First off - let me say I joined this list about 2 weeks ago- and am enjoying
the stimulating discussions. Its so often that we not able to keep up with
SAS- and the dynamic, spirit and advice that is being provided by the guru's
on this list is awesome. Great work!!!
Thank you David for your sound advice. I have some familiarity with survey
data (only been at it for
about 10 years now ;))- I'm going with IVEWARE- because it is a really good
imputation program- and also the National Center for Health Statistics used
it for their income imputations for the National Health Interview Survey-
and the survey I'm working is the child component of that- so there is some
I'm only a recent convert to imputation.
From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU]On Behalf Of
David L Cassell
Sent: Tuesday, November 29, 2005 3:39 PM
Subject: Re: removing ?formatted missing values
>I'm working with a national survey that has the missing values set as .L
>.M- (I'm not sure whether this is some kind of a format as these show up as
>. missing in frequencies etc.)- is there a general statement that I can use
>to remove these from the 100+ variables in the dataset- such as format
>for real formats?
>The reason I need to do this is that I'm running an imputation using
>(SAS callable procedure)- and for some reason- this program doesn't like
>.L and .M's
>ps: Any users of IVEWARE on this list- willing to humor a few questions?
 If you have a "national survey", I hope you're going to use survey
methods for analysis. Since you're working with IVEware, I assume you have.
 You can use PROC MI in SAS 9 for multiple imputation as well, and then
you can get more help from this list. PROC MI *does* know how to handle
what we call "special missing values".
 The purpose of special missing values is to provide additional
the user. It's not only a missing value, it's also a floorwax! Sorry, I
the old SNL joke. It is not only a missing value, it is also a descriptor
for the cause
of the missing-ness, or the consequences of the missing-ness. So look up
meaning of these special missing values, because they may need to be treated
differently than other missings. That may impact the imputation, as well as
 You can always ask IVEware quesitons here. You may not find anyone
good answer, but you can ask...
David L. Cassell
3115 NW Norwood Pl.
Corvallis OR 97330
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