Example Concentration Plot

prior_plot

library(ggplot2)
library(ggtext)
library(dplyr)

.data <- tibble(
  prior = rexp(10000, 1), 
  posterior = rlnorm(10000, 0.25, 0.2)
) |> 
  tidyr::pivot_longer(cols = everything()) |>
  mutate(name = factor(name))

subtitle <- "<span style='font-size:16pt'>
                <span style = 'color:#8F8A99;'>
                  <strong>Prior</strong>
                </span>
                & 
                <span style='color:#008080'>
                  <strong>Posterior</strong>
                </span>
              </span>"

ggplot(.data, aes(x = value, colour = name, fill = name)) +
  geom_histogram(data = subset(.data, name == 'prior'), alpha = 0.3, colour = '#8F8A99', fill = '#8F8A99', bins = 50) +
  geom_histogram(data = subset(.data, name == 'posterior'), alpha = 0.7, colour = '#008080', fill = '#008080', bins = 50) +
  labs(
    title = 'How much did the posterior update relative to the prior?',
    subtitle = subtitle,
    y = "",
    x = "σ"
  ) +
  theme(
    plot.title.position = 'plot',
    plot.caption.position = 'plot',
    text = element_text(family = 'Oxygen', size = 16),
    legend.position = 'none',
    axis.text.y = element_blank(),
    axis.ticks.y = element_blank(),
    panel.background = element_rect(fill = 'transparent'),
    plot.subtitle = element_markdown(lineheight=1.5)
  )