r - 如何在R中选择性地定位y轴上的重叠点

Question

我想知道如何让我的分类变量在图中以特定顺序出现？现在 y =YZ 处的绿点位于 (1,1) 上，但 y =YZ 处的绿点更像 (1,2.2)。我完全希望它在 (1,YZ) 上。

如何指定我的点的确切坐标？

任何帮助，将不胜感激！

 x<- c("1","1","1","1","1")

    y <- c("XY","XY","XY","YZ","YZ")

    z <- c("Treatment 1","Treatment 2","Treatment 3","Treatment 1","Treatment 2")

    data<- data.frame (x,y,z)

    ggplot(data=data,aes (x=y, y=x, color = z)) + 
    coord_flip() +
    geom_point(pch = 16, size = 3, position = position_dodge(width = 0.2)) +
    xlab("ID") +
    ylab("Time") + 
    theme(axis.text.x = element_text(angle = 90, hjust = 1, vjust=0.5))