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Effective errors and marginal doubles

Posted By: Florin Popa
Date: Friday, 23 September 2016, at 2:08 p.m.

In Response To: Size of the errors (Joe Russell)

"XG calculates the average error rate rather than the effective error rate. Would'nt calculating the effective error rate be more illuminating?"

Here are my thoughts, not sure if you mean the same. With the cube in action there are 4 states: ND, D/T,D/P, TGTD. After missing a marginal double and after two rolls next state can be, if lucky, D/P or TGTD where the effective error is huge but the probability P1 is low, D/T (probably a stronger one) again and no effective error with a higher probability P2 , or to be unlucky and go with P3 in status ND where the effective error is actually a gain. P3 I suppose it can't be so low because it was a marginal double. If you dont't double is likely you can do it later with better gain in equity and more probability to get a pass, risking of course a market loser and no possibility to cash instantly. So if we sum all the effective errors, considering only after a state transition occurs, I am not sure we can have something significant like "the net cost of the missed D/T errors cost was this" but it could. Missing a D/P it should be considered effective as well only in case of a state transition.

A ND/P and a TGTD/T generates a net gain, otherwise a loss. I really think backgammon is first of all a game between two human players who make mistakes, specially regarding cube decisions is similar to poker. The reality says is possible to have bigger gains (bluffs) from doubling against an opponent than a bot could have, someone is sure this is not a skill ? So I think having a parameter that measure this can be interesting. Anyway I would prefer such a system measurement because more corelated with the result.

Messages In This Thread

• Backgammon in the Wind - Erratum
  Chris Bray -- Monday, 19 September 2016, at 8:52 a.m.
  • Backgammon in the Wind - Erratum
    Casper Van der Tak -- Monday, 19 September 2016, at 11:12 a.m.
    • Backgammon in the Wind - Erratum
      Chris Bray -- Monday, 19 September 2016, at 5:37 p.m.
      • Equity of that situation
        Bob Koca -- Monday, 19 September 2016, at 6:17 p.m.
      • Backgammon in the Wind - Erratum
        Casper Van der Tak -- Monday, 19 September 2016, at 6:46 p.m.
      • Backgammon in the Wind - Erratum
        Florin Popa -- Monday, 19 September 2016, at 10:56 p.m.
        • Backgammon in the Wind - Erratum
          Casper Van der Tak -- Tuesday, 20 September 2016, at 7:42 a.m.
          • Size of the errors
            Florin Popa -- Tuesday, 20 September 2016, at 9:56 a.m.
            • Size of the errors
              Casper Van der Tak -- Tuesday, 20 September 2016, at 10:08 a.m.
            • Size of the errors
              Joe Russell -- Tuesday, 20 September 2016, at 10:42 a.m.
              • Size of the errors
                Florin Popa -- Tuesday, 20 September 2016, at 12:30 p.m.
              • Effective error rate
                Bob Koca -- Tuesday, 20 September 2016, at 1:18 p.m.
              • Effective errors and marginal doubles
                Florin Popa -- Friday, 23 September 2016, at 2:08 p.m.
                • Effective errors and marginal doubles
                  Bob Koca -- Friday, 23 September 2016, at 5:29 p.m.
                  • Effective errors and marginal doubles
                    Florin Popa -- Sunday, 25 September 2016, at 1:41 a.m.
  • Backgammon in the Wind - Erratum
    neilkaz -- Monday, 19 September 2016, at 6:49 p.m.
    • Rollout - 4 ply huge
      KenB -- Thursday, 22 September 2016, at 4:00 a.m.