--- On Fri, 8/5/09, Gianluca Cafiso wrote:
> I need to test if the concentration index (CI) for a sample
> of geo-units has changed over time trough a bootstrap
> procedure. <snip> (as done in Brulhart+Traeger 2005).
>
> To compute the index, I have used the "ineqdeco"
> routine separately on the Employment variable for t1 and then
> on the one for t2.
>
> However, I do not know how to implement the bootstrap test.
<snip>
Please give full references, and not just a author/year reference.
This is discussed in the Statalist FAQ.
I don't know if this makes sense, I am no expert on these inequality measures, but the general strategy is to collect the different
models in one program and return the statistic of interest:
*---------- begin example ----------------
sysuse auto, clear
capture program drop bootdiff
program define bootdiff, rclass
tempname for
sum mpg if foreign == 1, meanonly
scalar `for' = r(mean)
sum mpg if foreign == 0, meanonly
return scalar diff = `for' - r(mean)
end
bootstrap diff=r(diff), reps(100):bootdiff
*---------- end example --------------------
-----------------------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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