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

Stata 11 Sample Session Section 2 – Restructuring Data Files – Table Lookup & Aggregation
Calculate the total calories
produced
done:
tab1 _merge
Note that there are 87 cases with no value in the calorie
variable. How would you check to see which products
have no calorie value?
We can now compute total calories produced.
1. Select Create or change variables from the
Data menu
2. Select Create new variable
The Generate – Create a new variable dialog box
opens. We have used this dialog box earlier.
To clear the contents, click on the “Reset”
icon in the lower left corner of the dialog
box.
3. Under the Main tab, change the Variable type
to “double”.
4. Type the name of the new variable in the
Variable name box: cprod_tt
5. For the Contents of new variable box, type in
qprod_tt * calories
6. Click on the copy button, switch to the do-file
editor, paste the command, switch back to the
dialog box and click on Ok
7. Add a comment in the do-file to explain what
you have done.
The Stata command is:
generate double cprod_tt= qprod_tt * calories
Note that missing values were generated for 131 cases.
Assign variable labels The two new variables do not yet have variable labels.
To assign a variable label:
1. Click on Data, then Data utilities, then Label
utilities, then Label variable.
2. In the Variable: box, select the name of the first
variable: qprod_tt
3. In the New variable label (may be up to 80
characters) box, type
Total production in kgs
4. Click on the copy button, switch to the do-file
editor, paste the command, switch back to the
dialog box and click on the Submit button.
Clicking on the “submit” button leaves the
dialog box open so we can then define the
label for the cprod_tt variable without having
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