Boxplot schmoxplot: How to plot means and standard errors conditioned by a factor in R?

Question

We all love robust measures like medians and interquartile ranges, but lets face it, in many fields, boxplots almost never show up in published articles, while means and sta

Answer 1

Coming a little late to the game, but this solution might be useful for future users. It uses the diamond data.frame loaded with R and takes advantage of stat_summary along with two (super short) custom functions.

require(ggplot2)

# create functions to get the lower and upper bounds of the error bars
stderr <- function(x){sqrt(var(x,na.rm=TRUE)/length(na.omit(x)))}
lowsd <- function(x){return(mean(x)-stderr(x))}
highsd <- function(x){return(mean(x)+stderr(x))}

# create a ggplot
ggplot(diamonds,aes(cut,price,fill=color))+
  # first layer is barplot with means
  stat_summary(fun.y=mean, geom="bar", position="dodge", colour='white')+
  # second layer overlays the error bars using the functions defined above
  stat_summary(fun.y=mean, fun.ymin=lowsd, fun.ymax=highsd, geom="errorbar", position="dodge",color = 'black', size=.5)