How to treat numerical values as categorical values in CEM?

[Tracy Yang]

In my data, I have a variable of income level, which is 1,2,3,4,5,6,7, 8, and 9. I am wondering if I directly put this variable in

imb

or

cem

without recoding as illustrated in the manual, will the algorithm treat is as numerical value or categorical value?

Or shall I do recoding like this

recode income (1 = 1 "1") (2 = 2 "2") (3 = 3 "3") (4 = 4 "4") (5 = 5 "5") (6 = 6 "6") (7 = 7 "7") (8 = 8 "8") (9 = 9 "9"), gen(income_recode)

Thanks