STATA 11 for Windows SAMPLE SESSION - Food Security Group ...

Stata 11 Sample Session Section 2 – Restructuring Data Files – Table Lookup & Aggregation
to select it again from the menus.
5. In the Variable: box, select the name of the
second variable: cprod_tt
6. In the New variable label (map be up to 80
characters) box, type
Total calories produced
7. Click on the copy button, switch to the do-file
editor, paste the command, switch back to the
dialog box and click on the Ok button.
8. Add a comment to the do-file to explain what
you have done.
The Stata commands are:
label variable qprod_tt "Total production in kgs"
label variable cprod_tt "Total calories produced"
This gives us a new working data file with total calories
produced per product for each household.
Select only staple food products The final output table asks only for information about the
staple food crops. These are defined as:
peanuts (prod=5))
rice (prod=6)
nhemba bean (prod=30)
manteiga bean (prod=31)
manioc (prod=41)
sorghum (prod=44)
maize (prod=47)
We can find the product code by looking at prod in the
questionnaire. Since we are only interested in those
products, we need to exclude the rest of the cases about
other crops. Stata uses the “keep” command. Once you
run this command you will no longer have the complete
data set available. You must remember that you should
never save a file to the same name after you have selected
out a set of data. You will overwrite the original data and
no longer have the complete set.
The keep if command To select just a subset of cases:
1. Click on Data, then Create or change
variables, then Keep or drop observations.
You should see the drop - keep or drop
observations dialog box.
2. Under the Main tab select the round button next
to Keep Observations
3. In the Observations to keep if: box type
prod == 5 | prod == 6 | prod == 30 |
prod == 31 | prod == 41 | prod ==44 |
prod == 47
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