| CA {easyCODA} | R Documentation |
Correspondence analysis
Description
Computation of correspondence analysis on a table of nonnegative data.
Usage
CA(data, nd = 2, suprow = NA, supcol = NA)
Arguments
data |
A data frame or matrix of nonnegative data (no negative values) |
nd |
Number of dimensions for summary solution if not 2 (default) |
suprow |
Indices of rows that are supplementary points |
supcol |
Indices of columns that are supplementary points |
Details
The function CA is a simple wrapper for the ca function in the ca package (Nenadic and Greenacre, 2007), for compatibility within the easyCODA package.
Supplementary rows and columns can be declared (also known as passive points) – these do not contribute to the solution but are positioned on the solution axes.
The function borrows the structure and functions of the ca package, which is required, and produces a ca object, and the same print, summary and plot methods can be used, as for a ca object.
It additionally exports the principal coordinates of both the rows and columns, not presently found in the ca package.
Value
sv |
Singular values |
nd |
Number of dimensions in solution results |
rownames |
Row names |
rowmass |
Row weights |
rowdist |
Row logratio distances to centroid |
rowinertia |
Row inertias |
rowcoord |
Row standard coordinates |
rowpcoord |
Row principal coordinates |
rowsup |
Indices of row supplementary points |
colnames |
Column names |
colmass |
Column weights |
coldist |
Column logratio distances to centroid |
colinertia |
Column inertias |
colcoord |
Column standard coordinates |
colpcoord |
Column principal coordinates |
N |
The compositional data table |
Author(s)
Michael Greenacre
References
Nenadic, O. and Greenacre, M. (2007). Correspondence analysis in R, with two- and three-dimensional graphics: The ca package. Journal of Statistical Software, 20 (3), https://www.jstatsoft.org/v20/i03/
See Also
PLOT.CA, plot.ca, summary.ca, print.ca
Examples
# (weighted) LRA of the RomanCups data set, showing default symmetric map
data(cups)
PLOT.CA(CA(cups))
data(author)
ca(author)
plot(CA(author)) # ca plot function
PLOT.CA(CA(author)) # easyCODA plot function