Who was The Strongest Chess Player of All Time?

Computer Analysis of World Chess Champions,By Matej Guid and Ivan Bratko

We were interested in the chess players' quality of play regardless of the game score, which we evaluated with the help of computer analyses of individual moves made by each player. A method to assess the difficulty of positions was designed, in order to take into account the differences in players' styles and to compensate for the fact that calm positional players in their typical games have less chance to commit gross tactical errors than aggressive tactical players. We also give a carefully chosen methodology for using computer chess programs for evaluating the true strength of chess players.