Spanish Biology Olympiad of the Interior. The Board of Directors of the Spanish Biology Olympiad (OEB) is elected every four years. The Members are members of the Association OEB and are generally also responsible for organisation of the regional stages. The first Board of the OEB was established in 2009 to work together until 2013, with the following members: José Luis Barba, Maria Jose Lorente, Carmen Díaz, Javier Fernández-Portal, Anselmo Frade, Joaquín Rodríguez, Pedro Nozal and Judith Sanabria. Spanish Biology Olympiad The Spanish Biology Olympiad () is a national competition organised by the Spanish Association of Biology Olympiad since 2005. It is open
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