title: How to plot geom_point alone plus geom_point with position_dodge
body: <p>I struggling on how I can plot my real values, present in the <code>real_values</code> vector, next to the estimates values. My problem here is that the estimates values have a range (via the <code>geom_errorbar</code>), and for the real values I would like to plot just the point, in black, on the left side of each of the 10 estimates.</p>
  <p>Here's an example of what I tried:</p>
  <pre><code>est_values = rnorm(20)
  real_values = rnorm(10)
  dat_ex =  data.frame(
            xvalues = 1:10,
            values = est_values,
            method = c(rep(&quot;A&quot;,10),rep(&quot;B&quot;,10)),
            ic_0.025 = c(est_values - rnorm(20,1,0.1)),
            ic_0.975 =  c(est_values + rnorm(20,1,0.1)))
  
  ggplot(dat_ex) +
    #geom_point(aes(x = 1:10, y= real_values), size = 2) +
    geom_point(aes(x = xvalues, y= values, group = method, colour = method),  position=position_dodge(.9), size = 3) +
    geom_errorbar(aes(x = xvalues, y= values, group = method, colour = method,ymin =  ic_0.025, ymax = ic_0.975), size = 1.3,position=position_dodge(.9), width = .2)
  </code></pre>
  <p><a href="https://i.stack.imgur.com/w1FVJ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/w1FVJ.png" alt="enter image description here" /></a></p>