将百分比标签添加到堆叠条形图

Question

I would like to add percentage labels to stacked barplot using ggplo2. Here is my code. It does not work so far.

df <- longer_data %>% 
  drop_na(response) %>%
  group_by(question) %>%
  count(response) %>%
  mutate(prop = percent(response / sum(response))) %>%
  mutate(response = factor(response, levels = 1:3, labels = c("Yes", "No", "I don't know"))) %>% 
  mutate(prop = percent(response / sum(response))) %>%
  ggplot(df, aes(x = question, fill = response)) +
  geom_bar(stat= "count", position = "fill") +
  labs(title =" Please indicate which part of the driving task shown on the interface are \n performed by the car or you, the driver of the car.", subtitle =" Speed and distance control" )+scale_fill_manual(values = c("Yes" = "Forestgreen", "No" = "Darkred", "I don't know" = "Grey")) +labs(x ="HMIs", y = "Percentage") +scale_y_continuous(labels = scales::percent) +theme(axis.text.x = element_text(angle = 360, hjust = 0)) 

Here is a snippet of my data:

structure(list(question = c("HMI1", "HMI2", "HMI3", "HMI4", "HMI5",
  "HMI6", "HMI1", "HMI2", "HMI3", "HMI4"), response = c("1", "1",
   "1", "1", "1", "1", "1", "1", "1", "3")), 
   row.names = c(NA, -10L ), class = c("tbl_df", "tbl", "data.frame"))

Answer 1

Basically you were on the right track. Easiest way is probably to aggregate your dataset before passing it to ggplot2.

1. To get the data wrangling right:

• count by question and response
• compute the prop of of each response by question

2. Plot

• map prop on y
• add percentage labels to the bars via geom_text . As we have a stacked bar chart we have to set the position for the labels also to position_stack where I used vjust =.5 to put the labels in the middle of each bar.

library(dplyr)
library(tidyr)
library(ggplot2)
library(scales)

df <- longer_data %>%
  drop_na(response) %>%
  count(question, response) %>%
  group_by(question) %>% 
  mutate(prop = n / sum(n),
         response = factor(response, levels = 1:3, labels = c("Yes", "No", "I don't know")))

ggplot(df, aes(x = question, y = prop, fill = response)) +
  geom_col() +
  geom_text(aes(label = percent(prop)), position = position_stack(vjust = .5)) +
  labs(title = " Please indicate which part of the driving task shown on the interface are\nperformed by the car or you, the driver of the car.", 
       subtitle = " Speed and distance control") +
  scale_fill_manual(values = c("Yes" = "Forestgreen", "No" = "Darkred", "I don't know" = "Grey")) +
  labs(x = "HMIs", y = "Percentage") +
  scale_y_continuous(labels = scales::percent) +
  theme(axis.text.x = element_text(angle = 360, hjust = 0))