使用 ggplot 绘制分类变量的比率答案

【问题标题】：Plotting ratios for categorical variables with ggplot使用 ggplot 绘制分类变量的比率
【发布时间】：2021-05-06 08:34:55
【问题描述】：

我的数据如下：

dat <- structure(list(Obstacle = structure(c(4L, 2L, 3L, 1L), .Label = c("Major Obstacle", 
"Minor Obstacle", "Moderate Obstacle", "No Obstacle", "Total"
), class = "factor"), `Crime = 1` = c(0.842430787355193, 0.724891824185835, 
0.692470837751856, 0.673805601317957), `Crime = 2` = c(0.157569212644807, 
0.275108175814165, 0.307529162248144, 0.326194398682043)), row.names = c(NA, 
4L), class = "data.frame")

            Obstacle Crime = 1 Crime = 2
1       No Obstacle 0.8424308 0.1575692
2    Minor Obstacle 0.7248918 0.2751082
3 Moderate Obstacle 0.6924708 0.3075292
4    Major Obstacle 0.6738056 0.3261944

我想将 y 轴设为比率，x 轴有序数障碍值的值，其中Crime = 1 是一条线，Crime = 2 是一条线。

我尝试过：

graph <- melt(graph, id="Obstacle")
library(ggplot2)
ggplot(data=graph,
       aes(x=Obstacle, y=value, colour=variable)) +
       geom_line()

但这会导致一个空的情节，以及 ggplot 问题：

geom_path: Each group consists of only one observation. Do you need to adjust the group aesthetic?

【问题讨论】：

标签： r ggplot2

【解决方案1】：

ggplot 信息明确，添加 group 到 aes：

graph <- reshape2::melt(dat, id = "Obstacle")

ggplot(data = graph,
       aes(x = Obstacle, y = value, colour = variable, group = variable)) +
  geom_line()

【讨论】：