为回归线创建不同的颜色

Question

我正在创建一个散点图（大约 1,500,000 个点），并根据一个因子变量通过它运行回归（见下文“半数”）。这是图片：

如您所见，很难看到“红色”回归线。

这是数据：

  For_Cov     Per_chg      halfs
  1  0.8372001 0.002400000 upper half
  2  0.7236001 0.002800111 upper half
  3  0.6036000 0.000800000 upper half
  4  0.8540000 0.000000000 upper half
  5  0.9080001 0.003200000 upper half
  6  0.8248000 0.000000000 upper half
  7  0.1132000 0.000000000 upper half
  8  0.2044000 0.007600000 upper half
  9  0.2476001 0.085200000 upper half
  10 0.2368000 0.003600000 upper half

这是代码：

 ggplot(grid_gdp_full, aes(x = For_Cov, y = Def_Chg, group = factor(halfs))) + 
    geom_point(aes(colour = halfs), alpha = 0.1) +
    stat_smooth(method = "lm", formula = y ~ x + I(x^2), size = 4, fullrange=TRUE,     aes(group = halfs, colour = halfs), alpha = 1) +
    xlab("Initial") +
    ylab("Percent") +
    ylim(0,0.10) +
    scale_x_reverse() +
    theme_bw() +theme(
    axis.text=element_text(size=12)
    ,axis.title=element_text(size=14,face="bold")
    ,plot.background = element_blank()
    ,panel.grid.major = element_blank()
    ,panel.grid.minor = element_blank()
    ,panel.border = element_blank()
    ,panel.background = element_blank()
     ) +
     theme(axis.line = element_line(color = 'black')) 

有人如何更改代码以使回归线具有不同的颜色（回归线由 stat_smooth 创建） - 两个因子水平可能为灰色和蓝色，而不改变点的初始颜色？

这是我目前正在使用的代码，但我仍然无法获得两条不同颜色的线：

 ggplot(grid_gdp_full, aes(x = For_Cov, y = Def_Chg, fill = factor(halfs))) + 
   geom_point(aes(colour = halfs), alpha = 0.1, colour="transparent",shape=21) +
   stat_smooth(method = "lm", formula = y ~ x + I(x^2), size = 2, fullrange=TRUE, aes(group = factor(halfs)), alpha = 1) +
   xlab("Initial") +
   ylab("Percent") +
   ylim(0,0.1) +
   scale_x_reverse() +
   theme_bw() +theme(
     axis.text=element_text(size=12)
     ,axis.title=element_text(size=14,face="bold")
     ,plot.background = element_blank()
     ,panel.grid.major = element_blank()
     ,panel.grid.minor = element_blank()
     ,panel.border = element_blank()
     ,panel.background = element_blank()
   ) +
   theme(axis.line = element_line(color = 'black')) +
   scale_colour_manual(values = c("red","blue")) + 
   scale_fill_manual(values = c("grey","green"))

dev.off()

Answer 1

利用点形状 21，我们可以将 fill 用于点，colour 用于线。根据需要通过 scale_manual 设置颜色。请注意geom_point 中的colour=transparent，因此我们删除了点周围的颜色边框。

ggplot(mtcars, aes(x=cyl,y=mpg,fill=factor(gear))) +
            geom_point(aes(fill=factor(gear)),colour="transparent",shape=21) + 
            stat_smooth(aes(colour=factor(gear)),method="lm",se = FALSE) + 
            scale_colour_manual(values = c("red","blue", "green")) + 
            scale_fill_manual(values = c("orange","pink", "red"))

Answer 2

好的。我现在看到了您想要的（我认为...）：您希望线组的颜色与点组的颜色不同。本质上，您需要四种颜色：两种用于点组，两种用于线组。

这适用于您的样本，使用 For_Cov<0.5 重新编码为“更低”以拆分数据。

grid_gdp_full$halfs <- ifelse(grid_gdp_full$For_Cov<0.5,"lower half","upper half")
grid_gdp_full <- cbind(grid_gdp_full,col = 
                 ifelse(grid_gdp_full$halfs=="lower half","lm: lower","lm: upper"))

ggplot(grid_gdp_full, aes(x = For_Cov, y = Per_chg)) + 
  geom_point(aes(colour = factor(halfs)), alpha = 0.9, size=5) +
  stat_smooth(method = "lm", formula = y ~ x + I(x^2), size = 4, fullrange=TRUE,
              aes(group = col, colour = factor(col)), alpha = 1) +
  xlab("Initial") +
  ylab("Percent") +
  ylim(0,0.10) +
  scale_x_reverse() +
  theme_bw() +theme(
    axis.text=element_text(size=12)
    ,axis.title=element_text(size=14,face="bold")
    ,plot.background = element_blank()
    ,panel.grid.major = element_blank()
    ,panel.grid.minor = element_blank()
    ,panel.border = element_blank()
    ,panel.background = element_blank()
  ) +
  theme(axis.line = element_line(color = 'black')) 

产生这个：

我将点放大并设置alpha=0.9，以便您可以看到这个小样本中的点。您还颠倒了 x 轴，这使得“下”和“上”有点混乱。