r - 使用 ggplot 标记异常值

Question

我正在尝试用 ggplot 标记异常值。关于我的代码，我有两个问题:

为什么它不标记低于 1.5*IQR 的异常值？

为什么它不根据异常值所在的组来标记异常值，而是显然是指数据的整体平均值？我想单独标记每个箱线图的异常值。 IE。第 1 波(调查的)中 A 国的异常值等。

我的代码示例:

PERCENT <- rnorm(50, sd = 3)
WAVE <- sample(6, 50, replace = TRUE)
AGE_GROUP <- rep(c("21-30", "31-40", "41-50", "51-60", "61-70"), 10)
COUNTRY <- rep(c("Country A", "Country B"), 25)
N <- rnorm(50, mean = 200, sd = 2)

df <- data.frame(PERCENT, WAVE, AGE_GROUP, COUNTRY, N)

ggplot(df, aes(x = factor(WAVE), y = PERCENT, fill = factor(COUNTRY))) +
  geom_boxplot(alpha = 0.3) +
  geom_point(aes(color = AGE_GROUP, group = factor(COUNTRY)), position = position_dodge(width=0.75)) +
  geom_text(aes(label = ifelse(PERCENT > 1.5*IQR(PERCENT)|PERCENT < -1.5*IQR(PERCENT), paste(AGE_GROUP, ",", round(PERCENT, 1), "%, n =", round(N, 0)),'')), hjust = -.3, size = 3)

到目前为止我所拥有的图片:




我感谢您的帮助!

Answer 1

如果你想要 IQR要按国家/地区计算，您需要对数据进行分组。您可能可以在全局范围内(即在将数据发送到 ggplot 之前)或在图层本地进行。

library(dplyr)
library(ggplot2)

ggplot(df, aes(x = as.factor(WAVE), y = PERCENT, fill = COUNTRY)) +
  geom_boxplot(alpha = 0.3) +
  geom_point(aes(color = AGE_GROUP, group = COUNTRY), position = position_dodge(width=0.75)) +
  geom_text(aes(group = COUNTRY, label = ifelse(!between(PERCENT,-1.3*IQR(PERCENT), 1.3*IQR(PERCENT)), 
                                                paste(" ",COUNTRY, ",", AGE_GROUP, ",", round(PERCENT, 1), "%, n =", round(N, 0)),'')), 
            position = position_dodge(width=0.75),
            hjust = "left", size = 3)