| CorGroups {StatDA} | R Documentation |
Correlation Matrix for Sub-groups
Description
The correlation matrix for sub-groups of data is computed and displayed in a graphic.
Usage
CorGroups(dat, grouping, labels1, labels2, legend, ndigits = 4,
method = "pearson", ...)
Arguments
dat |
data values (probably log10-transformed) |
grouping |
factor with levels for different groups |
labels1, labels2 |
labels for groups |
legend |
plotting legend |
ndigits |
number of digits to be used for plotting the numbers |
method |
correlation method: "pearson", "spearman" or "kendall" |
... |
will not be used in the function |
Details
The corralation is estimated with a non robust method but it is possible to select between the method of Pearson, Spearman and Kendall. The groups must be provided by the user.
Value
Graphic with the different sub-groups.
Author(s)
Peter Filzmoser <P.Filzmoser@tuwien.ac.at> http://cstat.tuwien.ac.at/filz/
References
C. Reimann, P. Filzmoser, R.G. Garrett, and R. Dutter: Statistical Data Analysis Explained. Applied Environmental Statistics with R. John Wiley and Sons, Chichester, 2008.
Examples
data(chorizon)
x=chorizon[,c("Ca","Cu","Mg","Na","P","Sr","Zn")]
#definition of the groups
lit=chorizon[,"LITO"]
litolog=rep(NA, length(lit))
litolog[lit==10] <- 1
litolog[lit==52] <- 2
litolog[lit==81 | lit==82 | lit==83] <- 3
litolog[lit==7] <- 4
litolog <- litolog[!is.na(litolog)]
litolog <- factor(litolog, labels=c("AB","PG","AR","LPS"))
op <- par(mfrow=c(1,1),mar=c(0.1,0.1,0.1,0.1))
CorGroups(log10(x), grouping=litolog, labels1=dimnames(x)[[2]],labels2=dimnames(x)[[2]],
legend=c("Caledonian Sediments","Basalts","Alkaline Rocks","Granites"),ndigits=2)
par(op)