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Disadvantages of Seed 0

Posted By: Maik Stiebler
Date: Monday, 20 February 2012, at 7:22 a.m.

In Response To: Disadvantages of Seed 0 (Taper_Mike)

In order to combine two rollouts, their seeds must be different. Even then, the process is problematic, because two rollouts are not independent unless the entire sequence of random dice rolls used in one does not overlap any part of the sequence used in the other. Specifically, if the two random dice sequences overlap in such a way that rolls are repeated starting from the first turn of a game, then the trials from that point on are not independent.

I don't know a thing about how Extreme Gammon creates its random numbers, but I would think that that is not a problem with good random number generators. Different seed means overlapping is ridiculously unlikely, unless our typical number of trials expands to 10^30 or something, or the seeding is done in a particularly unfortunate way.

Some suggest that when both rollouts use the seem seed, variance is lessened. I am not so certain myself.

I am not certain either. I believe that the effect is negligible if variance reduction is used. Also, what Xavier said here means that seeds will only be the same if the displayed seeds match AND the positions are the same.

Messages In This Thread

• 61P-31P-33
  Paul Weaver -- Saturday, 5 February 2011, at 4:50 a.m.
  • 61P-31P-33
    neilkaz -- Saturday, 5 February 2011, at 5:01 a.m.
  • 61P-31P-33
    Lucas Bauer -- Saturday, 5 February 2011, at 5:04 a.m.
  • 61P-31P-33, weak bot content
    Nack Ballard -- Saturday, 5 February 2011, at 5:53 a.m.
    • Nactations of 61P-31P-33 — Y (Yoga split) Family
      Taper_Mike -- Saturday, 17 December 2011, at 6:28 a.m.
      • Nactations of 61P-31P-33 — Y (Yoga split) Family — Correction
        Taper_Mike -- Saturday, 17 December 2011, at 6:53 a.m.
        • Nactations of 61P-31P-33 — Y (Yoga split) Family — Correction
          Nack Ballard -- Saturday, 17 December 2011, at 8:22 a.m.
          • Nactations of 61P-31P-33 — Y (Yoga split) Family — Correction
            Taper_Mike -- Saturday, 17 December 2011, at 9:11 a.m.
  • 61P-31P-33
    Dmitriy Obukhov -- Saturday, 5 February 2011, at 7:10 a.m.
    • When To Post Rollout Result
      Paul Weaver -- Saturday, 5 February 2011, at 4:34 p.m.
  • 61P-31P-33
    Casper van der Tak -- Saturday, 5 February 2011, at 8:14 a.m.
  • 61P-31P-33
    Sam Pottle -- Saturday, 5 February 2011, at 9:17 a.m.
  • Correct Play in Related 65R-61P-31P-33 is Different
    Paul Weaver -- Saturday, 5 February 2011, at 4:36 p.m.
    • 61P-31P-33, 65R-61P-31P-33, and twin variants
      Nack Ballard -- Sunday, 6 February 2011, at 1:48 a.m.
      • 61P-55P-33 Rollout Result Posted
        Paul Weaver -- Sunday, 6 February 2011, at 4:18 p.m.
  • Three Rollout Results Posted
    Paul Weaver -- Sunday, 6 February 2011, at 3:36 a.m.
  • ALT *RO* 61P-31P-33
    Dmitriy Obukhov -- Monday, 7 February 2011, at 5:32 a.m.
    • ALT *RO* 61P-31P-33
      Nack Ballard -- Monday, 7 February 2011, at 6:12 a.m.
      • ALT *RO* 61P-31P-33
        Nack Ballard -- Monday, 7 February 2011, at 6:50 a.m.
        • ALT *RO* 61P-31P-33
          Dmitriy Obukhov -- Monday, 7 February 2011, at 7:05 a.m.
          • Disadvantages of Seed 0
            Taper_Mike -- Saturday, 18 February 2012, at 9:05 a.m.
            • Disadvantages of Seed 0
              Petter Bengtsson -- Saturday, 18 February 2012, at 9:25 a.m.
              • Disadvantages of Seed 1
                Taper_Mike -- Saturday, 18 February 2012, at 9:43 a.m.
                • Seed
                  Nack Ballard -- Saturday, 18 February 2012, at 4:36 p.m.
            • Disadvantages of Seed 0
              Maik Stiebler -- Monday, 20 February 2012, at 7:22 a.m.
              • Disadvantages of Seed 1
                Taper_Mike -- Monday, 20 February 2012, at 8:08 a.m.
      • Nactation Update: R-Run must land between 17pt and 13pt
        Taper_Mike -- Monday, 24 October 2011, at 5:10 a.m.
        • Nactation Update: R-Run must land between 17pt and 13pt
          Nack Ballard -- Monday, 24 October 2011, at 6:01 a.m.