Questions on Stata command terminology

[Hasanin Sanim]

If my indepvar is agegroup and have been categorized

• 31 to 40,
• 41 to 51
• 60 above

1. What is the subcategory or the bullet points in Stata language?
2. What is varlist and how is it made?
3. Is this command the right command I am trying to find out tobacco users in age sex etc in urban and rural regions?

proportion indepvar if depvar==1, over (region)

can depvar be placed after indepvar?