This invention is intended to enable initial ends to be opened irrespective of the configurations of Markov models and without entailing a large increase in amount of processing in Markov model aided voice recognition. For word models dependent on input length, matching paths are started in sequence within the initial end open ranges of sequences of input labels, and the initial likelihood values of the matching paths to be started are set at the greatest median likelihood value of other paths at the start. Matching is carried out in synchronization with input labels, and paths are disbranched in label units by applying beam search techniques to reduce amount of computation. For word models dependent on word model length, matching paths are started in sequence in each state within the initial end open range of each word model, and the initial likelihood values of the matching paths to be started are set at the greatest median likelihood value of other paths at the start. Matching is carried out in synchronization with states, and paths are disbranched in state units by applying beam searching techniques to reduce amount of computation. <IMAGE>
VOICE RECOGNITION