ggplot2 / R中条形图的偏移置信区间

Question

I'm trying to create a stripchart/dotplot with a 95% confidence interval using ggplot2 using the data posted below. I want to offset the CIs so they don't overlap the data, since it's hard to interpret them otherwise. I'm using the following code, but setting position_dodge to any number offsets the entire data set (points and CIs) rather than just the CIs. Any help would be appreciated.

dat$Index <- as.numeric(dat$Index)
dat$Group <- as.factor(dat$Group)

dodge <- position=position_dodge(2)

p <- ggplot(data=dat, aes(x=Group, y=Index, fill=Group, color=Group)) +
      geom_point(position=position_jitter(0.1), cex=3) +
      theme_classic() + expand_limits(y=c(-1.0, 1.0)) + 
      stat_summary(fun.data = mean_cl_normal, geom="errorbar", width=0, position=dodge) +
      stat_summary(fun.y = mean, fun.ymin = mean, fun.ymax=mean, geom="point", position=dodge) +  
      theme(legend.position="none") + 
      geom_abline(intercept=0, slope=0, linetype="dotted") + 
      geom_abline(intercept=1, slope=0, linetype="dotted") + 
      geom_abline(intercept=-1, slope=0, linetype="dotted")

p

Here's the dataset:

Group,Index
Ctrl,0.082
Ctrl,0.085
Ctrl,0.178
Ctrl,0.111
Ctrl,0.386
Ctrl,0.207
Hi,-0.033
Hi,0.473
Hi,0.162
Hi,-0.064
Hi,0.072
Hi,-0.027
Hi,0.166
Hi,0.007
Hi,0.048
Hi,0.091
Lo,0.145
Lo,0.104
Lo,0.128
Lo,0.032
Lo,-0.059
Lo,0.062
Lo,0.082
Lo,0.101

Answer 1

I ended up figuring out an answer, but it's not particularly elegant.

I converted the groups to numeric (1, 2, 3) and the x-axis to continuous, then defined the breaks (tick marks) as (1, 2, 3) and defined the break labels as "Ctrl, "Hi", and "Lo", thereby replacing the ticks labels with the group names.

Since the x-axis was then continuous, I could offset the data points -0.2 from the tick mark and offset the CI bar +0.2 from the tick mark, giving the separation I was looking for (see code below).

A more elegant way to do this would still be appreciated.

dat <- read.csv("ymazedi.csv", header=TRUE)dat$Index <- as.numeric(dat$Index)
dat$Group <- as.numeric(dat$Group)
breaks <- as.numeric(c(1,2,3))
labels <- c("Ctrl", "Hi", "Lo")

p <- ggplot(data=dat, aes(x=Group, y=Index, group=Code, color=Group)) +
      geom_point(aes(x=Group-0.2), position=position_jitter(.1), cex=3) +
      theme_classic() + expand_limits(y=c(-1.0, 1.0), x=c(0.5,3.5)) + 
      scale_x_continuous(breaks=breaks, labels=labels) +
      stat_summary(aes(x=Group+0.2), fun.data = mean_cl_normal, geom="pointrange", width=0) +
      theme(legend.position="none", text=element_text(size=20)) + 
      geom_abline(intercept=0, slope=0, linetype="dotted") + 
      geom_abline(intercept=1, slope=0, linetype="dotted") + 
      geom_abline(intercept=-1, slope=0, linetype="dotted")

p