Re: st: question about weights in histograms

[Steven Joel Hirsch Samuels <sjhsamuels@earthlink.net>]

Good call, Austin! All multiples of the original weight will give the  
same result for means and percentages.

-Steve
On Oct 10, 2007, at 12:44 PM, Austin Nichols wrote:


> Or, better, multiply the weight by the reciprocal of the smallest
> increment ("units" in -codebook- output) and use that as a frequency
> weight, which should give you identical point estimates to -svy-
> output:
>
> use hhinc mars using cpsmar07
> g double wt=round(marsupwt*100)
> hist hhinc [fw=wt], xscale(log) percent
>
> On 10/10/07, Steven Joel Hirsch Samuels <sjhsamuels@earthlink.net>  
> wrote:
>
> > Round the weights to the nearest integer and use these as frequency
> > weights.  -histogram- is not a survey command and so is unaffected by
> > -svyset-.   The results will be nearly identical to  what you would
> > get if you estimated  the per cent in each category using -svy:
> > proportion-.  By the way, in most complex surveys the weights have
> > been trimmed to reduce total error: bias^2 + se^2.  So you cannot
> > expect 'unbiased' estimates even with the original weights.
> >
> > -Steve
> >
> > On Oct 10, 2007, at 12:02 PM, Scott Cunningham wrote:
> >
> > > I am using 5% Census and March CPS data (United States) to construct
> > > histograms.  These data include probability weights.  I know that
> > > histogram can adjust for frequency weights, but apparently not
> > > explicitly for probability weights that are not integers.  If I
> > > -svyset- the data using the perweight, will -histogram- construct
> > > unbiased estimates of the population?  Here is my code
> > >
> > > . svyset [perweight=perwt]
> > > . histogram tax, by(white, col(1)) percent
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Steven  Samuels

sjhsamuels@earthlink.net
18 Cantine's Island
Saugerties, NY 12477
Phone: 845-246-0774
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