# Re: st: bootstrapping

 From Maarten buis To statalist@hsphsun2.harvard.edu Subject Re: st: bootstrapping Date Thu, 10 Jul 2008 21:04:32 +0100 (BST)

```I would do the following before starting to mess with stuff like the
bootstrap:

expand nnoti
proportion esenti

-- Maarten

--- Vincenzo Carrieri <vincenzo.carrieri@gmail.com> wrote:
> I have the following stata output:
>
> > esenti = 0
>
>     Variable |       Obs        Mean    Std. Dev.       Min
> Max
> ______________________________________________________
>       nnotti |      1032    4.545543    4.936243          1
> 80
>
> -> esenti = 1
>
>     Variable |       Obs        Mean    Std. Dev.       Min
> Max
> __________________________________________________________
>       nnotti |      3125     9.78528    12.73163          1
> 90
>
>
> "Esenti" is a dummy variable that indicates if a person copayment
> free
> or not. "nnotti" are the numbers of days spent in a hospital.
> So, the total number of nights, are 1032 (Obs)  x 4.545543 + 3125 X
> 9.78528 = 35270
>  I wish to calculate the proportion of nights spent by esenti=1 out
> of
> total nights. I compute simply this proportion, but It's just a
> sample
> proportion. Is it meaningful to randomly replicate my sample 1000
> times and compute my proportion for each of these samples? It allows
> me to have a range of values of my proportion and not only a single
> sample value. I think this should be bootstrapping, but I don't have
> a
>
> I appreciate any advice or comment.
> Many thanks,
>
> Vincenzo
> *
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>

-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands

Buitenveldertselaan 3 (Metropolitan), room Z434

+31 20 5986715

http://home.fsw.vu.nl/m.buis/
-----------------------------------------

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