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

Stata 11 Sample Session Section 2 – Restructuring Data Files – Table Lookup & Aggregation
1. From the Data menu select Create or change
variables then Other variable transformation
commands then Make dataset of means,
medians, etc.
The collapse - Make dataset of means, medians, etc.
dialog box will appear.
2. On the Main tab in the Statistics: box for 1:
change “mean” to “sum” by clicking on the dropdown
arrow. In the Variables: box select ae .
3. Click on the Options tab and in the Grouping
variables box, select district vil hh in that order
because those variables represent the identification
of an individual household.
The Grouping variable(s) is used to specify the variables to
be used for combining cases in the collapsed file. Any cases
from the original file that have identical values for all 3 of
the grouping variables will be combined into a single case in
the collapsed file. We want the collapsed file to have one
case per household, so we use the variables that identify a
household in our survey—district, vil, and hh.
4. Click on the copy button, switch to the do-file
editor, paste the command, switch back to the
dialog box and click on Ok
5. Add a comment in the do-file to explain what you
have done.
The Stata command is
collapse (sum) ae, by(district vil hh)
Collapse creates a new working file. The new working
data file is at the household level, with one case per
household. The variable ae is the total adult equivalents
for that household. Look at the resulting file (click on the
Data Browser tool). You should see four variables with
only one case per household. You can also look at the
variable definitions using the describe command. The
computed variable ae does not have a very descriptive
label any more so we need to change the label to reflect
what the variable is.
1. Click on Data, then Data utilities, then Label
utilities, then Label variable.
2. In the Variables: box, select the name of the first
variable: ae
3. In the Attach label to variable (up to 80 characters)
box, type
Adult equivalents per household
4. Click on the copy button, switch to the do-file
editor, paste the command, switch back to the
dialog box and click on Ok
71