Question

我想通过r中的一个热编码将因子变量表示为0和1值作为data.frame。

在因子变量中，我想仅对具有三个或更多级别的变量执行一个热编码。

这是我的R代码。

german<-read.csv("http://freakonometrics.free.fr/german_credit.csv", header=TRUE)
F=c(1,2,4,5,7,8,9,10,11,12,13,15,16,17,18,19,20,21)
for(i in F) german[,i]=as.factor(german[,i])
str(german)
'data.frame':   1000 obs. of  21 variables:
 $ Creditability                    : Factor w/ 2 levels "0","1": 2 2 2 2 2 2 2 2 2 2 ...
 $ Account.Balance                  : Factor w/ 4 levels "1","2","3","4": 1 1 2 1 1 1 1 1 4 2 ...
 $ Duration.of.Credit..month.       : int  18 9 12 12 12 10 8 6 18 24 ...
 $ Payment.Status.of.Previous.Credit: Factor w/ 5 levels "0","1","2","3",..: 5 5 3 5 5 5 5 5 5 3 ...
 $ Purpose                          : Factor w/ 10 levels "0","1","2","3",..: 3 1 9 1 1 1 1 1 4 4 ...
 $ Credit.Amount                    : int  1049 2799 841 2122 2171 2241 3398 1361 1098 3758 ...
 $ Value.Savings.Stocks             : Factor w/ 5 levels "1","2","3","4",..: 1 1 2 1 1 1 1 1 1 3 ...
 $ Length.of.current.employment     : Factor w/ 5 levels "1","2","3","4",..: 2 3 4 3 3 2 4 2 1 1 ...
 $ Instalment.per.cent              : Factor w/ 4 levels "1","2","3","4": 4 2 2 3 4 1 1 2 4 1 ...
 $ Sex...Marital.Status             : Factor w/ 4 levels "1","2","3","4": 2 3 2 3 3 3 3 3 2 2 ...
 $ Guarantors                       : Factor w/ 3 levels "1","2","3": 1 1 1 1 1 1 1 1 1 1 ...
 $ Duration.in.Current.address      : Factor w/ 4 levels "1","2","3","4": 4 2 4 2 4 3 4 4 4 4 ...
 $ Most.valuable.available.asset    : Factor w/ 4 levels "1","2","3","4": 2 1 1 1 2 1 1 1 3 4 ...
 $ Age..years.                      : int  21 36 23 39 38 48 39 40 65 23 ...
 $ Concurrent.Credits               : Factor w/ 3 levels "1","2","3": 3 3 3 3 1 3 3 3 3 3 ...
 $ Type.of.apartment                : Factor w/ 3 levels "1","2","3": 1 1 1 1 2 1 2 2 2 1 ...
 $ No.of.Credits.at.this.Bank       : Factor w/ 4 levels "1","2","3","4": 1 2 1 2 2 2 2 1 2 1 ...
 $ Occupation                       : Factor w/ 4 levels "1","2","3","4": 3 3 2 2 2 2 2 2 1 1 ...
 $ No.of.dependents                 : Factor w/ 2 levels "1","2": 1 2 1 2 1 2 1 2 1 1 ...
 $ Telephone                        : Factor w/ 2 levels "1","2": 1 1 1 1 1 1 1 1 1 1 ...
 $ Foreign.Worker                   : Factor w/ 2 levels "1","2": 1 1 1 2 2 2 2 2 1 1 ...

在这里，我想对一个超过3个级别的因子变量进行热编码。

例如，Guarantors变量有3个级别1,2,3。因此，我想获得Guarantors1，Guarantors2和Guarantors3变量，这些变量只有0.1值作为data.frame。

Answer 1

dplyr＆amp; purrr方法

library(dplyr)
library(purrr)

german<-read.csv("http://freakonometrics.free.fr/german_credit.csv", header=TRUE)

cols <- c(1,2,4,5,7,8,9,10,11,12,13,15,16,17,18,19,20,21)

map_df(german[, cols], as.factor) %>% 
      select_if(function(x) nlevels(x) >= 2) %>% 
      model.matrix(~. -1, data = .) %>% 
      as.data.frame()

我建议您阅读帮助model.matrix或other questions from SO on this topic.

如何使用一个超过3级的热编码因子变量？

1 个答案: