Question

我正在尝试使用方差分析来查找以下数据集中仅“ group1”，“ group2”和“ group5”的均值之间的差异。

tab_csv <- read.csv("data.csv", sep = "\t", header = TRUE)
tab_csv

    label   number
1  group1    120
2  group1    105
3  group1    105
4  group1     84
5  group1     32
6  group2    820
7  group2    922
8  group2    823
9  group2    945
10 group2    849
11 group3    1990
12 group3    29
13 group3    40
14 group3    21
15 group3    900
16 group4    220
17 group4    70
18 group4    109
19 group4    19
20 group4    18
21 group5    55
22 group5    40
23 group5    35
24 group5    30
25 group5    20

levels(tab_csv$label)
[1] "group1" "group2" "group3" "group4" "group5"

我已经开始尝试此方法，但是我不确定...

tab_csv$number[tab_csv$label == "group1"])
tab_csv$number[tab_csv$label == "group2"])
tab_csv$number[tab_csv$label == "group5"])

有人可以帮忙吗？

Answer 1

这应该是您想要的吗？

newdf <- df %>%
     filter(label %in% c("group1","group2","group5"))

myaov <- aov(number ~ label, data = newdf)

Answer 2

您可以这样做：

groups<-c("group1","group2","group5")

new.df<-tab_csv[which(levels(tab_csv$label)%in%groups,] m1<-aov(new.df$number~new.df$label) summary(m1)

或者您可以从原始data.frame中提取并运行以下命令：

m2<-aov(tab_csv$number[which(tab_csv$label%in%groups)]~tab_csv$label[which(tab_csv$label%in%groups)]) summary(m2)

可能更漂亮的方法...

Answer 3

您还可以使用subset在数据框中选择组：

# 1st - generating your dataframe
group = c(rep("group1",5),rep("group2",5),rep("group3",5),rep("group4",5),rep("group5",5))
value = c(120,105,105,84,32,820,922,823,945,849,1990,29,40,21,900,220,70,109,19,18,55,40,35,30,20)
df = data.frame(group = group,value = value)


# performing anova
> summary(aov(value ~ group, data = subset(df, group == "group1" | group =="group2" | group == "group5")))
            Df  Sum Sq Mean Sq F value  Pr(>F)    
group        2 2189758 1094879   695.9 3.9e-13 ***
Residuals   12   18880    1573                    
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

如何使用ANOVA查找数据集中三组平均值之间的差异

3 个答案: