geom_bar或geom_col始终从0开始，即你不能设定起始位置。相反，你可以使用geom_rect来实现你想要的结果，但是需要一些努力来计算每个酒吧的开始和结束位置：

library(ggplot2)
library(dplyr, warn = FALSE)

df <- df |>
  # Indicator for bars going down
  mutate(is_down = difference_value < 0) |>
  # Arrange dataset
  arrange(category, is_down, abs(difference_value)) |>
  # Total of bars going up
  mutate(
    total_pos = sum(difference_value[!is_down]),
    .by = category
  ) |>
  # Compute start and end of each bar
  mutate(
    ymax = cumsum(difference_value),
    ymin = lag(ymax, default = 0),
    xmin = category - .45,
    xmax = category + .45,
    .by = c(is_down, category)
  ) |>
  # Shift start and end upwards by the value of the prevoius bar
  mutate(
    across(c(ymin, ymax), ~ .x + lag(cumsum(total_pos), default = 0)),
    .by = Name
  )

ggplot(df, aes(
  fill = reorder(Name, difference_value)
)) +
  geom_rect(
    aes(xmin = xmin, xmax = xmax, ymin = ymin, ymax = ymax)
  )