boxplot_-significance_add_star.R

library(ggpubr)

## 载入需要的程辑包：ggplot2

## Warning: 程辑包'ggplot2'是用R版本4.2.3 来建造的

# Visualize
ggboxplot(ToothGrowth, x = "dose", y = "len",
          color = "dose", palette = "jco")+
  stat_compare_means(method = "anova", label.y = 40) +      # Add global p-value
  stat_compare_means(label = "p.signif", method = "t.test",
                     ref.group = "0.5")                    # Pairwise comparison against reference

## Warning: The dot-dot notation (`..p.signif..`) was deprecated in ggplot2 3.4.0.
## i Please use `after_stat(p.signif)` instead.
## i The deprecated feature was likely used in the ggpubr package.
##   Please report the issue at <]8;;https://github.com/kassambara/ggpubr/issueshttps://github.com/kassambara/ggpubr/issues]8;;>.
## This warning is displayed once every 8 hours.
## Call `lifecycle::last_lifecycle_warnings()` to see where this warning was
## generated.

head(ToothGrowth)

##    len supp dose
## 1  4.2   VC  0.5
## 2 11.5   VC  0.5
## 3  7.3   VC  0.5
## 4  5.8   VC  0.5
## 5  6.4   VC  0.5
## 6 10.0   VC  0.5

oneway.test(len ~ dose, data = ToothGrowth, var.equal = TRUE)

## 
##  One-way analysis of means
## 
## data:  len and dose
## F = 67.416, num df = 2, denom df = 57, p-value = 9.533e-16

t.test(ToothGrowth$len[ToothGrowth$dose == 0.5], ToothGrowth$len[ToothGrowth$dose == 1])

## 
##  Welch Two Sample t-test
## 
## data:  ToothGrowth$len[ToothGrowth$dose == 0.5] and ToothGrowth$len[ToothGrowth$dose == 1]
## t = -6.4766, df = 37.986, p-value = 1.268e-07
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
##  -11.983781  -6.276219
## sample estimates:
## mean of x mean of y 
##    10.605    19.735

#http://www.sthda.com/english/articles/24-ggpubr-publication-ready-plots/76-add-p-values-and-significance-levels-to-ggplots/#compare-more-than-two-groups