如何折叠R数据帧中的因子水平？
有时未正确记录一个因子的水平，例如，在某些地方记录男性的水平，在某些地方记录男性的水平，因此水平水平有两个水平。因此，如果不正确地记录了因子水平，则水平数会增加，我们需要解决此问题，因为使用这些因子水平的分析将是错误的。要将不正确的因子级别转换为适当的因子级别，我们可以使用列表函数来定义那些级别。
例子1
F<-c("Male","Ma","Fem","Female","M","Male","Mal","Male","Fe","Female","M","Fema","Ma","Femal","F","Fem","Male","Ma","Male","Female")
Rate<-rep(c(25,30,37,56),times=5)
df1<-data.frame(F,Rate)
df1输出结果
F Rate
1 Male 25
2 Ma 30
3 Fem 37
4 Female 56
5 M 25
6 Male 30
7 Mal 37
8 Male 56
9 Fe 25
10 Female 30
11 M 37
12 Fema 56
13 Ma 25
14 Femal 30
15 F 37
16 Fem 56
17 Male 25
18 Ma 30
19 Male 37
20 Female 56
levels(df1$F)<-list("Male"=c("Male","Ma","Mal","M"),"Female"=c("Female","Fe","Fem","Fema","Femal","F"))
df1
F Rate
1 Male 25
2 Male 30
3 Female 37
4 Female 56
5 Male 25
6 Male 30
7 Male 37
8 Male 56
9 Female 25
10 Female 30
11 Male 37
12 Female 56
13 Male 25
14 Female 30
15 Female 37
16 Female 56
17 Male 25
18 Male 30
19 Male 37
20 Female 56例子2
MotorCycleTypes<-c("Cru","Sp","Sport","Tour","Endu","Cruiser","Touri","Enduro","Spo","Cruise","Touring","To","Sp","End","Cruis","Cruiser","Sport","End","Tour","Enduro")
Frequency<-sample(1:30,20,replace=TRUE)
df2<-data.frame(MotorCycleTypes,Frequency)
df2输出结果
MotorCycleTypes Frequency
1 Cru 5
2 Sp 15
3 Sport 10
4 Tour 2
5 Endu 25
6 Cruiser 6
7 Touri 17
8 Enduro 5
9 Spo 15
10 Cruise 25
11 Touring 12
12 To 11
13 Sp 20
14 End 6
15 Cruis 1
16 Cruiser 12
17 Sport 21
18 End 5
19 Tour 23
20 Enduro 2
levels(df2$MotorCycleTypes)<-list("Cruise"=c("Cruiser","Cru","Cruis","Cruise"),"Sport"=c("Sport","Sp","Spo"),"Enduro"=c("Enduro","Endu","End"),"Touring"=c("Touring","Tour","To","Touri"))
df2
MotorCycleTypes Frequency
1 Cruise 5
2 Sport 15
3 Sport 10
4 Touring 2
5 Enduro 25
6 Cruise 6
7 Touring 17
8 Enduro 5
9 Sport 15
10 Cruise 25
11 Touring 12
12 Touring 11
13 Sport 20
14 Enduro 6
15 Cruise 1
16 Cruise 12
17 Sport 21
18 Enduro 5
19 Touring 23
20 Enduro 2热门推荐
10 儿子立冬祝福语简短独特
11 对当兵的祝福语简短
12 侄儿高考试祝福语简短
13 伴郎红包祝福语朋友简短
14 媳妇生日简短祝福语朋友
15 公司年会祝福语简短最好
16 元旦感恩祝福语简短大全
17 红包祝福语简短10字
18 周六早晨祝福语简短