如何在 geom_count ggplot 中为道具图例下方的 stat_summary 点添加第二个图例？

Question

我有一个 geom_count 图并使用 stat_summary 添加 Y 轴（重要性）的平均值作为点。我希望点的形状（在我的例子中是红色矩形）成为图例的一部分，以便很明显这些是方法。如何让手段符号显示在道具图例下方的图例中？

#example data:
df <- data.frame(x = c("A", "B", "C", "D", "E"),
                   y = c(1, 2, 3, 4, 5, 5, 4, 3, 2, 1))

#plot
ggplot(df, aes(x = x, y =  y)) +
 geom_count(aes(size= after_stat(prop), group=x)) + 
 theme_bw() +
 scale_size_area(max_size = 8) +
 stat_summary(
   geom = "point",
   fun = "mean",
   col = "black",
   size = 6,
   shape = 23,
   fill = "red",
   show.legend = F) +
 xlab("") +
 ylab("Importance") + 
 scale_y_continuous(labels=c("1" = "Not at all", "2" = "Little ", "3" = "Moderate", "4" = "Quite"  , "5" =  "Very")) +
 theme(axis.text.x = element_text(angle = 30, vjust = 1, hjust=1),
       axis.text.y = element_text(angle =30))

改为show.legend = T并不能解决问题

我已经尝试了 but could not get it to work in my graph. Using the suggestions of this previous SO question中建议的解决方案我添加了代码

  geom_point(aes(shape = "mean"), alpha = 0)+  
  guides(shape=guide_legend(title=NULL, override.aes = list(alpha = 1)))

... 这帮助我在图例中添加了一个方法点，但我无法添加正确的形状 (see this plot here)

Answer 1

使用scale_shape_manual:

df <- data.frame(x = c("A", "B", "C", "D", "E"),
                 y = c(1, 2, 3, 4, 5, 5, 4, 3, 2, 1))

# Plot
ggplot(df, aes(x = x, y =  y)) +
  geom_count(aes(size= after_stat(prop), group=x)) + 
  theme_bw() +
  scale_size_area(max_size = 8) +
  xlab("") +
  ylab("Importance") + 
  scale_y_continuous(labels=c("1" = "Not at all", "2" = "Little ", "3" = "Moderate", "4" = "Quite"  , "5" =  "Very")) +
  theme(axis.text.x = element_text(angle = 30, vjust = 1, hjust=1),
        axis.text.y = element_text(angle =30)) +

  # Stat_summary and legend
  stat_summary(fun = mean, aes(shape = "Mean"), geom = 'point', col = "black", fill = "red", size = 6) +
  scale_shape_manual(values=c("Mean" = 23))

如何在 geom_count ggplot 中为道具图例下方的 stat_summary 点添加第二个图例？

How to add a second legend for stat_summary point below prop legend in geom_count ggplot?

r

legend

ggplot2