NextBackgammonMove

50%

White to play Pips 167 vs 167 Phase Contact

Position ID GnuBG format

Roll Joker heatmap

Search depth

Upper triangle and diagonal are the 21 distinct rolls. Turn on the heatmap to color each roll by how much it helps the side to play.

Best moves

#	Move	Equity	Diff	Win / Gammon

Tap a row to preview it on the board.

Rollouts play thousands of full games after each candidate move on every core, with dice-luck correction and identical dice for every candidate, so the comparison is fair.

Before the roll Centered cube, money play

Win

–

Gammon

–

Backgammon

–

Lose

–

Lose gammon

–

Cubeless eq.

–

No double

–

Double, take

–

Double, pass

–

Cubeful numbers use Janowski's interpolation with cube efficiency 0.68. All figures are from the side to play's point of view.

Strategy vs. luck

Two agents play cubeless money games. Every turn logs the skill loss (equity given up versus the engine's best play for that roll) and the luck (equity of the roll versus the average of all 21 rolls).

Agent A

Agent B

Games

Noise is the standard deviation of random error added to each candidate move's equity before choosing. The measured PR appears below.

A win rate

–

A points / game

–

Games

PR, agent A

–

PR, agent B

–

Luck share R²

–

Running win rate, agent A band = 95% interval

Luck vs. skill per game A minus B, equity

A wonB won

Horizontal axis: net dice luck. Vertical axis: net skill (equity A lost to errors subtracted from B's). Right of center means A had the better dice; above center means B made more costly errors. The R² tile is the share of per-game point swings explained by luck alone. Expect roughly 5 to 10 games per second, since every turn also scores all 21 alternative rolls.