Abstract In the keyword spotting system based on dynamic match lattice spotting (DMLS), the minimum edit distance is used as the confidence measure. When the detection rate is increased, the false alarm rate is raised as well. Aiming at this problem, an approach integrating the posterior probability confidence measure with DMLS is proposed. Firstly, the posterior probability based on lattice is introduced with the index stage of DMLS. Secondly, data driven phone substitution, insertion and deletion costs are incorporated for more flexible phone sequence matching. Finally, the minimum edit distance and the posterior probability confidence measure are blended together to detect all occurrences of the keywords. The experimental results show that there is a certain complementarity between the minimum edit distance and posterior probability confidence measure and the equal error rate is relatively reduced.
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2015, Vol. 28 
