st: MI: Multiple Imputation

[Shikha Sinha <shikha.sinha414@gmail.com>]

Hi,

I am using -mi for imputing the missing values. The variable is "edu"
has five categories (1=primary, 2=secondary, and so on...). I used the
following command:

mi register imputed edu
mi register regular age gender country
set seed 23456
mi impute mvn edu = i.gender age country, add (5)
mi estimate, or: logistic Y X1 X2 edu

After imputation, five new variables are generated, such as , _1_edu,
_2_edu, _3_edu, .......

Now, I have following questions:

(a) Why some observations have negative values for  _1_edu, _2_edu,
_3_edu, ........ Negative values for education doesnot make sense. How
to restrict this so that there is no negative values.

(b) How do we use the five new generated variable? Can I just run

logistic Y X1 X2 _1_edu

or

logistic Y X1 X2 _2_edu

(c) Can I create a dummy for primary or secondary schooling from the
imputed values _1_edu?

Thanks,
Shikha
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