Mmm ..random number generation is a massive subject 
never too far from a practitioners mind, is it.
Its always attached to a question mark with me.
Full marks are surely due to the wizards behind the reseach.
In one sentence or two, do you know, please what tests are 
used to demonstrate randomness
of the output observations ?
Just asking, is all.
Thanks everybody

Best regards from Richard Hudson

Dr RJF Hudson Qld Australia 
rjfhud(a)powerup.com.au

  ----- Original Message ----- 
  From: Allin Cottrell 
  To: Gretl users 
  Sent: Saturday, January 15, 2011 2:12 AM
  Subject: [Gretl-users] the gretl RNG


  For some years now the random number generator (RNG) used in gretl
  has been the Mersenne Twister as implemented in the GLib library.

  We've recently been investigating an alternative, namely the
  SIMD-oriented Fast Mersenne Twister (SFMT); see

  http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/SFMT/

  We find that this new variant is faster, has better
  equidistributional properties, and exhibits quicker recovery from
  poor initialization. We're therefore going to make SFMT the
  default RNG in gretl: this will be in the next release (gretl
  1.9.4) and will land in CVS and the snapshots for Windows and Mac
  shortly.

  This change is (necessarily) backward incompatible, in the sense
  that a gretl script that calls for random values using a specified
  seed will now produce a different series of random values from
  before. However, to preserve compatibility for anyone who wants to
  replicate previous studies exactly, you will be able to call for
  use of the old gretl RNG. The command to do this will be

  set RNG MT

  Having done that, you can switch back to the new default via

  set RNG SFMT

  Allin Cottrell





  _______________________________________________
  Gretl-users mailing list
  Gretl-users(a)lists.wfu.edu
  http://lists.wfu.edu/mailman/listinfo/gretl-users
Mmm ..random number generation is a massive subject
never too far from a practitioners mind, is it.
Its always attached to a question mark with me.
Full marks are surely due to the wizards behind the reseach.
In one sentence or two, do you know, please what tests are
used to demonstrate randomness
of the output observations ?
Just asking, is all.
Thanks everybody
 
Best regards from Richard Hudson
 
Dr RJF Hudson Qld Australia
rjf...@powerup.com.au
----- Original Message -----
Sent: Saturday, January 15, 2011 2:12 AM
Subject: [Gretl-users] the gretl RNG

For some years now the random number generator (RNG) used in gretl
has been the Mersenne Twister as implemented in the GLib library.

We've recently been investigating an alternative, namely the
SIMD-oriented Fast Mersenne Twister (SFMT); see

http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/SFMT/

We find that this new variant is faster, has better
equidistributional properties, and exhibits quicker recovery from
poor initialization. We're therefore going to make SFMT the
default RNG in gretl: this will be in the next release (gretl
1.9.4) and will land in CVS and the snapshots for Windows and Mac
shortly.

This change is (necessarily) backward incompatible, in the sense
that a gretl script that calls for random values using a specified
seed will now produce a different series of random values from
before. However, to preserve compatibility for anyone who wants to
replicate previous studies exactly, you will be able to call for
use of the old gretl RNG. The command to do this will be

set RNG MT

Having done that, you can switch back to the new default via

set RNG SFMT

Allin Cottrell





_______________________________________________
Gretl-users mailing list
gretl-us...@lists.wfu.edu
http://lists.wfu.edu/mailman/listinfo/gretl-users

Reply via email to