# Re: st: bootstrapping

 From "Vincenzo Carrieri" To statalist@hsphsun2.harvard.edu Subject Re: st: bootstrapping Date Fri, 11 Jul 2008 11:20:46 +0200

```Thanks Maarten,
but expand command just duplicate each observation.It's not a random
resampling.
Do you think could be enough to make a bit of inference on my proportion?

Vincenzo

2008/7/10 Maarten buis <maartenbuis@yahoo.co.uk>:
> 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
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>
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>
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*
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```