12.29 四象限图

dat <- data.frame(
  perc = c(54, 18, 5, 15),
  wall_policy = c("oppose", "favor", "oppose", "favor"),
  dreamer_policy = c("favor", "favor", "oppose", "oppose"),
  stringsAsFactors = FALSE
) %>%
  transform(
    xmin = ifelse(wall_policy == "oppose", -sqrt(perc), 0),
    xmax = ifelse(wall_policy == "favor", sqrt(perc), 0),
    ymin = ifelse(dreamer_policy == "oppose", -sqrt(perc), 0),
    ymax = ifelse(dreamer_policy == "favor", sqrt(perc), 0)
  )

ggplot(data = dat) +
  geom_rect(aes(
    xmin = xmin, xmax = xmax,
    ymin = ymin, ymax = ymax
  ), fill = "grey") +
  geom_text(aes(
    x = xmin + 0.5 * sqrt(perc),
    y = ymin + 0.5 * sqrt(perc),
    label = perc
  ),
  color = "white", size = 10
  ) +
  coord_equal() +
  geom_hline(yintercept = 0) +
  geom_vline(xintercept = 0) +
  theme_minimal() +
  labs(x = "", y = "", title = "")

图 12.68: 四象限图