Tobias,
Great, works like a charm! I'm already seeing all kinds of patterns that were invisible before. I appreciate your help.
-Erik
On 15/01/2005, at 16:30, Tobias Verbeke wrote:
On Sat, 15 Jan 2005 15:53:18 +0100 List account <[EMAIL PROTECTED]> wrote:
Thanks, Tobias for the response.
I tried the suggestion you gave, and apparently (at least according to the biplot manpage, only the first two members of the col vector are used, the first to plot the first set of values, i.e. the scores, and the second color is used for the loadings (I think I have that right). At any rate, if I add the clause 'col = c(rep("red", 100), rep("blue", 17), rep("green", 62))' I just get a bunch of red points! :(
You're right. I'm sorry I did not read ?biplot, but only checked it had
a col argument (Semel in anno licet insanire..).
Anyway, with PCA it is not a good idea to plot both variables and
cases on one single plot, because the temptation is too great to interpret
proximities between variables and cases. You'd better plot two different
graphs, one for the cases and one for the `circle of correlations'.
For plotting the cases, you could make up your own plot using something similar to this:
library(MASS) # for eqscplot F1 <- yourpca$score[,1] F2 <- yourpca$score[,2] eqscplot(F1, F2, pch = 20) text(F1, F2, labels = names(F1), col = c(rep("red", 100), rep("blue", 17), rep("green", 62)), pos = 3)
Tobias
Si vales, valeo...
-Erik
______________________________________________
[email protected] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
