有关在R中重新编码分类变量的问题

Question

Very green R user here. I have to categorical variables: One is, committee crime against child or has mental health issues (dichotomous, 1= crime and 0 = mental health) and committed crime against child or has substance abuse issues (dichotomous, 1= crime and 0 = substance abuse). I'd like to combine these groups so I will have a dichotomous, crime against child and mental health or substance abuse group. What would be the best way to do this? I have been playing around with "if" statements but to no avail.

I have been playing around with "if" statements but to no avail. I want to make a new variable in my dataset (com) that combines crime against child (1) and mental health/substance abuse (0)

x$com <- if(x$Group.finalCvsM == 1) {
  x$com("1") }
  if(x$Group.finalCvsS == 1) {
    x$com("1") }
  if(x$Group.finalCvsM == 0) {
    x$com("0") }
    if(x$Group.finalCvsS == 0) {
      x$com("0") }

Answer 1

Because your data is coded as binary 0/1, we can just use the logical OR operator, | .

## very nice way to solve this particular problem
x$com = x$Group.finalCvsM | x$Group.finalCvsS
## The result will be TRUE or FALSE. 
## If you want 1/0 instead, then wrap it in as.integer: 
x$com = as.integer(x$Group.finalCvsM | x$Group.finalCvsS)

In general , ifelse() is a vectorized version of if that is made for cases like this. See the help page ?ifelse for some detail. Here you would use it as:

x$com = ifelse(x$Group.finalCvsM == 1 | x$Group.finalCvsS == 1, 1, 0)

( Note:: since your question doesn't give sample input and desired output, I'm not 100% sure you want OR | . Maybe you want & ? Both work fine, use whichever meets your goal.)