Q-Q plot facet wrap with QQ line in R

Question

如何生成显示某些数据的 qqlines 的 qqnorm facet wrap？

This question 生成 qqplot 但没有在图上绘制真正的 qqline（只有数据的平滑 lm）。代码是从链接的问题中复制的。

library(plyr)

# create some data
set.seed(123)
df1 <- data.frame(vals = rnorm(1000, 10),
                  y = sample(LETTERS[1:3], 1000, replace = TRUE),
                  z = sample(letters[1:3], 1000, replace = TRUE))

# calculate the normal theoretical quantiles per group
df2 <- ddply(.data = df1, .variables = .(y, z), function(dat){
             q <- qqnorm(dat$vals, plot = FALSE)
             dat$xq <- q$x
             dat
}
)

# plot the sample values against the theoretical quantiles
ggplot(data = df2, aes(x = xq, y = vals)) +
  geom_point() +
  geom_smooth(method = "lm", se = FALSE) +
  xlab("Theoretical") +
  ylab("Sample") +
  facet_grid(y ~ z)

Answer 1

我认为没有必要plyr或自己打电话给qqnorm。你可以做到

ggplot(data = df1, aes(sample=vals)) +
  geom_qq() + 
  geom_qq_line(color="red") + 
  xlab("Theoretical") +
  ylab("Sample") +
  facet_grid(y ~ z)

Q-Q plot facet wrap with QQ line in R

Q-Q plot facet wrap with QQ line in R

r

ggplot2

statistics

facet