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Is there a way to add confidence intervals to a qqplot?

I have a dataset of gene expression values, which I've visualized using PCA:

pca1 = prcomp(data, scale. = TRUE)

I'm now looking for outliers by checking the distribution of the data against the normal distribution through:

qqnorm(pca1$x,pch = 20, col = c(rep("red", 73), rep("blue", 33)))

qqline(pca1$x)

This is my data:

data = [2.48 104 4.25 219 0.682 0.302 1.09 0.586 90.7 344 13.8 1.17 305 2.8 79.7 3.18 109 0.932 562 0.958 1.87 0.59 114 391 13.5 1.41 208 2.37 166 3.42]

I would now like to plot 95% confidence intervals to check which data points lie outside. Any tips on how to do this?

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1 回答 1

15

该库car提供了qqPlot(...)默认情况下向普通 qq-plot 添加逐点置信包络的功能：

library(car)
qqPlot(pca1$x)
于 2013-10-11T13:23:48.230 回答