Re: st: Creating a second output data set

[Roger Newson <r.newson@imperial.ac.uk>]

I think you are looking for the -postfile- utility. In Stata, type

help postfile

to find out more.

HTH.

Best wishes

Roger


Roger B Newson BSc MSc DPhil
Lecturer in Medical Statistics
Respiratory Epidemiology and Public Health Group
National Heart and Lung Institute
Imperial College London
Royal Brompton Campus
Room 33, Emmanuel Kaye Building
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UNITED KINGDOM
Tel: +44 (0)20 7352 8121 ext 3381
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Email: r.newson@imperial.ac.uk
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Opinions expressed are those of the author, not of the institution.

On 06/09/2011 21:53, Bryan Sayer wrote:
> I need to create an output data set that will differ in the content and
> number of observations from the input file. The observations will be
> created one at a time, based on the input data set.
>
> Specifically, I am creating all combinations of N objects taken two at a
> time. I will probably also do permutations.
>
> The input data set (to start with) consists of N records with two
> variables, the primary sampling unit (PSU) and a size variable
> associated with the PSU (a count variable). I want to create two output
> data sets. One is each combination of PSU with the associated joint
> probability. The second has the same structure as the input data set but
> includes the marginal probability, calculated as the sum of the joint
> probabilities associated with the PSU (which are accumulated as each
> combination is created).
>
> The part I am stuck on is how to output the data set of combinations.
> Can someone point me to a program that outputs a file as calculations
> are made?
>
> (For those interested, this is for probability proportional to size
> (PPS) sampling. See, for example, Levy and Lemeshow "Sampling of
> Populations, chapter 11).
>
> Here is an example of one stratum:
>
> Input data set (with marginal probability added)
>
> District Size pi(i)
> LUWEERO 12,466 0.916858
> KAMPALA 3,459 0.542857
> TORORO 2,815 0.448739
> KAMULI 549 0.091546
> Total 19,289
>
>
> Output data set:
>
> COMBINATIONS pi(I,j)
> LUWEERO,KAMPALA 0.468854
> LUWEERO,TORORO 0.377069
> LUWEERO,KAMULI 0.070934
> KAMPALA,TORORO 0.062531
> KAMPALA,KAMULI 0.011473
> TORORO,KAMULI 0.009139
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