Hi there, I've been battling with an extension of this in my own data: getting appropriate error bars once data is stacked in a bar graph. (original question: http://r.789695.n4.nabble.com/ggplot2-se-variable-in-geom-errorbar-s-limits- td3311176.html). It wouldn't let me reply to that thread.
A modification of the earlier answer: data(diamonds) diamonds_df <- ddply(diamonds, .(cut, color), summarise, mean_price = mean(price), se_price = sd(price)/sqrt(length(price)) ) limits <- aes(ymax = mean_price + se_price, ymin = mean_price - se_price) a<-ggplot(diamonds_df, aes(x = cut, y = mean_price, fill=color)) + geom_bar(position=position_stack(width=0.9)) a Then attempting to add error bars: a+ geom_errorbar(limits, position=position_stack(width=0.9), width=0.9) I have tried: r + stat_sum_df("mean_cl_normal", geom = "errorbar"), using the aggregation function in http://www.stanford.edu/~paunesku/, using ddplyr but haven't managed to work out a way of specifying the error bars to R. In my case I would like to use an error bar analogous to each value of "cut" in the data example. When I calculate the SEs appropriately ggplot2 won't stack. This is first time posting and I've scoured the various forums and websites for a worked example. In case it is relevant, my response variable is fitted germination of an lmer model ("germination"), x is a categorical variable (treatment, with 3 levels), and I am using a categorical variable ("species") to stack. Kind regards, Olivia MSc student ______________________________________________ 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.