[R-lang] plotting residuals

[Kyle Gorman]

Good day list,

I have a nice instance of Zipfian (well, power law) dynamics that I've plotted (log-rank vs. log-frequency). I also fit a linear model to the data in log-space and want to show there's no interesting trend in the residuals except for at the endpoints. Simply plotting the residuals seems a bit simple, but I don't quite understand what the different measures are that are shown by calling plot() on the lm() instance. Does anyone have a particular idea about which of the four different plots is most relevant and easy to interpret/explain, or could point me to a useful resource? Also, if I end up just plotting residuals and fitting some kind of smoother to them, should I do it in the absolute space, or in something like a log and/or absolute value domain? 

Thanks,
Kyle Gorman
U of Pennsylvania