Sometimes the data that you have is not what is needed for your analysis.
For example, you may have the answers given to a number of questions, but what
you need to know whether these answers are
correct or not.
You need to change this data to reflect the correct answers. This is
done through data transformation.
Data Transformation:
compute
You can use the compute command to transform data. To do this, you must first name a target variable. Then you must specify the conditions necessary to change the data. For example, if you wanted to score a question, you would make your variable equal to 1, if the question was answered correctly. However, this only gives you a transformation for the correct answer - it leaves all the incorrect answers as blanks. Therefore, you must go back to the compute command to enter that your variable is equal to 0, if the question is answered incorrectly. This transformation takes two steps using the compute command.
Data Transformation: recode into a different variable
Recoding into a different variable is much faster, the transformation can be
done all in one step. First, you must choose the variable which you are
recoding and name the output variable which will hold your new value.
Next, you type in the old value and new values. This can be done as many
times as necessary to cover all the values of the variable. However, you
don't need to type all these values separately, you can use statements, such as
"all other values" or you can define a range that you want to recode
into a single value.
Data Transformation:
recode into the same variable
Recoding into the same variable is
not really much different from recoding into different variables. Again you choose the variable which you are recoding.
Again, you would type in old values and new values. When you press
continue, your new values replace the old values.