I am not a great fan of pie charts since they are often used for the sake of it in circumstances where a chart is not needed at all! That said, I am willing to make an exception for “Coxcomb Plots” as pioneered by Florence Nightingale since they increase the data density on the plot and can enable comparisons across variables. Robin Lovelace has written a neat tutorial on how to create them in R, I think it’s well worth a look. He and I also recently posted this ggplot2 and spatial data tutorial, and we have more on the way!
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