Date: Mon, 2 Oct 2006 00:04:39 -0700
Reply-To: David L Cassell <davidlcassell@MSN.COM>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: David L Cassell <davidlcassell@MSN.COM>
Subject: Re: IVEWARE
In-Reply-To: <CBEHKHLADEBPHMJJBGAOOEBJELAA.msoobader@verizon.net>
Content-Type: text/plain; format=flowed
mah-j@statworks.com wrote:
>
>There seemed to be some folks out there asking about IVEWARE- so I'm hoping
>I can get some help with this.
>
>I have 3 types of 'count/continuous/mixed' variables - these are all
>non-negative integer values
>- in addition they all have legitimate skips- e.g.
>
>A- has values from 1 to 24.... (Count?)
>B- has values from 0 to 1000.....( should this be considered a count or
>continuous given the range?)
>C- has values from 0 to 100 with over 20% =0... ( Mixed?)
>
>I recall having some problem previously with B- about there being too many
>categories- if we regard B as continuous how will we deal with '0'- given
>legitimate skips are set to zero for continuous variables?
>
>Would I specify them in the impute program as follows:
>
>Default Categorical;
>Count A;
>Continuous B;
>Mixed C;
>
>Would I specify the bounds statement as follows e.g. A- is number of hours
>-
>so values should only be between 1 and 24.
>
>Bounds A (1 < 24) B (0 < 1000) C (0 <100)
>
>Will the legitimate skips be coded to one higher than the last value as
>follows:
>
>A-25
>B-1001
>C-101
>
>Thanks Mah-J
I don't think there's much IVEWARE help on this list, but I'll
do what I can.
You will have to look at the distributions for A and B and C and
decide if you want to treat them as count or continuous or mixed.
A range of 0 to 1000 may be any of the above. It depends on how
the data points look. If they only take on 10 different values (or 10
very tight clusters of values) then you may want to treat them as
dicrete. Similarly, the range of 24 may be spread well enough to treat
as continuous, particularly if the vairable itself is more meaningful and
interpretable as a continuous concept.
And don't forget to use multiple imputation instead of single
imputation.
HTH,
David
--
David L. Cassell
mathematical statistician
Design Pathways
3115 NW Norwood Pl.
Corvallis OR 97330
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