RELATIONSHIP AMONG RECOGNITION RATE, REJECTION RATE AND FALSE ALARM RATE IN A SPOKEN WORD RECOGNITION SYSTEM

Detection of an unknown word or non-vocabulary word uttered by the use r is necessary in realizing a practical spoken language user-interface . This paper describes the evaluation of an unknown word processing me thod for a subword unit based spoken word recognizer. We have assessed the relationship between the word recognition accuracy of a system an d the detection rate of unknown words both by simulation and by experi ment of the unknown word processing method. We found that the resultan t detection accuracies using the unknown word processing are significa ntly influenced by the original word recognition accuracy while the de gree of such effect depends on the vocabulary size.