--- On Tue, 17/11/09, Lachenbruch, Peter wrote:
> My inclination is NOT to use imputation - you already know
> these are below the detection limit, so why impute something
> larger than that?
Alternatively, you could use multiple imputation, as long as
your imputation model respects this information you have
about your variable. This is the kind of problem Patrick
Royston seems to had in mind when writing this update to his
-ice- command:
Patrick Royston (2007) Multiple imputation of missing values:
further update of ice, with an emphasis on interval censoring.
The Stata Journal, 7(4):445-464.
http://www.stata-journal.com/article.html?article=st0067_3
Hope this helps,
Maarten
--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany
http://www.maartenbuis.nl
--------------------------
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