In this analysis we will explore who plays chess games, which types of games they play, and how those games end. First, we will begin by exploring the intersection of those 3 ideas. Then, we will explore each one independently more in depth.

Player Distributions with Game Types and Finishes

We are not seeking to create an engine which judges how well a came is played (Stockfish has that covered extremely well), rather, we are trying to understand which games are played and how they are played by the different ratings of players who play them.

Player Pairing Differences in Tournament and Non-Tournament Games All players have an Elo rating which attempts to quantify their chess skill. In any online game, typically it’s preferred if similarly skilled players are matched against each other. This heat map shows that games typically occur between players in similar Elo rating ranges. However, in tournaments, players can be matched against anyone else who has signed up for that tournament creating more unbalanced games. Note: The verticle and horizontal white lines indicate starting ranges for titled players (e.g. Grandmasters)

Game Endings in Different Game Types Lichess classifies games by their time control settings of how many minutes are initially on the clock for each player and how many seconds are added after each move. UltraBullet games are the quickest with 15 initial seconds for each player for all their moves over the entire game and no increment. Correspondence games are the longest with days allocated for each move. This stacked bar graph shows that games of different lengths of time controls typically end in different ways. In particular, many UltraBullet games simply end by one player’s time running out before a checkmate has been achieved (Time forfeit). However, the way games end for a particular time control variation does not change much for Tournament and Non-Tournament games.

Classical Draw Likelihood Classical is the longest game variation classification where the game is expected to be completed in one sitting. These games have an initial clock setting for each player at 7 or more minutes (although, hours for each player is also commonly seen). This setting allows players the most time to think about the board positions and anticipate how the game will play out. This heatmap shows that draws are most likely to occur when two higher rated players play against each other. This may be due to the fact that both players can more easily see that the game will get to the point where neither can win and agree to a draw or either player can force the game into a drawing position.

Blitz Resign vs. Checkmate Blitz is the next fastest time control variation with an initial clock setting for each player between 3 and 7 minutes. Removing games that end in a draw or end because one player runs out of time, this heatmap shows the difference in games ending by resignation (lighter squares) and checkmate (darker squares). It shows that when two higher rated players play, one of them is more likely to resign than when two lower rated players play. Like the last heatmap, this may be due to the fact that higher rated players can see when they are going to be checkmated and resign ahead of time.

Bullet Time Forfeit vs. Resign or Checkmate Bullet is the second fastest time control variation with an initial clock setting for each player greater than 15 seconds and less than 3 minutes. Removing games that end in a draw, this heatmap shows the difference in games ending by time forfeit (lighter squares) and resign or checkmate (darker squares). It shows that when two higher rated players play, they are more likely to complete the game (either by checkmating their opponent or resigning ahead of being checkmated) rather than simply running out of time. Even in these short games, high rated players are consistently able to play an entire game!