In a round-robin tournament (where a player versus every other in the tournament in turn), do players who drop out of the tournament after a few rounds affect the probability of winning for those who played against them throughout the course of the tournament so far (in the cases that some competitors lost to this player while others won)?
If they do affect such probabilities of winning, do we retroactively change the points awarded for wins/draws/losses/forfeits against this player? What is the fairest way to handle such a situation, or do we perhaps design the points system in preparation such that this is not a problem?