>> Antony Unwin <[EMAIL PROTECTED]> >> >I must admit to being very surprised that jittering and sunflower >plots have been suggested for a dataset of 5000 points. Do those who
>mentioned these methods have examples on that scale where they are >effective?) You have a point. haha. But check the microarray literature; scatterplots have been used - often - to display microarray data with 10000 observations at a time. And in their defence, even on screen, a 600x600 pixel plot window holds 360000 pixels - 5000 is not a large fraction of that. Jittering has visible effects on data at that resolution. Compare the two plots in library(MASS) Sigma <- matrix(c(10,4,4,2),2,2) xy<- round(mvrnorm(n=5000, rep(0, 2), Sigma), 1) plot(xy,pch=".") plot(jitter(xy, factor=2),pch=".") But you're of course right to question how sensible this is. The best you can get is a visual impression of the 'shape' of the data with a greater perceived density at multiple observations which otherwise overlapped. S. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
