RE: st: smart averaging

[Nick Cox <n.j.cox@durham.ac.uk>]

That can be done in various ways. Here is one: 

bys id : egen OK = total(inrange(year,2006,2009) & income < .) 

by  id: egen average_inc = mean(income / (OK == 4))

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

Fernando Rios Avila

If you are trying to average it only for those without missing
variables, the easier process could be:
1. identify number of missing observations by id
2. average for all
3. replace by missing value if the number of missing values is higher than 0


On Wed, Feb 22, 2012 at 7:54 PM, Murat Mercan <mamercan@gmail.com> wrote:

> I have the following problem I have been unable to decipher. I have the
> following data set:
> id      year       income
> 1       2006      100
> 1       2007      50
> 1       2008       .
> 1       2009       .
> 2       2006       50
> 2       2007       50
> 2       2008       50
> 2       2009       50
> I want to average the income variable for those four years. I tried to use
> the following command:
>
> bys  id: egen average_inc = mean(income) if inrange( year,2006,2009)
>
> However, that averages person 1's income, too. I need to average just
> person 2's income.

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