Blind Chess Olympiad the most significant sporting event in the international field of chess for the blind to date. Blind Chess Olympiad The Blind Chess Olympiad is an international chess competition for the blind in which teams from all over the world compete against each other. The event takes place every four years, and is sponsored by the International Braille Chess Association. The Blind Chess Olympiad is the largest sporting event in the international field of chess for the visually impaired. The forerunner to the Blind Chess Olympiads was a blind chess tournament held in Rheinbreitbach, Germany in 1958. The winner of the
Return period interest and formula_5 is the counting rate. If the return period of occurrence is 1 in 234 years (formula_5 = 0.0043) then the probability of no occurrence in ten years is In a given period of "n" years, the probability of a given number "r" of events of a return period formula_5 is given by the binomial distribution as follows. In the limit of :formula_11, such that formula_12 then Take where Given that the return period of an event is 100 years, So the probability that such an event occurs "exactly once" in 10 successive years is: Return period is