How do you convert Categorical Variables to dummy variables in SAS?
To generate the dummy variables, put the names of the categorical variables on the CLASS and MODEL statements. You can use the OUTDESIGN= option to write the dummy variables (and, optionally, the original variables) to a SAS data set.
How do I recode a value in SAS?
To recode values in a data set:
- Select the input data source.
- Specify whether you are recoding values for a numeric or character variable.
- Assign the variable whose values you want to change to the Variable to recode role.
- Specify a name for the variable that contains the recoded values.
What does it mean to create dummy variables in SAS?
Create dummy variables in SAS. The word “dummy” does not imply that these variables are not smart. Rather, dummy variables serve as a substitute or a proxy for a categorical variable, just as a “crash-test dummy” is a substitute for a crash victim, or a “sewing dummy” is a dressmaker’s proxy for the human body.
What to use if SAS does not support class statement?
If a SAS procedure does not support a CLASS statement, you can use often use dummy variables in place of a classification variable. An example is PROC REG, which does not support the CLASS statement, although for most regression analyses you can use PROC GLM or PROC GLMSELECT.
When to use a design matrix in SAS?
However, it can be useful to create a SAS data set that explicitly contains a design matrix, which is a numerical matrix that use dummy variables to represent categorical variables. A design matrix also includes columns for continuous variables, the intercept term, and interaction effects.
When to use a dummy variable in regression?
In regression and other statistical analyses, a categorical variable can be replaced by dummy variables. For example, a categorical variable with levels “Low,” “Moderate,” and “High” can be represented by using three binary dummy variables.