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

Stata 11 Sample Session Section 3 – Tables and other Types of Analysis
Converting categorical variables to
indicator variables
generate byte age18p = ca3>=18 if ca3 < .
tab1 age18p
Then, any missing values in ca3 would also be missing in
the new variable age18p.
Suppose that you want to do regression analysis and control
for effects of the different geographic regions. We have a
variable called district which has 3 categories. We want to
create indicator variables for the three districts. These
types of variables are also called dummy variables. First
let’s run the describe command to look at the contents of
the file:
describe
Next let’s look at the values and labels for the variable
district:
label list district
To make 3 indicator variables we can type:
tabulate district, generate(district)
Now, run the describe command again:
describe
Three new variables have been created, called district1,
district2, and district3. We can examine the variables using
the tab1 command.
tab1 district*
The variables district1, district2, and district3 can now be
used for regression analysis as dummy variables. They
contain either a 0 or a 1.
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