st: Is a simple dummy imputation a valid procedure?

[Andrea Bennett <mac.stata@gmail.com>]

Hi!

I know there are more advanced methods to deal with missing data (ICE or mi). But if one is not interested in the variable containing missing values per se and only wants to include this variable as an additional control because the distribution of missing values of this particular variable is not quite equal between a control and a treatment group, is it then ok to use the median income of students in the same class and impute this value where a students income is missing, add a dummy for where there was a missing value and interact the two?

I just think it is important not to simply drop observations where we observe missing values when they are not equally distributed across groups. But I am somewhat hesitant to apply methods I do not really understand. Also, using the simple dummy imputation seems ok since I strongly suspect the same motives behind not responding to this particular question.

Many thanks for your suggestions,

Andrea


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