hyper2 (version 2.0-1)

karpov_kasparov_anand: Karpov, Kasparov, Anand

Description

Data of three chess players: Karpov, Kasparov, and Anand. Includes two likelihood functions for the strengths of the players, and matrices of game results

Details

The strengths of chess players may be assessed using the generalized Bradley-Terry model. The karpov_kasparov_anand likelihood function allows one to estimate the players' strengths, propensity to draw, and also the additional strength conferred by playing white.

Likelihood functions karpov_kasparov_anand, kka_3draws and kka_3whites are created by files inst/karpov_kasparov_anand.R, inst/kka_3draws and inst/kka_3whites, which are heavily documented and include some analysis. Object karpov_kasparov_anand assumes that the draw potential is the same for all three players; likelihood function kka_3draws allows the propensity to draw to differ between the three players.

The reason that the players are different from those in the chess dataset is that the original data does not seem to be available any more.

Dataset kka refers to scorelines of matches between three chess players (Kasparov, Karpov, Anand). It is a list with names such as ‘karpov_plays_white_beats_kasparov’ which has value 18: we have a total of 18 games between Karpov and Kasparov in which Karpov played white and beat Kasparov.

The three matrices plays_white_wins, plays_white_draws, and plays_white_loses tabulate this information in a coherent way; and array kka_array presents the same information in a 3D array (but the names of the dimnames are lost).

All data drawn from chessgames.com, specifically

https://www.chessgames.com/perl/ezsearch.pl?search=karpov+vs+kasparov

Note that the database allows one to sort by white wins or black wins (there is a ‘refine search’ tab at the bottom). Some searches have more than one page of results.

Numbers here downloaded 17 February 2019. Note that only ‘classical games’ are considered here (rapid and exhibition games being ignored).

These objects can be generated by running script inst/kka.Rmd, which includes some further discussion and technical documentation and creates file kka.rda which resides in the data/ directory.

See Also

chess

Examples

# NOT RUN {
data(karpov_kasparov_anand)
maxp(karpov_kasparov_anand)
pie(maxp(karpov_kasparov_anand))
# }