如何在每个面板中添加两条回归线方程和R2值？

Question

如何在每个面板中添加两条回归线方程和R2值？

7

我希望能在每个小图中添加两条回归线方程和R2值。我使用了Jayden的函数来解决这个问题，但我发现每一个方程都相同。很可能是向函数发送了错误的数据子集。欢迎提供建议！

我的代码：

p <- ggplot(data=df,aes(x=x))+
  geom_point(aes(y = y1),size=2.0)+
  geom_smooth(aes(y = y1),method=lm,se=FALSE,size=0.5,
              fullrange = TRUE)+ # Add regression line;
  annotate("text",x = 150,y =320, label = lm_eqn(lm(y1~x,df)), # maybe wrong
           size = 2.0, parse = TRUE)+ # Add regression line equation;
  
  geom_point(aes(y = y2),size=2.0)+
  geom_smooth(aes(y = y2),method=lm,se=FALSE,size=0.5,
              fullrange = TRUE)+ # Add regression line;
  annotate("text",x = 225,y =50, label = lm_eqn(lm(y2~x,df)),
           size = 2.0, parse = TRUE)+ # Add regression line equation;
  facet_wrap(~trt)

我的数据框：

x   y1  y2  trt
22.48349    34.2    31.0    6030
93.52976    98.5    96.0    6030
163.00984   164.2   169.8   6030
205.62072   216.7   210.0   6030
265.46812   271.8   258.5   6030
23.79859    35.8    24.2    6060
99.97307    119.4   90.6    6060
189.91814   200.8   189.3   6060
268.10060   279.5   264.6   6060
325.65609   325.7   325.4   6060
357.59726   353.6   353.8   6060

我的情节：

PS. 每个面板中有两条线和你的方程式，两条线是正确的，但两个方程式是错误的。显然，右侧和左侧面板中的上/下方程式应该彼此不同。

- just_rookie

1个回答

网页内容由stack overflow 提供, 点击上面的

可以查看英文原文，
原文链接

- G. Grothendieck · Accepted Answer

1) ggplot2 尝试先将df转换为长格式（参见##行）。我们创建一个注释数据框ann，它定义了文本和在何处使用geom_text。请注意，由于图形由trt分面，因此geom_text将使用ann中每行的trt列来将该行与适当的分面相关联。

library(ggplot2)
library(reshape2)

long <- melt(df, measure.vars = 2:3) ##

trts <- unique(long$trt)
ann <- data.frame(x = c(0, 100), 
                  y = c(250, 100), 
                  label = c(lm_eqn(lm(y1 ~ x, df, subset = trt == trts[1])), 
                            lm_eqn(lm(y2 ~ x, df, subset = trt == trts[1])),
                            lm_eqn(lm(y1 ~ x, df, subset = trt == trts[2])), 
                            lm_eqn(lm(y2 ~ x, df, subset = trt == trts[2]))),
                  trt = rep(trts, each = 2),
                  variable = c("y1", "y2"))

ggplot(long, aes(x, value)) +
       geom_point() + 
       geom_smooth(aes(col = variable), method = "lm", se = FALSE,
              full_range = TRUE) + 
       geom_text(aes(x, y, label = label, col = variable), data = ann, 
             parse = TRUE, hjust = -0.1, size = 2) +
       facet_wrap(~ trt)

ann也可以这样定义：

f <- function(v) lm_eqn(lm(value ~ x, long, subset = variable==v[[1]] & trt==v[[2]]))
Grid <- expand.grid(variable = c("y1", "y2"), trt = trts)
ann <- data.frame(x = c(0, 100), y = c(250, 100), label = apply(Grid, 1, f), Grid)

继续图片后的内容：

2) lattice 在这种情况下，使用lattice可能更容易:

library(lattice)

xyplot(y1 + y2 ~ x | factor(trt), df, 
       key = simpleKey(text = c("y1", "y2"), col = c("blue", "red")),
       panel = panel.superpose, 
       panel.groups = function(x, y, group.value, ...) {
          if (group.value == "y1") {
              X <- 150; Y <- 300; col <- "blue"
          } else {
              X <- 250; Y <- 100; col <- "red"
          }
          panel.points(x, y, col = col)
          panel.abline(lm(y ~ x), col = col)
          panel.text(X, Y, parse(text = lm_eqn(lm(y ~ x))), col = col, cex = 0.7)
       }
)

（图片后续）

3）latticeExtra或者我们可以使lattice绘图更像ggplot2：

library(latticeExtra)

xyplot(y1 + y2 ~ x | factor(trt), df, par.settings = ggplot2like(),
       key = simpleKey(text = c("y1", "y2"), col = c("blue", "red")),
       panel = panel.superpose, 
       panel.groups = function(x, y, group.value, ...) {
          if (group.value == "y1") {
              X <- 150; Y <- 300; col <- "blue"
          } else {
              X <- 250; Y <- 100; col <- "red"
          }
          panel.points(x, y, col = col)
          panel.grid()
          panel.abline(lm(y ~ x), col = col)
          panel.text(X, Y, parse(text = lm_eqn(lm(y ~ x))), col = col, cex = 0.7)
       }
)

(看图后继续阅读)

注意：我们使用了此内容作为df：

df <-
structure(list(x = c(22.48349, 93.52976, 163.00984, 205.62072, 
265.46812, 23.79859, 99.97307, 189.91814, 268.1006, 325.65609, 
357.59726), y1 = c(34.2, 98.5, 164.2, 216.7, 271.8, 35.8, 119.4, 
200.8, 279.5, 325.7, 353.6), y2 = c(31, 96, 169.8, 210, 258.5, 
24.2, 90.6, 189.3, 264.6, 325.4, 353.8), trt = c(6030L, 6030L, 
6030L, 6030L, 6030L, 6060L, 6060L, 6060L, 6060L, 6060L, 6060L
)), .Names = c("x", "y1", "y2", "trt"), class = "data.frame", row.names = c(NA, 
-11L))

更新

添加了彩色文本。
添加了备用的 ann。
添加了格子解决方案。
为格子解决方案添加了 latticeExtra 变体。