graph biplot Biplots are a type of exploratory graph used in statistics, a generalization of the simple two-variable scatterplot. A biplot is constructed by using the singular value decomposition (SVD) to obtain a low-rank approximation to a transformed version of the data matrix X, whose n rows are the samples (also called the cases, or objects), and whose p columns are the variables. The biplot was introduced by K. Ruben Gabriel (1971). Gabriel, K. R. (1971). The biplot graphic display of matrices with application to principal component analysis. Biometrika, 58(3), 453–467. adapted from: https://en.wikipedia.org/wiki/Biplot Last accessed: 04/07/2018 Philippe Rocca-Serra biplot(x, y, var.axes = TRUE, col, cex = rep(par("cex"), 2), xlabs = NULL, ylabs = NULL, expand = 1, xlim = NULL, ylim = NULL, arrow.len = 0.1, main = NULL, sub = NULL, xlab = NULL, ylab = NULL, ...) from: http://stat.ethz.ch/R-manual/R-devel/library/stats/html/biplot.html last accessed: 04/07/2018 ready for release