如何從 p 值矩陣中獲得緊湊的字母顯示？ (How to get a compact letter display from a matrix of p-values?)

問題描述

如何從 p 值矩陣中獲得緊湊的字母顯示？ (How to get a compact letter display from a matrix of p‑values?)

考慮這個數據，我們有幾個組，每個組有 10 個觀察值，我們執行 pairwise.t.test()：

set.seed(123)
data <‑ data.frame(group = rep(letters[1:18], each = 10),
                   var = rnorm(180, mean = 2, sd = 5))
ttres <‑ pairwise.t.test(x=data$var, g=data$group, p.adjust.method = "none")#just to make sure i get some sigs for the example

您可以返回一個矩陣此測試的 p 值如下所示：

pmat <‑ as.matrix(ttres$p.value)

有了這樣的相關矩陣形狀的結果，我們如何從結果中獲得緊湊的字母顯示？我的意思是我希望以字母的形式獲得輸出，顯示哪些組不同，哪些組不同。我的意思是我希望生成 multcomp 包中的 cld 函數用於 tukeys 測試：https://www.rdocumentation。

參考解法

方法 1:

You can use the functions fullPTable() and multcompLetters(), found in the library(rcompanion) and library(multcompView).

Here is how I would solve your problem:

library(rcompanion)
library(multcompView)
set.seed(123)
data <‑ data.frame(group = rep(letters[1:18], each = 10),
                   var = rnorm(180, mean = 2, sd = 5))

PT <‑ pairwise.t.test(x=data$var, g=data$group, p.adjust.method = "none")#just to make sure i get some sigs for the example
PT = PT$p.value
PT1 = fullPTable(PT)
multcompLetters(PT1,
                compare="<",
                threshold=0.05,
                Letters=letters,
                reversed = FALSE)

(by Ryan、Andy)

參考文件

1. How to get a compact letter display from a matrix of p‑values? (CC BY‑SA 2.5/3.0/4.0)