How to recode into new variable in STATA

To recode variables in Stata, use the recode command. To use recode, you must provide a list of variables to be recoded and the rules associated with that change.
For a variable (e.g., q1) that contains integers ranging from 1 to 7, to collapse the values into three categories, use:
 recode q1 1=1 2=1 3/5=2 6=3 7=3
In the example above:
  • The values of 1 and 2 are recoded as 1. 
  • The values of 3, 4, 5 are recoded as 2.
    Note:
    The forward slash (/) denotes a range of values (e.g., from 3 to 5), including the beginning and end of the range. 
  • The values of 6 and 7 are recoded as 3. 
After using recode, you cannot recover the original values. To recode and store changes into a new variable (e.g., new_q1), combine recode with the gen() option:
 recode q1 1/2=1 3/5=2 6/7=3, gen(new_q1)
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