VSS.scree: Plot the successive eigen values for a scree test
Description
Cattell's scree test is one of most simple ways of testing the number of components or factors in a correlation matrix. Here we plot the eigen values of a correlation matrix as well as the eigen values of a factor analysis.
Usage
scree(rx,factors=TRUE,pc=TRUE,main="Scree plot",hline=NULL,add=FALSE)
VSS.scree(rx, main = "scree plot")
Arguments
rx
a correlation matrix or a data matrix. If data, then correlations are found using pairwise deletions.
factors
If true, draw the scree for factors
pc
If true, draw the scree for components
hline
if null, draw a horizontal line at 1, otherwise draw it at hline (make negative to not draw it)
main
Title
add
Should multiple plots be drawn?
Details
Among the many ways to choose the optimal number of factors is the scree test. A better function to show the scree as well as compare it to randomly parallel solutions is found found in fa.parallel