Full Report for Las Médulas(size=7,advanced) by Drew Edwards

Full Report for Las Médulas(size=7,advanced) by Drew Edwards

Las Médulas is an ancient Roman gold mine in Spain. Think of your stones as miners digging corridors through the rock. If they dig too closely together, the mine will collapse. To win, trap your opponent so that you have space to mine safely and they do not.

Generated at 2/17/21, 8:29 PM 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!

Play

On your turn, Mine and then Move one of your miners (i.e. stones).

Mining:

Movement:

Removal:

Winning

The first player who cannot Mine (place a tile) loses.

Miscellaneous

General comments:

Play: Combinatorial

Family: Combinatorial 2020

Mechanism(s): Connection,Movement,Capture,Stalemate

Components: Board

BGG Stats

BGG EntryLas Médulas(size=7,advanced)
BGG Rating8.5
#Voters2
SD0.5
BGG Weight3
#Voters1
Year2020

BGG Ratings and Comments

UserRatingComment
PSchulman8
rsb762gm9Fun, moderately strategic, fast moving game with simple rules.

Kolomogorov Complexity Analysis

Size (bytes)27431
Reference Size10293
Ratio2.67

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 second1144.93 (873.41µs/playout)
Reference Size255160.62 (3.92µs/playout)
Ratio (low is good)222.86

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.

Playout/Search Speed

LabelIts/sSDNodes/sSDGame lengthSD
Random playout1,15956158,1597,5701368
search.UCB1,1982013113
search.UCT1,200191348

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: White win %50.60±3.10Includes draws = 50%
2: Black win %49.40±3.09Includes 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         
1
UCT (its=2)
617
0
383
1000
0.5865 <= 0.6170 <= 0.6466
47.30
0.00
52.70
135.92
2UCT (its=3)63102628930.6759 <= 0.7066 <= 0.735551.510.0048.49135.75
3
UCT (its=4)
536
0
464
1000
0.5050 <= 0.5360 <= 0.5667
51.80
0.00
48.20
135.42
4
UCT (its=5)
539
0
461
1000
0.5080 <= 0.5390 <= 0.5697
51.10
0.00
48.90
136.37
5
UCT (its=6)
578
0
422
1000
0.5471 <= 0.5780 <= 0.6083
50.40
0.00
49.60
135.24
6
UCT (its=7)
584
0
416
1000
0.5532 <= 0.5840 <= 0.6142
49.40
0.00
50.60
135.84
7
UCT (its=8)
622
0
378
1000
0.5915 <= 0.6220 <= 0.6515
50.60
0.00
49.40
135.60
8
UCT (its=9)
621
0
379
1000
0.5905 <= 0.6210 <= 0.6506
51.30
0.00
48.70
135.61
9UCT (its=10)63103409710.6193 <= 0.6498 <= 0.679249.330.0050.67135.88
10
UCT (its=11)
356
0
387
743
0.4434 <= 0.4791 <= 0.5151
50.61
0.00
49.39
135.44
11
UCT (its=11)
511
0
489
1000
0.4800 <= 0.5110 <= 0.5419
49.70
0.00
50.30
135.39

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 length131.76 
Branching factor53.25 
Complexity10^186.64Based on game length and branching factor
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

Distinct actions16130Number of distinct moves (e.g. "e4") regardless of position in game tree
Good moves1817A good move is selected by the AI more than the average
Bad moves14313A bad move is selected by the AI less than the average
Terrible moves3598A terrible move is never selected by the AI
Too many terrible moves to list.
Response distance5.61Mean distance between move and response; a low value relative to the board size may mean a game is tactical rather than strategic.
Samples1000Quantity of logged games played

Board Coverage

A mean of 56.20% of board locations were used per game.

Colour and size show the frequency of visits.

Game Length

Game length frequencies.

Mean131.76
Mode[135]
Median133.0

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 41% of the game turns. Ai Ai found 4 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 moves44.7944.7744.81
Mean no. of effective moves11.808.6214.94
Effective game space10^82.0210^37.5510^44.48
Mean % of good moves43.7543.4644.03
Mean no. of good moves18.5313.4323.55
Good move game space10^94.6310^47.7410^46.90

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 turns97.71%A hot turn is one where making a move is better than doing nothing.
Momentum28.24%% of turns where a player improved their score.
Correction45.80%% of turns where the score headed back towards equality.
Depth15.58%Difference in evaluation between a short and long search.
Drama1.27%How much the winner was behind before their final victory.
Foulup Factor46.56%Moves that looked better than the best move after a short search.
Surprising turns0.76%Turns that looked bad after a short search, but good after a long one.
Last lead change90.08%Distance through game when the lead changed for the last time.
Decisiveness2.29%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.)

Opening Heatmap

Colour shows the success ratio of this play over the first 10moves; black < red < yellow < white.

Size shows the frequency this move is played.

Unique Positions Reachable at Depth

0123
112715445891361

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.

Puzzles

PuzzleSolution

Black to win in 3 moves

White to win in 3 moves

White to win in 3 moves

Weak puzzle selection criteria are in place; the first move may not be unique.