Hi. I'm not exactly sure what the context is, but here are a couple of things...
If in your SPSS Data Editor you see "." in some cells (we call those "sysmis" or system-missing values) and you want them to be -99 and defined as missing, try
RECODE <whatever variables> (SYSMIS=-99).
MISSING VALUES <whatever variables> (-99).
If you have actual values that you want to change to -99 and then define as missing, then try
RECODE <whatever variables> (<arg>=-99).
MISSING VALUES <whatever variables> (-99).
where <arg> can be a variety of things, like:
1. LO THRU HI
2. LO THRU <some number>
3. <some number> THRU HI
4. <some number> THRU <some other number>
5. <some list of values, from 1 value to a series of them>
etc.
or even certain combinations of these, depending on what the need is.
Finally, I have also used the SYSMIS function on the IF command:
IF SYSMIS(<some variable>) <some variable> = -99.
MISSING VALUES <some variable> (-99).
You can find details on IF, RECODE, SYSMIS, and MISSING VALUES in the Command Syntax Reference.
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Rick Marcantonio
Quality Assurance
IBM
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