A simple analytical model to quantify the probability P A S that team B wins a given set to team P A M in a volleyball match is developed. The probability of victory of team A in a whole match P A M is also calculated. Both probabilities are functions of a single parameter p, which represents the probability that team p beats team A in a rally. The model is interpreted in the one-dimensional random walk picture, establishing connections among the equations which describe both models. The impact of the 25 points finalization rule on the efficiency of the score system is studied. Finally, by using the model, the probability of victory of the men's Colombian volleyball team when it faces some of the best teams of South America is calculated.
volleyball; probability theory; Markov chains
