How to position labels correctly in a grouped beeswarm plot

Question

Here is a reproducible example:

library(ggplot2)
library(ggbeeswarm)

ggplot(mtcars, aes(x = factor(am), y = mpg, color = factor(am))) +
  geom_quasirandom(pch = 15, size= 6, alpha=0.7) +
  geom_text(aes(label = gear), 
            position = position_jitter(width = 0.1, height = 0), 
            vjust = -0.5, 
            size = 3) 

This code generates the following plot:

My question is: How can I accurately position the numbers within the squares on this plot?

Answer 1

You can also do this is vanilla ggplot by setting a seed in position_jitter

library(ggplot2)

ggplot(mtcars, aes(x = factor(am), y = mpg, color = factor(am))) +
  geom_point(shape = 15, size = 6, alpha = 0.7,
             position = position_jitter(width = 0.25, height = 0, seed = 31)) +
  geom_text(aes(label = gear), 
            position = position_jitter(width = 0.25, height = 0, seed = 31), 
            size = 3, color = "black") 

Answer 2

Here I found the answer How do you label a beeswarm plot in ggplot2?. There is a position_quasirandom() function in ggbeeswarm package:

library(ggplot2)
library(ggbeeswarm)

ggplot(mtcars, aes(x = factor(am), y = mpg, color = factor(am))) +
  geom_quasirandom(pch = 15, size= 6, alpha=0.7) +
  geom_text(aes(label = gear), 
            position = position_quasirandom(), 
            vjust = 0.5, 
            size = 3,
            color = "black")