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At what point do you end a roll out.

Posted By: Timothy Chow
Date: Thursday, 24 May 2018, at 12:21 a.m.

In Response To: At what point do you end a roll out. (Joseph Pregler)

Happened to be driving by BGO today and saw this.

The guiding principle that you should follow is: Ignore the confidence percentage (58.1% in your case). It is never of any importance. I repeat: never.

Pay attention only to the size of the confidence interval (0.009 in your case if I'm reading you correctly). If it's small, and if you've rolled out a reasonable number of games, then that's enough. "Small" and "reasonable" are subjective but I'd say that for checker-play decisions, less than 0.010 is certainly small and less than 0.015 is probably small enough. For cube decisions I might double those numbers. And 1296 trials is certainly "reasonable" and half that may be reasonable for simple positions.

I recommend the book The Cult of Statistical Significance for more discussion of this issue.

Messages In This Thread

• At what point do you end a roll out.
  Joseph Pregler -- Monday, 21 May 2018, at 6:06 p.m.
  • At what point do you end a roll out.
    neilkaz -- Monday, 21 May 2018, at 6:15 p.m.
  • At what point do you end a roll out.
    roadkillbooks -- Monday, 21 May 2018, at 9:01 p.m.
  • At what point do you end a roll out.
    Phil Simborg -- Tuesday, 22 May 2018, at 12:09 a.m.
  • At what point do you end a roll out.
    Timothy Chow -- Thursday, 24 May 2018, at 12:21 a.m.