Full Report for China Tangle by Christian Freeling

Full Report for China Tangle by Christian Freeling

China Tangle is a game using 63 of the 64 hexagonal tiles of a two-groups transcendental solution of the China Labyrinth as a board.

Generated at 2023-06-16, 04:39 from 1000 logged games.

Rules

Representative game (in the sense of being of mean length). Wherever you see the 'representative game' referred to in later sections, this is it!

Definitions

The China Labyrinth has hexagons with every possible number and pattern of exits, in all possible rotations and reflections, without identical doubles.

A group consists of one or more like coloured checkers that are connected via unbroken paths of like coloured checkers. A group is maximal, meaning that part of a group is not a group.

Rules

The game starts on an empty board, White plays first, Black is entitled to a swap.

If a player on his turn puts one checker on a vacant cell, then all vacant cells that are open to further placements in the same turn are highlighted. These are cells with the same pattern of exits as the cell of the first checker that is placed, including all possible rotations and reflections.

The maximum number of checkers a player may place, if possible, equals 7 minus the number of exits of the cell on which the first checker is placed.

Obviously only one checker can be placed on the one cell with six exits. But place the first checker on a cell with one exit, then you can place six checkers, provided all six cells with one exit are vacant. It will not always be possible to place checkers up to the theoretical limit.

Goal

The game ends when the board is full, or earlier if a player resigns. On a full board the players' groups are compared, and the player with the largest group is the winner. If the players' largest groups are of equal size, then these two groups are out of competition and the next largest groups are compared (which may be the same size for one or both colours), and so on. Because the playing area has an odd number of cells the count is cascading down to an inevitable decision.

Miscellaneous

General comments:

Play: Combinatorial,Random Setup

Family: Combinatorial 2022

Mechanism(s): Connection,Territory,Tile

Components: Board

Level: Advanced

BGG Stats

BGG EntryChina Tangle
BGG Ratingnull
#Votersnull
SDnull
BGG Weightnull
#Votersnull
Yearnull

Kolomogorov Complexity Analysis

Size (bytes)34269
Reference Size10673
Ratio3.21

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 second20392.22 (49.04µs/playout)
Reference Size1911680.37 (0.52µs/playout)
Ratio (low is good)93.75

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.

State Space Complexity

% new positions/bucket

Samples811 
Confidence0.000: totally unreliable, 100: perfect

State space complexity (where present) is an estimate of the number of distinct game tree reachable through actual play. Over a series of random games, Ai Ai checks each position to see if it is new, or a repeat of a previous position and keeps a total for each game. As the number of games increase, the quantity of new positions seen per game decreases. These games are then partitioned into a number of buckets, and if certain conditions are met, Ai Ai treats the number in each bucket as the start of a strictly decreasing geometric sequence and sums it to estimate the total state space. The accuracy is calculated as 1-[end bucket count]/[starting bucklet count]

Playout/Search Speed

LabelIts/sSDNodes/sSDGame lengthSD
Random playout32217141763
search.UCT52,4098,878702

Random: 10 second warmup for the hotspot compiler. 100 trials of 1000ms each.

Other: 100 playouts, means calculated over the first 5 moves only to avoid distortion due to speedup at end of game.

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.

Win % By Player (Bias)

1: Player 1 (White) win %39.50±2.98Includes draws = 50%
2: Player 2 (Black) win %60.50±3.06Includes draws = 50%
Draw %0.00Percentage of games where all players draw.
Decisive %100.00Percentage of games with a single winner.
Samples1000Quantity 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.

UCT Skill Chains

MatchAIStrong WinsDrawsStrong Losses#GamesStrong Scorep1 Win%Draw%p2 Win%Game Length
0Random         
1UCT (its=2)63103309610.6260 <= 0.6566 <= 0.686053.900.0046.1075.32
5UCT (its=6)63103159460.6364 <= 0.6670 <= 0.696353.490.0046.5174.48
12UCT (its=13)63103559860.6095 <= 0.6400 <= 0.669352.940.0047.0673.56
14
UCT (its=15)
541
0
459
1000
0.5100 <= 0.5410 <= 0.5717
49.90
0.00
50.10
73.15
15
UCT (its=15)
531
0
469
1000
0.5000 <= 0.5310 <= 0.5618
56.50
0.00
43.50
73.07

Search for levels ended: time limit reached.

Level of Play: Strong beats Weak 60% of the time (lower bound with 95% confidence).

Draw%, p1 win% and game length may give some indication of trends as AI strength increases.

1st Player Win Ratios by Playing Strength

This chart shows the win(green)/draw(black)/loss(red) percentages, as UCT play strength increases. Note that for most games, the top playing strength show here will be distinctly below human standard.

Complexity

Game length70.06 
Branching factor13.88 
Complexity10^60.31Based on game length and branching factor
Computational Complexity10^7.09Sample quality (100 best): 7.69
Samples1000Quantity of logged games played

Computational complexity (where present) is an estimate of the game tree reachable through actual play. For each game in turn, Ai Ai marks the positions reached in a hashtable, then counts the number of new moves added to the table. Once all moves are applied, it treats this sequence as a geometric progression and calculates the sum as n-> infinity.

Move Classification

Board Size331Quantity of distinct board cells
Distinct actions449Quantity of distinct moves (e.g. "e4") regardless of position in game tree
Killer moves1A 'killer' move is selected by the AI more than 50% of the time
Killers: q24
Good moves83A good move is selected by the AI more than the average
Bad moves366A bad move is selected by the AI less than the average
Terrible moves1A terrible move is never selected by the AI
Terrible moves: v22
Response distance%19.92%Distance from move to response / maximum board distance; a low value suggests a game is tactical rather than strategic.
Samples1000Quantity of logged games played

Board Coverage

A mean of 18.83% of board locations were used per game.

Colour and size show the frequency of visits.

Game Length

Game length frequencies.

Mean70.06
Mode[69]
Median70.0

Change in Material Per Turn

Mean change in material/round2.25Complete round of play (all players)

This chart is based on a single representative* playout, and gives a feel for the change in material over the course of a game. (* Representative in the sense that it is close to the mean length.)

Actions/turn

Table: branching factor per turn, based on a single representative* game. (* Representative in the sense that it is close to the mean game length.)

Action Types per Turn

This chart is based on a single representative* game, and gives a feel for the types of moves available throughout that game. (* Representative in the sense that it is close to the mean game length.)

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

Trajectory

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 8% of the game turns. Ai Ai found 8 critical turns (turns with only one good option).

Position Heatmap

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

Good/Effective moves

MeasureAll playersPlayer 1Player 2
Mean % of effective moves59.3146.5170.72
Mean no. of effective moves5.264.096.30
Effective game space10^37.3810^12.7610^24.61
Mean % of good moves32.6162.695.79
Mean no. of good moves3.235.850.89
Good move game space10^20.8010^16.7210^4.08

These figures were calculated over a single game.

An effective move is one with score 0.1 of the best move (including the best move). -1 (loss) <= score <= 1 (win)

A good move has a score > 0. Note that when there are no good moves, an multiplier of 1 is used for the game space calculation.

Quality Measures

MeasureValueDescription
Hot turns51.43%A hot turn is one where making a move is better than doing nothing.
Momentum18.57%% of turns where a player improved their score.
Correction27.14%% of turns where the score headed back towards equality.
Depth4.40%Difference in evaluation between a short and long search.
Drama0.04%How much the winner was behind before their final victory.
Foulup Factor47.14%Moves that looked better than the best move after a short search.
Surprising turns2.86%Turns that looked bad after a short search, but good after a long one.
Last lead change31.43%Distance through game when the lead changed for the last time.
Decisiveness14.29%Distance from the result being known to the end of the game.

These figures were calculated over a single representative* game, and based on the measures of quality described in "Automatic Generation and Evaluation of Recombination Games" (Cameron Browne, 2007). (* Representative, in the sense that it is close to the mean game length.)

Unique Positions Reachable at Depth

0123456789
1633041878110837917241594822631691088789742380410

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 9.