R语言ggplot分组条形图geom_text标签错位问题求助

你遇到的问题是右侧蓝色条形的n标签未随条形偏移，出现错位，即便使用了position_dodge(0.9)和group参数也未解决。

问题原因 #

geom_text未正确识别分组信息，导致position_dodge偏移规则未生效。尽管全局aes设置了group=affected，但geom_text的aes中未明确关联分组映射，ggplot无法为标签应用正确的偏移逻辑。

修正后的代码 #

factor <- c("Included", "Included", "Excluded", "Excluded")
affected <- c("Affected", "Not Affected", "Affected", "Not Affected")
mean_rating <- c(76.00000, 39.55556, 49.00000, 41.62069)
n <- c(23, 2, 17, 19)

df1 <- data.frame(factor, affected, mean_rating, n)

ggplot(df1, aes(x = factor, y = mean_rating)) + 
  geom_bar(aes(fill = affected, group = affected), stat = "identity", position = position_dodge(0.9)) +
  # 在geom_text的aes中明确指定group，确保偏移生效
  geom_text(aes(label = paste("n =", n), group = affected), 
            hjust = 1, vjust = -0.35, position = position_dodge(0.9)) +
  guides(fill = FALSE, color = FALSE)

调整标签对齐方式（左侧对齐） #

如果需要让标签和条形左侧对齐，只需将hjust设置为0（原代码hjust=1是右对齐）：

ggplot(df1, aes(x = factor, y = mean_rating)) + 
  geom_bar(aes(fill = affected, group = affected), stat = "identity", position = position_dodge(0.9)) +
  geom_text(aes(label = paste("n =", n), group = affected), 
            hjust = 0, vjust = -0.35, position = position_dodge(0.9)) +
  guides(fill = FALSE, color = FALSE)

内容的提问来源于stack exchange，提问作者Noa Perlmutter