如何为条形图添加置信区间？

Question

我正在尝试在条形图上编写的某些代码中添加置信区间。代码如下：

Vis_Graph <- ggplot(avgtable, aes(x = reorder(Type.of.Participation, GraduatedEver), GraduatedEver, 
fill = Type.of.Participation)) +
  geom_col() +
  ggtitle("Chance of Student Graduation Rates by HIP") +
  labs(x = "Type of High Impact Practice", y = "Average Chance of Graduating (percentage)") +
  labs(colour = "Type of Participation") +
  theme(legend.position="none") +
  (MyGraphTheme)
#Print the Graph
print(Vis_Graph + MyGraphTheme)
#Reorder the graph to a horizontal layout
Vis_Graph + coord_flip()

请记住，我是一名预科大学生，参加编码班的目的是为了娱乐，所以我确定自己所学的并不是很好，但是教授向我提出挑战，要求我增加娱乐时间的置信区间，所以我给去吧。