st: Multivariate imputation using chained equations

["Jacqueline Jodl" <jmj2138@tc.columbia.edu>]

I am attempting multivariate imputation using chained equations. 

My longitudinal dataset (NLSY79) codes the missing data that I wish to
impute as -1, -2, and -3 (don't know, refusal, and invalid skip,
respectively). The data that I do NOT want to impute is coded at -4, -5, and
-7 (noninterviews and valid skips). 

I have included the following in my syntax to account for the observations
that I wish to impute:

ds*
     local allvars = r(varlist)
     foreach var of local allvars {
        replace `var' = . if `var' == -1 | `var' == -2 | `var' == -3
     }

Is there a similar approach to including syntax that excludes the data
points coded as -4, -5, and -7?

Thanks, 
Jacqueline Jodl
Teachers College 
Columbia University
New York, New York

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