Just my view on the lines/interpolate/don't interpolate controversy here:
I was taught once upon a time to plot actual data as points (with or without error bars), and plot fitted curves as lines. Only when the density of data points is so high as to make a 'mess' of the chart is it ok to plot a line representing the actual data.
YMMV Carl ______________________________________________ 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.