Stata The Stata listserver
[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

st: RE: Re: help creating a unique identifier


From   "Nick Cox" <n.j.cox@durham.ac.uk>
To   <statalist@hsphsun2.harvard.edu>
Subject   st: RE: Re: help creating a unique identifier
Date   Thu, 17 Mar 2005 17:37:26 -0000

As flagged by Michael, there are several FAQs 
relevant to this kind of manipulation. 

How do I create individual identifiers numbered from 1 upwards? 
http://www.stata.com/support/faqs/data/group.html

How do I create a variable recording whether any members 
of a group (or all members of a group) possess some 
characteristic? 
http://www.stata.com/support/faqs/data/anyall.html

Nick 
n.j.cox@durham.ac.uk 

Michael Blasnik
 
> A similar question was recently asked and FAQ certainly 
> addresses the unique 
> identifier, but here are some answers:
> 
> egen SeqId=group(id_dom)
> 
> or
> 
> sort id_dom age
> gen SeqId=sum(id_dom!=id_dom[_n-1])
> 
> for your second question, if there are no missing values on 
> age, then this 
> works:
> 
> bysort id_dom (age): gen byte hasover15=age[_N]>=15
> 
> otherwise, the easiest approach may be:
> 
> egen maxage=max(age),by(id_dom)
> gen byte hasover15=maxage>15 if maxage<.

Joao Pedro Wagner de Azevedo

> > I have a dataset with the variable id_dom (numeric) which s a unique
> > identifier of households and the variable age (see extract 
> below). I would
> > like to create a couple of new variable and I would 
> sincerely appreciate 
> > if
> > anyone on the list give me a hand.
> >
> > First, I would like to create a sequential unique identifier such as
> > variable SeqID. Second, I would like to create a variable 
> which would flag
> > all those households with at least on adult (age>=15).
> >
> > Initially I would like to avoid having to use collapse and 
> merge (given 
> > the
> > size of my dataset), and I have been trying to use command 
> such as bysort,
> > _n and _N.
> >

*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/



© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index