About a year ago, ah_clem asked me for an example of an XG opening
book play that was based on a single rollout trial and was way off.
https://groups.google.com/g/rec.games.backgammon/c/_Ic-yT-mJoA/m/BvL1lj4XBgAJ
I couldn't come up with an example off the top of my head, but
finally noticed one today when XG dinged my first move of the
game as a double whopper.
XGID=-b----E-C---eE---c-e----B-:0:0:1:41:1:6:1:7:10
X:Me O:eXtremeGammon
Score is X:1 O:6 7 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O | | O X |
| X O | | O X |
| X O | | O |
| X | | O |
| X | | O |
| |BAR| |
| O | | X |
| O | | X |
| O X | | X |
| O X | | X O |
| O X | | X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 167 O: 167 X-O: 1-6/7 Crawford
Cube: 1
X to play 41
1. Book¹ 13/9 6/5 eq:+0.208
Player: 48.87% (G:18.17% B:2.37%)
Opponent: 51.13% (G:10.30% B:0.00%)
Confidence: ±0.000 (+0.208..+0.208) - [100.0%]
2. Book² 13/8 eq:+0.155 (-0.053)
Player: 49.13% (G:13.59% B:0.92%)
Opponent: 50.87% (G:15.51% B:2.06%)
Confidence: ±0.003 (+0.153..+0.158) - [0.0%]
3. Book³ 24/20 6/5 eq:+0.132 (-0.077)
Player: 48.86% (G:12.20% B:0.44%)
Opponent: 51.14% (G:14.01% B:0.69%)
4. Book³ 24/23 24/20 eq:+0.130 (-0.078)
Player: 48.91% (G:12.02% B:0.48%)
Opponent: 51.09% (G:13.03% B:0.53%)
9. Book¹ 24/23 13/9 eq:-0.006 (-0.214)
Player: 41.96% (G:12.25% B:0.75%)
Opponent: 58.04% (G:54.30% B:0.08%)
Confidence: ±0.000 (-0.006..-0.006) - [0.0%]
¹Generated by David Rockwell on 5/31/2013 using eXtreme Gammon 2.10
1 Games rolled with Variance Reduction.
Dice Seed: 1282080
Moves and cube decisions: 3-ply
²Generated by Steven Carey on 8/10/2012 using eXtreme Gammon 2.00
7776 Games rolled with Variance Reduction.
Dice Seed: 5
Moves: 3-ply, cube decisions: XG Roller
³Generated by GameSite 2000, Ltd on 5/21/2011 using eXtreme Gammon 2.00
Analyzed in XG Roller++
eXtreme Gammon Version: 2.19.207.pre-release, MET: Kazaross XG2
---
Tim Chow
--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)