compare_means() 函数

该函数主要用用法如下:

compare_means(formula, data, method = "wilcox.test", paired = FALSE,
  group.by = NULL, ref.group = NULL, ...)
  • formula:形如x~group,其中x是数值型变量,group是因子,可以是一个或者多个
  • data:数据集
  • method:比较的方法,默认为"wilcox.test", 其他可选方法为:"t.test""anova""kruskal.test"
  • paired:是否要进行paired test(TRUE or FALSE)
  • group_by: 比较时是否要进行分组
  • ref.group: 是否需要指定参考组
  • stat_compare_means()函数

    主要用法:

    stat_compare_means(mapping = NULL, comparisons = NULL hide.ns = FALSE,
                       label = NULL,  label.x = NULL, label.y = NULL,  ...)
    
  • mapping:由aes()创建的一套美学映射
  • comparisons:指定需要进行比较以及添加p-value、显著性标记的组
  • hide.ns:是否要显示显著性标记ns
  • label:显著性标记的类型,可选项为:p.signif(显著性标记)、p.format(显示p-value)
  • label.xlabel.y:显著性标签调整
  • ...:其他参数
  • 比较独立的两组

    compare_means(len~supp, data=ToothGrowth)
    aes(label=..p.format..)aes(lebel=paste0("p=",..p.format..)):只显示p-value,不显示统计检验方法
    aes(label=..p.signif..):仅显示显著性水平
    aes(label=paste0(..method..,"\n", "p=",..p.format..)):p-value与显著性水平分行显示
    

    举个栗子:

    p+stat_compare_means(aes(label=..p.signif..), label.x = 1.5, label.y = 40)
    

    利用ggpaired()进行可视化

    ggpaired(ToothGrowth, x="supp", y="len", color = "supp", line.color = "gray", 
    line.size = 0.4, palette = "jco")+ stat_compare_means(paired = TRUE)
    
    #可以指定比较哪些组
    my_comparisons <- list(c("0.5", "1"), c("1", "2"), c("0.5", "2"))
    ggboxplot(ToothGrowth, x="dose", y="len", color = "dose",palette = "jco")+
    stat_compare_means(comparisons=my_comparisons)+ # Add pairwise 
    comparisons p-value stat_compare_means(label.y = 50) # Add global p-value
    

    可以通过修改参数label.y来更改标签的位置

    ggboxplot(ToothGrowth, x="dose", y="len", color = "dose",palette = "jco")+
    stat_compare_means(comparisons=my_comparisons, label.y = c(29, 35, 40))+ # Add pairwise comparisons p-value 
    stat_compare_means(label.y = 45) # Add global p-value
    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
    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 = ".all.")#Pairwise comparison against all
    接下来利用survminer包中的数据集myeloma来讲解一下为什么有时候我们需要将ref.group设置为.all.
    
    library(survminer)#没安装的先安装再加载
    data("myeloma")
    head(myeloma)
    

    我们将根据患者的分组来绘制DEPDC1基因的表达谱,看不同组之间是否存在显著性的差异,我们可以在7组之间进行比较,但是这样的话组间比较的组合就太多了,因此我们可以将7组中每一组与全部平均值进行比较,看看DEPDC1基因在不同的组中是否过表达还是低表达。

    compare_means(DEPDC1~molecular_group, data = myeloma, ref.group = ".all.", method = "t.test")
    
    #可视化DEPDC1基因表达谱
    ggboxplot(myeloma, x="molecular_group", y="DEPDC1", 
    color = "molecular_group", add = "jitter", legend="none")+ 
    rotate_x_text(angle = 45)+ 
    geom_hline(yintercept = mean(myeloma$DEPDC1), linetype=2)+# Add horizontal line at base mean 
    stat_compare_means(method = "anova", label.y = 1600)+ # Add global annova p-value 
    stat_compare_means(label = "p.signif", method = "t.test", ref.group = ".all.")# Pairwise comparison against all
    

    从图中可以看出,DEPDC1基因在Proliferation组中显著性地过表达,而在Hyperdiploid和Low bone disease显著性地低表达

    我们也可以将非显著性标记ns去掉,只需要将参数hide.ns=TRUE

    ggboxplot(myeloma, x="molecular_group", y="DEPDC1", 
    color = "molecular_group", add = "jitter", legend="none")+
    rotate_x_text(angle = 45)+ 
    geom_hline(yintercept = mean(myeloma$DEPDC1), linetype=2)+# Add horizontal line at base mean 
    stat_compare_means(method = "anova", label.y = 1600)+ # Add global annova p-value 
    stat_compare_means(label = "p.signif", method = "t.test", ref.group = ".all.", hide.ns = TRUE)# Pairwise comparison against all
    p <- ggboxplot(ToothGrowth, x="supp", y="len", color = "supp", 
    palette = "jco", add = "jitter", facet.by = "dose", short.panel.labs = FALSE)#按dose进行分面
    #label只绘制
    p-valuep+stat_compare_means(label = "p.format")
    
    #将所有箱线图绘制在一个panel中
    p <- ggboxplot(ToothGrowth, x="dose", y="len", color = "supp", 
    palette = "jco", add = "jitter")
    p+stat_compare_means(aes(group=supp))
    p <- ggpaired(ToothGrowth, x="supp", y="len", color = "supp", 
    palette = "jco", line.color="gray", line.size=0.4, facet.by = "dose", 
    short.panel.labs = FALSE)#按dose分面
    #只显示p-value
    p+stat_compare_means(label = "p.format", paired = TRUE)
    

    条形图与线图(一个分组变量)

    #有误差棒的条形图,实际上我以前的文章里有纯粹用ggplot2实现
    ggbarplot(ToothGrowth, x="dose", y="len", add = "mean_se")+ 
    stat_compare_means()+ 
    stat_compare_means(ref.group = "0.5", label = "p.signif", label.y = c(22, 29))
    

    条形图与线图(两个分组变量)

    ggbarplot(ToothGrowth, x="dose", y="len", add = "mean_se", color = "supp", 
    palette = "jco", position = position_dodge(0.8))+ 
    stat_compare_means(aes(group=supp), label = "p.signif", label.y = 29)
    
    ggline(ToothGrowth, x="dose", y="len", add = "mean_se", color = "supp", 
    palette = "jco")+ 
    stat_compare_means(aes(group=supp), label = "p.signif", label.y = c(16, 25, 29))
    ## R version 3.4.0 (2017-04-21)
    ## Platform: x86_64-w64-mingw32/x64 (64-bit)
    ## Running under: Windows 8.1 x64 (build 9600)
    ## Matrix products: default
    ## locale:
    ## [1] LC_COLLATE=Chinese (Simplified)_China.936 
    ## [2] LC_CTYPE=Chinese (Simplified)_China.936 
    ## [3] LC_MONETARY=Chinese (Simplified)_China.936
    ## [4] LC_NUMERIC=C 
    ## [5] LC_TIME=Chinese (Simplified)_China.936 
    ## attached base packages:
    ## [1] stats graphics grDevices utils datasets methods base 
    ## other attached packages:
    ## [1] survminer_0.4.0 ggpubr_0.1.3 magrittr_1.5 ggplot2_2.2.1 
    ## loaded via a namespace (and not attached):
    ## [1] Rcpp_0.12.11 compiler_3.4.0 plyr_1.8.4
    ## [4] tools_3.4.0 digest_0.6.12 evaluate_0.10 
    ## [7] tibble_1.3.3 gtable_0.2.0 nlme_3.1-131 
    ## [10] lattice_0.20-35 rlang_0.1.1 Matrix_1.2-10 
    ## [13] psych_1.7.5 ggsci_2.4 DBI_0.6-1 
    ## [16] cmprsk_2.2-7 yaml_2.1.14 parallel_3.4.0 
    ## [19] gridExtra_2.2.1 dplyr_0.5.0 stringr_1.2.0 
    ## [22] knitr_1.16 survMisc_0.5.4 rprojroot_1.2 
    ## [25] grid_3.4.0 data.table_1.10.4 KMsurv_0.1-5 
    ## [28] R6_2.2.1 km.ci_0.5-2 survival_2.41-3 
    ## [31] foreign_0.8-68 rmarkdown_1.5 reshape2_1.4.2 
    ## [34] tidyr_0.6.3 purrr_0.2.2.2 splines_3.4.0 
    ## [37] backports_1.1.0 scales_0.4.1 htmltools_0.3.6 
    ## [40] assertthat_0.2.0 mnormt_1.5-5 xtable_1.8-2 
    ## [43] colorspace_1.3-2 ggsignif_0.2.0 labeling_0.3 
    ## [46] stringi_1.1.5 lazyeval_0.2.0 munsell_0.4.3 
    ## [49] broom_0.4.2 zoo_1.8-0


    作者:taoyan
    链接:https://www.jianshu.com/p/b7274afff14f
    來源:简书
    简书著作权归作者所有,任何形式的转载都请联系作者获得授权并注明出处。