re: st: Taking averages, etc.

[David Airey <david.airey@vanderbilt.edu>]

Stata ignores missing observations when calculating the mean:

. list, mean

      +---------+
      | average |
      |---------|
   1. |       4 |
   2. |       . |
   3. |       4 |
   4. |       4 |
      |---------|
 Mean |       4 |
      +---------+

Sometimes, you do have to be careful to use "if e(sample)". For 
example, if you wanted to compute model yhats on just those 
observations used in the model.

-Dave


> Hello, everyone!
>
> Can anyone tell me if it's possible to tell Stata to ignore missing
> observations when computing averages, etc.? I think that if there is a
> missing value in the observations considered, the average computed 
> would
> be then missing too... and I need it to intelligently choose how many
> observations to use depending on whether observations are available,
> etc.
>
> Thanks!
> Adrian
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