How to replace words in a dichotomous column for an R data frame with numbers?\\n

A dichotomous column can be represented by words such as Yes/No, Good/Bad, Right/Wrong etc. To replace such words with number, say 1 and 0 we can use ifelse function.

For example, if we have a data frame called df that contains a column Binary with Yes and No values then we can replace Yes with 1 and No with 0 by using the below command −

df$Binary<-ifelse(df$Binary=="Yes",1,0)

Example 1

Following snippet creates a sample data frame −

x<-sample(c("Yes","No"),20,replace=TRUE) df1<-data.frame(x) df1

The following dataframe is created −

    x 1  Yes 2  Yes 3  Yes 4  Yes 5   No 6  Yes 7  Yes 8  Yes 9  Yes 10 Yes 11 Yes 12  No 13 Yes 14  No 15  No 16 Yes 17  No 18 Yes 19 Yes 20 Yes

To replace words Yes with 1 and No with 0, add the following code to the above snippet −

x<-sample(c("Yes","No"),20,replace=TRUE) df1<-data.frame(x) df1$x<-ifelse(df1$x=="Yes",1,0) df1

Output

If you execute all the above given snippets as a single program, it generates the following output −

   x 1  1 2  1 3  1 4  1 5  0 6  1 7  1 8  1 9  1 10 1 11 1 12 0 13 1 14 0 15 0 16 1 17 0 18 1 19 1 20 1

Example 2

Following snippet creates a sample data frame −

y<-sample(c("Good","Bad"),20,replace=TRUE) df2<-data.frame(y) df2

The following dataframe is created −

   y 1  Bad 2  Bad 3  Bad 4  Good 5  Good 6  Good 7  Good 8  Bad 9  Bad 10 Bad 11 Bad 12 Bad 13 Good 14 Bad 15 Good 16 Good 17 Good 18 Bad 19 Good 20 Good

To replace words Good with 1 and Bad with 0, add the following code to the above snippet −

y<-sample(c("Good","Bad"),20,replace=TRUE) df2<-data.frame(y) df2$y<-ifelse(df2$y=="Good",1,0) df2

Output

If you execute all the above given snippets as a single program, it generates the following output −

   y 1  0 2  0 3  0 4  1 5  1 6  1 7  1 8  0 9  0 10 0 11 0 12 0 13 1 14 0 15 1 16 1 17 1 18 0 19 1 20 1