Abstract strategy games: Difference between revisions
Abstract strategy games: Added examples |
Abstract strategy games: Expanded ratings |
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== Ratings == | == Ratings == | ||
Under perfect information and the absence of luck, it makes perfect sense to quantify a player's strength or skill level with a rating system. We can assign a number to a given player, and based on two rated players, we can estimate the outcome either in a single game, or an entire match consisting of a series of games. | Under perfect information and the absence of luck, it makes perfect sense to quantify a player's strength or skill level with a rating system. We can assign a number to a given player, and based on two rated players, we can estimate the outcome either in a single game, or an entire match consisting of a series of games. | ||
Given 2 ratings <math>R_A</math> and <math>R_B</math>, where <math>R_A \leq R_B</math>, we can estimate the ''expected score'' of player B as <math>\frac{1}{1+10^{-(R_B-R_A)/400}}</math>. Note the use of "expected score". In games where draws do not exist, this is simply the same as winrate. However, in games like chess where it exists, expected score is equivalent to winrate + 1/2 * drawrate. Additional formulas are required to separate winrate from drawrate in that case. | |||
Revision as of 10:57, 26 September 2025
An abstract strategy game is a board, card or other game where gameplay is mostly without a theme and a player's decisions affect the outcome. Such games are combinatorial, i.e. perfect information, don't involve non-deterministic elements (shuffled cards or dice rolls). This page will mostly be about two-player zero-sum games.
Common examples of such games include:
- Chess
- Hive
- Xiangqi (Chinese chess)
- Games from GIPF Project, such as YINSH.
- Connect 4
Ratings
Under perfect information and the absence of luck, it makes perfect sense to quantify a player's strength or skill level with a rating system. We can assign a number to a given player, and based on two rated players, we can estimate the outcome either in a single game, or an entire match consisting of a series of games.
Given 2 ratings and , where , we can estimate the expected score of player B as . Note the use of "expected score". In games where draws do not exist, this is simply the same as winrate. However, in games like chess where it exists, expected score is equivalent to winrate + 1/2 * drawrate. Additional formulas are required to separate winrate from drawrate in that case.
