Usage
ggbiplot(pcobj, choices = 1:2, scale = 1, pc.biplot = TRUE, obs.scale = 1 - scale, var.scale = scale, groups = NULL, ellipse = FALSE, ellipse.prob = 0.68, labels = NULL, labels.size = 3, alpha = 1, var.axes = TRUE, circle = FALSE, circle.prob = 0.69, varname.size = 3, varname.adjust = 1.5, varname.abbrev = FALSE)
Arguments
pcobj
an object returned by prcomp() or princomp()
scale
covariance biplot (scale = 1), form biplot (scale = 0).
When scale = 1, the inner product between the variables
approximates the covariance and the distance between
the points approximates the Mahalanobis distance.
pc.biplot
for compatibility with biplot.princomp()
obs.scale
scale factor to apply to observations
var.scale
scale factor to apply to variables
groups
optional factor variable indicating the groups that
the observations belong to. If provided the points
will be colored according to groups
ellipse
draw a normal data ellipse for each group?
ellipse.prob
size of the ellipse in Normal probability
labels
optional vector of labels for the observations
labels.size
size of the text used for the labels
alpha
alpha transparency value for the points
(0 = transparent, 1 = opaque)
var.axes
draw arrows for the variables?
circle
draw a correlation circle?
(only applies when prcomp was called with scale = TRUE
and when var.scale = 1)
circle.prob
definition of circle.prob
varname.size
size of the text for variable names
varname.adjust
adjustment factor the placement of the variable names,
>= 1 means farther from the arrow
varname.abbrev
whether or not to abbreviate the variable names