0.01,-0.01),0.0001)) {
foo <- ttellus.pro^alpha
foo.ca <- CA(foo)
foo.ca.rpc <- foo.ca$rowpcoord
BoxCox[k] <- protest(ttellus.lra.rpc, foo.ca.rpc, permutations=0)$t0
k <- k+1
}
### Repeat with original data zeros not replaced
ttellus0 <- t(tellus0)
ttellus0.pro <- CLOSE(ttellus0)
BoxCox0 <- rep(0, 101)
k <- 1
for(alpha in c(seq(1,0.01,-0.01),0.0001)) {
foo <- ttellus0.pro^alpha
foo.ca <- CA(foo)
foo.ca.rpc <- foo.ca$rowpcoord
BoxCox0[k] <- protest(ttellus.lra.rpc, foo.ca.rpc, permutations=0)$t0
k <- k+1
}
### What is maximum Procrustes correlation
max(BoxCox0)
# [1] 0.9431539
### For which power?
c(seq(1,0.01,-0.01),0.0001)[which(BoxCox0 == max(BoxCox0))]
# [1] 0.5
### -----------------------------------------------------------------------
### Figure 9: plots of Procrustes correlations for Box-Cox transformation
### CA for data with zeros replaced and data with original zeros
# pdf(file="Fig_9.pdf", width=5, height=5, useDingbats=FALSE, family="ArialMT")
par(mar=c(4.2,4,1,1), font.lab=2, las=1)
plot(c(seq(1,0.01,-0.01),0.0001), BoxCox, xlab="Power of Box-Cox transformation",
ylab="Procrustes correlation", type="l", lwd=2, col="blue", ylim=c(0.35,1),
bty="n", xaxt="n", yaxt="n")
axis(1, at=seq(0,1,0.1), labels=seq(0,1,0.1))
axis(2)
lines(c(seq(1,0.01,-0.01),0.0001), BoxCox0, lwd=2, col="red", lty=3)
segments(0.5,0,0.5,BoxCox0[51], col="pink", lwd=2, lty=2)
legend("bottomright", legend=c("zeros replaced","with zeros"),
bty="n",
col=c("blue","red"),
lwd=c(2,2), lty=c(1,3), cex=0.8)
# dev.off()
### -----------------------------------------------------------------------
### Dimension reduction with CA of square-root transformed compositions
### (doing it on columns as for Box-Cox, although makes no difference)
ttellus0.ca <- CA(CLOSE(ttellus0.pro^0.5))
ttellus0.ca$sv <- ttellus0.ca$sv/0.5
round(100*ttellus0.ca$sv^2/sum(ttellus0.ca$sv^2),3)
# [1] 43.384 22.532 5.194 4.729 3.068 2.649 2.119 1.832 1.591 1.436 1.152 1.116 0.987 0.813
# [15] 0.729
### note again: rows are columns, and columns are rows,
### and axes are reversed to agree with previous biplots
ttellus0.ca.cpc <- -ttellus0.ca$colpcoord
ttellus0.ca.rcc <- -ttellus0.ca$rowcoord * sqrt(ttellus0.ca$rowmass)
ttellus0.ca.ctr <- (ttellus0.ca.rcc[,1]^2 > 1/nrow(ttellus0)) | (ttellus0.ca.rcc[,2]^2 > 1/nrow(ttellus0))
sum(ttellus0.ca.ctr)
[1] 22
### -----------------------------------------------------------------------
### Figure 10: left and right figures of the CA biplot, and Age Brackets
# save as png insert into PPT, and eventually save all as png
# png(file="Fig_10_left.png",width=7,height=5.5,units="in",res=144)
rescale <- 1.5 # for points
dim <- c(1,2)
perc.hor <- 43.4; perc.ver <- 22.5
par(mar=c(4.2,4,2,2.5), mgp=c(2,0.7,0), font.lab=2, cex.axis=0.8)
plot(1.05 * rbind(ttellus0.ca.cpc, rescale*ttellus0.ca.rcc), type = "n", asp = 1,
xlab = paste("CA dimension ", dim[1], " (", round(perc.hor, 1), "%)", sep = ""),
ylab = paste("CA dimension ", dim[2], " (", round(perc.ver, 1), "%)", sep = ""),
xaxt = "n", yaxt = "n", main = "")
abline(h = 0, v = 0, col = "gray", lty = 2)
axis(1)
axis(2)
axis(3, at = axTicks(3), labels = round(axTicks(3)/rescale, 2),
col = "black", col.ticks = col[2], col.axis = col[2])
axis(4, at = axTicks(4), labels = round(axTicks(4)/rescale, 2),
col = "black", col.ticks = col[2], col.axis = col[2])
arrows(0, 0, 0.95 * rescale * ttellus0.ca.rcc[ttellus0.ca.ctr, 1],
0.95 * rescale * ttellus0.ca.rcc[ttellus0.ca.ctr, 2],
length = 0.1, angle = 10, col = "pink")
points(ttellus0.ca.cpc, pch = tellus.pch[AB], col = tellus.col.alpha[AB], font = 1, cex = 0.5)
text(rescale * ttellus0.ca.rcc[ttellus0.ca.ctr,], labels = rownames(ttellus0)[ttellus0.ca.ctr], col = "red",
cex = 0.9, font = 4)
legend("bottomleft", legend=ABnames,
pch=tellus.pch, col=tellus.col, text.col=tellus.col, pt.cex=0.6, cex=0.8)
# dev.off()
# png(file="Fig_10_right.png",width=7,height=5.5,units="in",res=144)
rescale <- 3 # for ellipses
par(mar=c(4.2,4,2,2.5), mgp=c(2,0.7,0), font.lab=2, cex.axis=0.8)
plot(1.05 * 0.5*ttellus0.ca.cpc, type = "n",
asp = 1, xlab = paste("CA dimension ", dim[1], " (",
round(perc.hor, 1), "%)", sep = ""), ylab = paste("CA dimension ", dim[2], " (",
round(perc.ver, 1), "%)", sep = ""), main = "")
abline(h = 0, v = 0, col = "gray", lty = 2)
require(ellipse)
set.seed(123)
CIplot_biv(ttellus0.ca.cpc[,1], ttellus0.ca.cpc[,2], group=AB, groupcols=tellus.col,
add=TRUE, shade=TRUE, alpha=0.99,
shownames=FALSE)
set.seed(123)
CIplot_biv(ttellus0.ca.cpc[,1], ttellus0.ca.cpc[,2], group=AB, groupcols=tellus.col,
add=TRUE, shade=FALSE, groupnames=ABnames, alpha=0.99)
# dev.off()
### Procrustes between case coordinates in LRA and corresponding ones in CA
protest(tellus.lra.rpc, ttellus0.ca.cpc, permutations=0)$t0
# [1] 0.9569627
### ---------------------------------------------------------------------------------------
### k-means clustering of LRA and ALR and CA coodinates and comparison (3-cluster solution)
### for LRA
set.seed(123)
lra.km3 <- kmeans(tellus.lra.rpc, centers=3, nstart=50, iter.max=200)
# cluster sizes
lra.km3$size
## [1] 798 4513 1488
### for PCA of ALRs (ref:Al)
set.seed(123)
pca.km3 <- kmeans(tellus.pca.rpc, centers=3, nstart=50, iter.max=200)
# cluster sizes
pca.km3$size
## [1] 842 4478 1479
# for CA of power transformed (square root)
set.seed(123)
ca.km3 <- kmeans(ttellus0.ca.cpc, centers=3, nstart=50, iter.max=200)
# cluster sizes
ca.km3$size
## 914 4396 1489
### tables of agreements
table(lra.km3$cluster, pca.km3$cluster)[c(2,3,1),c(2,3,1)]
# 2 3 1
# 2 4467 9 37
# 3 7 1470 11
# 1 4 0 794
(4467+1470+794) / 6799
# 0.9899985
table(lra.km3$cluster, ca.km3$cluster)[c(2,3,1),c(2,3,1)]
# 3 1 2
# 2 4369 45 99
# 3 17 1444 27
# 1 10 0 788
(4369+1444+788) / 6799
# 0.9708781
### adjusted Rand index
require(pdfCluster)
adj.rand.index(lra.km3$cluster, pca.km3$cluster)
# [1] 0.9708841
adj.rand.index(lra.km3$cluster, ca.km3$cluster)
# [1] 0.9142874
### Quasi-coherence
### Subcompositional incoherence exercise for regular CA using chi-square distance
### with and without square-root transformation
chidist <- function(mat,rowcol=1) {
# function to calculate chi-square distances between row or column
# profiles of a matrix
# e.g. chidist(N,1) calculates the chi-square distances between row profiles
# (for row profiles, chidist(N) is sufficient)
# chidist(N,2) calculates the chi-square distances between column profiles
mat <- as.matrix(mat)
if(rowcol==1) {
prof<-mat/apply(mat,1,sum)
rootaveprof<-sqrt(apply(mat,2,sum)/sum(mat))
}
if(rowcol==2) {
prof<-t(mat)/apply(mat,2,sum)
rootaveprof<-sqrt(apply(mat,1,sum)/sum(mat))
}
dist(scale(prof,center=FALSE,scale=rootaveprof))
}
procr.CA <- matrix(0, nrow=100, ncol=44)
procr.CA.05 <- matrix(0, nrow=100, ncol=44)
tellus.cm <- colMeans(tellus0.pro)
D.chi <- as.matrix(chidist(tellus0.pro, 2))
D.chi.05 <- as.matrix(chidist(tellus0.pro^0.5, 2))
set.seed(1234567)
for(j in seq(44,4,-2)) {
nparts <- j
for(i in 1:100) {
# find the subcompositional parts
jparts <- sample(1:52, nparts)
foo <- tellus0.pro[,jparts]
# remove parts all zeros
allzero <- which(colSums(foo)==0)
if(length(allzero)>0) {
jparts <- jparts[-allzero]
foo <- tellus.pro[,jparts]
}
# incoherence in CA via MDS of distances
D <- as.dist(D.chi[jparts, jparts])
D.05 <- as.dist(D.chi.05[jparts, jparts])
D.rpc <- cmdscale(D, eig=TRUE, k=length(jparts)-1)$points
D.rpc.05 <- cmdscale(D.05, eig=TRUE, k=length(jparts)-1)$points
# remove samples that may have all zeros
allzero <- which(rowSums(foo)==0)
if(length(allzero)>0) {
foo <- foo[-allzero,]
}
D2 <- chidist(foo, 2)
D2.05 <- chidist(foo^0.5, 2)
D2.rpc <- cmdscale(D2, eig=TRUE, k=length(jparts)-1)$points
D2.rpc.05 <- cmdscale(D2.05, eig=TRUE, k=length(jparts)-1)$points
procr.CA[i,j] <- protest(D2.rpc, D.rpc, permutations=0)$t0
procr.CA.05[i,j] <- protest(D2.rpc.05, D.rpc.05, permutations=0)$t0
}
}
procr.CA.quants <- apply(procr.CA, 2, quantile, c(0.025,0.975), na.rm=TRUE)
round(procr.CA.quants[,seq(4,44,2)],4)
# [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [,11] [,12] [,13]
# 2.5% 0.8466 0.775 0.8001 0.833 0.829 0.9121 0.8948 0.894 0.9392 0.9611 0.9531 0.9583 0.9755
# 97.5% 0.9999 1.000 1.0000 1.000 1.000 1.0000 1.0000 1.000 1.0000 1.0000 1.0000 1.0000 1.0000
# [,14] [,15] [,16] [,17] [,18] [,19] [,20] [,21]
# 2.5% 0.983 0.9852 0.9796 0.9907 0.9904 0.9898 0.9898 0.9914
# 97.5% 1.000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000
procr.CA.quants.05 <- apply(procr.CA.05, 2, quantile, c(0.025,0.975), na.rm=TRUE)
round(procr.CA.quants.05[,seq(4,44,2)],4)
# [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [,11] [,12] [,13]
# 2.5% 0.9908 0.9883 0.9914 0.9921 0.9916 0.9959 0.997 0.9973 0.9967 0.9984 0.9984 0.999 0.9987
# 97.5% 1.0000 1.0000 0.9999 1.0000 1.0000 1.0000 1.000 1.0000 1.0000 1.0000 1.0000 1.000 1.0000
# [,14] [,15] [,16] [,17] [,18] [,19] [,20] [,21]
# 2.5% 0.9995 0.9993 0.9995 0.9997 0.9997 0.9998 0.9997 0.9998
# 97.5% 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000
procr.CA.ones <- rep(0,44)
for(j in seq(4,44,2)) procr.CA.ones[j] <- sum(procr.CA[,j]>0.999)
procr.CA.ones[seq(4,44,2)]
# [1] 31 21 33 38 42 49 50 48 48 60 55 63 67 69 68 75 81 77 81 77 89
procr.CA.ones.05 <- rep(0,44)
for(j in seq(4,44,2)) procr.CA.ones.05[j] <- sum(procr.CA.05[,j]>0.999)
procr.CA.ones.05[seq(4,44,2)]
# [1] 64 54 64 61 70 75 77 80 84 88 93 97 96 99 99 100 100 100 100 100 100
### Figure 11: Levels of coherence for regular chi-square geometry
# pdf(file="Fig_11.pdf", width=5, height=5, useDingbats=FALSE, family="ArialMT")
par(mar=c(5,5,1,1), mgp=c(3.5,0.7,0), font.lab=2, las=1, mfrow=c(1,1))
plot(rep(seq(4,44,2), each=2), as.numeric(procr.CA.quants[,seq(4,44,2)]), xlab="Number of parts in subcomposition",
ylab="Procrustes correlation", bty="n", xaxt="n", ylim=c(0.75, 1.02), type="n", font.lab=2, xlim=c(4,45))
axis(1, at=seq(4,44,2), labels=seq(4,44,2))
for(j in seq(4,44,2)) segments(j, procr.CA.quants[1,j], j, procr.CA.quants[2,j], col="blue", lwd=2)
eps <- 0.2
for(j in seq(4,44,2)) segments(j-eps, procr.CA.quants[1,j], j+eps, procr.CA.quants[1,j], col="blue", lwd=2, lend=2)
for(j in seq(4,44,2)) segments(j-eps, procr.CA.quants[2,j], j+eps, procr.CA.quants[2,j], col="blue", lwd=2, lend=2)
points(seq(4,44,2), apply(procr.CA[,seq(4,44,2)], 2, median, na.rm=TRUE), pch=21, col="blue", bg="white", cex=0.9)
text(seq(4,44,2), rep(1.01, 21), labels=procr.CA.ones[seq(4,44,2)], font=2, cex=0.6)
# dev.off()
### Figure 12: as before for sqrt profiles (plot window narrower vertically)
# pdf(file="Tellus_coherence_CAsqrt.pdf", width=5, height=2.7, useDingbats=FALSE, family="ArialMT")
par(mar=c(5,5,1,1), mgp=c(3.5,0.7,0), font.lab=2, las=1, mfrow=c(1,1))
plot(rep(seq(4,44,2), each=2), as.numeric(procr.CA.quants.05[,seq(4,44,2)]), xlab="Number of parts in subcomposition",
ylab="Procrustes correlation", bty="n", xaxt="n", ylim=c(0.90, 1.01), type="n", font.lab=2, xlim=c(4,45), yaxt="n")
axis(1, at=seq(4,44,2), labels=seq(4,44,2))
axis(2, at=c(0.90, 0.95, 1.00), labels=c("0.90", "0.95", "1.00"))
for(j in seq(4,44,2)) segments(j, procr.CA.quants.05[1,j], j, procr.CA.quants.05[2,j], col="blue", lwd=2)
eps <- 0.2
for(j in seq(4,44,2)) segments(j-eps, procr.CA.quants.05[1,j], j+eps, procr.CA.quants.05[1,j], col="blue", lwd=2, lend=2)
for(j in seq(4,44,2)) segments(j-eps, procr.CA.quants.05[2,j], j+eps, procr.CA.quants.05[2,j], col="blue", lwd=2, lend=2)
points(seq(4,44,2), apply(procr.CA.05[,seq(4,44,2)], 2, median, na.rm=TRUE), pch=21, col="blue", bg="white", cex=0.9)
text(seq(4,44,2), rep(1.01, 21), labels=procr.CA.ones.05[seq(4,44,2)], font=2, cex=0.6)
# dev.off()
### for the subcomposition of rare earth minerals
jparts <- rare
D <- as.dist(D.chi[jparts, jparts])
D.rpc <- cmdscale(D, eig=TRUE, k=8)$points
foo <- tellus.pro[,jparts]
# remove parts all zeros
allzero <- which(colSums(foo)==0)
if(length(allzero)>0) {
jparts <- jparts[-allzero]
foo <- tellus.pro[,jparts]
}
# remove samples all zeros
allzero <- which(rowSums(foo)==0)
if(length(allzero)>0) {
foo <- foo[-allzero,]
}
D2 <- chidist(foo, 2)
D2.rpc <- cmdscale(D2, eig=TRUE, k=8)$points
protest(D2.rpc, D.rpc, permutations=0)$t0
# [1] 0.9723521
### same, but with square root transformation
jparts <- rare
D.chi.sqrt <- as.matrix(chidist(sqrt(tellus.pro), 2))
D.sqrt <- as.dist(D.chi.sqrt[jparts, jparts])
D.sqrt.rpc <- cmdscale(D.sqrt, eig=TRUE, k=8)$points
foo <- tellus.pro[,jparts]
# remove parts all zeros
allzero <- which(colSums(foo)==0)
if(length(allzero)>0) {
jparts <- jparts[-allzero]
foo <- tellus.pro[,jparts]
}
# remove samples all zeros
allzero <- which(rowSums(foo)==0)
if(length(allzero)>0) {
foo <- foo[-allzero,]
}
D2.sqrt <- chidist(sqrt(foo), 2)
D2.sqrt.rpc <- cmdscale(D2.sqrt, eig=TRUE, k=8)$points
protest(D2.sqrt.rpc, D.sqrt.rpc, permutations=0)$t0
# [1] 0.9984683