I would make sure that -xtile- -tab- and -cumul- treat weights in the
same way by specifying for each command [pw=my_weight]
Hope this helps,
Maarten
--- Mark Orr <[email protected]> wrote:
> Hello all,
>
> I'm using a national dataset for which the weights adjust for
> oversampling and some other factors. My goal is to make deciles of a
>
> variable, say var_x, but with taking the weighted empirical
> distribution
> as the basis for making the deciles. I've computed this three ways,
> but
> all with slightly different results. The code for the three
> different
> decile computations were as follows:
>
> 1.
> xtile var_x [wt=my_weight], nq(10)
>
> 2.
> tab var_x [wt=my_weight]
> THEN COMPUTE THE DECILES BY HAND BASED ON THE WGTED EMPIRICAL CDF
>
> 3.
> cumul var_x [wt=my_weight], gen(cdist)
> gen var_x_decile = ceil(10 * cdist)
>
> So, my method for comparing these was to compute the mean for each
> decile. I get three different (but) similar means for each
> computation
> type.
>
> Any thoughts. I'm stumped.
>
> Thanks very kindly. (i've checked the archives pretty well, but
> nothing
> that really explains what is going on here)
>
> -Mark Orr
>
> --
> ***********************************************
> Mark G. Orr, PhD
> Heilbrunn Dept. of Population and Family Health
> Columbia University
> 60 Haven Ave., B-2
> New York, NY 10032
>
> Tele: 212-304-7823
> Fax: 212-305-7024
>
> www.columbia.edu/~mo2259
>
> > begin:vcard
> fn:Mark G. Orr
> n:Orr;Mark G.
> org:Columbia University;Heilbrunn Department of Population and Family
> Health
> adr;dom:;;60 Have Ave., B2;New York;NY;10032
> email;internet:[email protected]
> title:Ph.D.
> tel;work:212-304-7823
> tel;fax:212-305-7024
> tel;home:718-414-5151
> url:http://www.columbia.edu/~mo2259
> version:2.1
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>
>
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room Z434
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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