Re: st: set seed and gsample

[Richard Williams <Richard.A.Williams.5@ND.edu>]

At 05:58 PM 3/7/2007, ��� wrote:
> Dear All,
>
> I am trying to draw a PPS sample using the "gsample" command.  I want
> to make sure I get the same sample each time I invoke the gsample
> command by using the "set seed" command. However, even after I set the
> random seed using "set seed" command, I still get different sample
> each time. Has anybody encountered this problem? Thanks!
>
> Best,
> Shige
Like Nick says, we'll need to see the commands; 
and better yet would be a reproducible 
example.  Here is an example of where it works fine:

. webuse auto, clear
. gen id = _n
. set seed 123
. gsample 10
(1 observation created)
(65 observations deleted)

. list id

     +----+
     | id |
     |----|
  1. | 68 |
  2. |  1 |
  3. | 21 |
  4. | 35 |
  5. | 42 |
     |----|
  6. | 50 |
  7. | 46 |
  8. | 65 |
  9. |  1 |
 10. | 31 |
     +----+

. webuse auto, clear
. gen id = _n
. set seed 123
. gsample 10
(1 observation created)
(65 observations deleted)

. list id

     +----+
     | id |
     |----|
  1. | 68 |
  2. |  1 |
  3. | 21 |
  4. | 35 |
  5. | 42 |
     |----|
  6. | 50 |
  7. | 46 |
  8. | 65 |
  9. |  1 |
 10. | 31 |
     +----+



-------------------------------------------
Richard Williams, Notre Dame Dept of Sociology
OFFICE: (574)631-6668, (574)631-6463
HOME:   (574)289-5227
EMAIL:  Richard.A.Williams.5@ND.Edu
WWW:    http://www.nd.edu/~rwilliam


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