Full Report for Distrify by David Stoner

Full Report for Distrify by David Stoner

Unusually, a connection game on a square board


Play one piece with few constraints, or two pieces with rather more constraints. Connect opposite sides of the board to win (diagonals count). Crosscuts are always illegal. Three in a row is illegal when placing two pieces, as is placing both pieces diagonally adjacent.


General comments:

Play: Combinatorial

Family: Combinatorial 2015

Mechanism(s): Connection

Components: Board

BGG Stats

BGG EntryDistrify
BGG Rating6.8
BGG Weight0

BGG Ratings and Comments

luigi878Nice addition to the slowed-down-Crossway family.
mrraow6Interesting balancing act between playing one strong move or two weak ones.
milomilo122N/AVery eager to try this game. Connection games are my jam and this has among the coolest-seeming constraints I've seen.

Levels of Play

AIStrong WinsDrawsStrong Losses#GamesStrong Win%p1 Win%Game Length
Grand Unified UCT(U1-T,rSel=s, secs=0.01)360036100.0044.4473.69
Grand Unified UCT(U1-T,rSel=s, secs=0.03)36054187.8043.9064.78
Grand Unified UCT(U1-T,rSel=s, secs=0.07)360104678.2658.7056.33
Grand Unified UCT(U1-T,rSel=s, secs=0.20)36074383.7246.5148.60
Grand Unified UCT(U1-T,rSel=s, secs=0.55)36044090.0042.5042.20
Grand Unified UCT(U1-T,rSel=s, secs=1.48)36054187.8058.5435.98

Level of Play: Strong beats Weak 60% of the time (lower bound with 90% confidence).

Draw%, p1 win% and game length may give some indication of trends as AI strength increases; but be aware that the AI can introduce bias due to horizon effects, poor heuristics, etc.

Kolomogorov Complexity Estimate

Size (bytes)30026
Reference Size10577

Ai Ai calculates the size of the implementation, and compares it to the Ai Ai implementation of the simplest possible game (which just fills the board). Note that this estimate may include some graphics and heuristics code as well as the game logic. See the wikipedia entry for more details.

Playout Complexity Estimate

Playouts per second3833.03 (260.89µs/playout)
Reference Size522848.48 (1.91µs/playout)
Ratio (low is good)136.41

Tavener complexity: the heat generated by playing every possible instance of a game with a perfectly efficient programme. Since this is not possible to calculate, Ai Ai calculates the number of random playouts per second and compares it to the fastest non-trivial Ai Ai game (Connect 4). This ratio gives a practical indication of how complex the game is. Combine this with the computational state space, and you can get an idea of how strong the default (MCTS-based) AI will be.

Win % By Player (Bias)

1: White win %50.30±2.70Includes draws = 50%
2: Black win %49.70±2.70Includes draws = 50%
Draw %0.00Percentage of games where all players draw.
Decisive %100.00Percentage of games with a single winner.
Samples1312Quantity of logged games played

Note: that win/loss statistics may vary depending on thinking time (horizon effect, etc.), bad heuristics, bugs, and other factors, so should be taken with a pinch of salt. (Given perfect play, any game of pure skill will always end in the same result.)

Note: Ai Ai differentiates between states where all players draw or win or lose; this is mostly to support cooperative games.

Mirroring Strategies

Rotation (Half turn) lost each game as expected.
Reflection (X axis) lost each game as expected.
Reflection (Y axis) lost each game as expected.
Copy last move lost each game as expected.

Mirroring strategies attempt to copy the previous move. On first move, they will attempt to play in the centre. If neither of these are possible, they will pick a random move. Each entry represents a different form of copying; direct copy, reflection in either the X or Y axis, half-turn rotation.


Game length52.22 
Branching factor90.10 
Complexity10^101.05Based on game length and branching factor
Computational Complexity10^7.28Sample quality (100 best): 30.76
Samples1312Quantity of logged games played

Move Classification

Distinct actions122Number of distinct moves (e.g. "e4") regardless of position in game tree
Good moves71A good move is selected by the AI more than the average
Bad moves51A bad move is selected by the AI less than the average
Samples1312Quantity of logged games played

Change in Material Per Turn

This chart is based on a single playout, and gives a feel for the change in material over the course of a game.


This chart shows the best move value with respect to the active player; the orange line represents the value of doing nothing (null move).

The lead changed on 33% of the game turns. Ai Ai found 1 critical turn (turns with only one good option).

Overall, this playout was 95.83% hot.

Position Heatmap

This chart shows the relative temperature of all moves each turn. Colour range: black (worst), red, orange(even), yellow, white(best).


Table: branching factor per turn.

Action Types per Turn

This chart is based on a single playout, and gives a feel for the types of moves available over the course of a game.

Red: removal, Black: move, Blue: Add, Grey: pass, Purple: swap sides, Brown: other.

Unique Positions Reachable at Depth


Note: most games do not take board rotation and reflection into consideration.
Multi-part turns could be treated as the same or different depth depending on the implementation.
Counts to depth N include all moves reachable at lower depths.
Inaccuracies may also exist due to hash collisions, but Ai Ai uses 64-bit hashes so these will be a very small fraction of a percentage point.

Shortest Game(s)

No solutions found to depth 3.