Equality of medians with violin plot

Here’s an example code in R that performs a statistical test for equality of two group medians and plots a violin plot using the ggstatsplot library with jittered data points:

# load ggstatsplot library
library(ggstatsplot)

# generate example data
set.seed(123)
group1 <- rnorm(50, mean = 10, sd = 2)
group2 <- rnorm(50, mean = 12, sd = 2)

# perform a Wilcoxon rank sum test for medians
wilcox.test(group1, group2)

# plot a violin plot with jittered data points
ggstatsplot::ggsviolin(
  data = data.frame(
    value = c(group1, group2),
    group = c(rep("Group 1", length(group1)), rep("Group 2", length(group2)))
  ),
  x = "group",
  y = "value",
  add = "jitter",
  draw_quantiles = c(0.25, 0.5, 0.75),
  ggtheme = ggplot2::theme_bw()
)

In this example, we first generate example data for two groups (group1 and group2) using the rnorm() function. We then perform a Wilcoxon rank sum test for the medians of the two groups using the wilcox.test() function.

Finally, we use the ggsviolin() function from the ggstatsplot library to create a violin plot with jittered data points (add = "jitter") using the example data. The x and y arguments specify the variables to be plotted, and draw_quantiles specifies the quantiles to be drawn on the violin plot. The ggtheme argument specifies the theme to be used for the plot (in this case, theme_bw() from the ggplot2 library).