Connected Speech Study for Cockpit Applications

Eleven subjects participated in a study designed to test the accuracy of a newer generation connected speech recognition system using 49 vocabulary words likely to be tested in an aircraft cockpit environment. The 49 vocabulary words were used to create 392 phrases. These phrases were divided into three groups: COMPLEX phrases, which contained more than five words, and two groups of SIMPLE phrases, which contained 5 words or less. The simple phrases were divided into SIMPLE ALTERNATE and SIMPLE NO-ALTERNATE phrases depending on whether or not the phrase was the only one in the entire vocabulary capable of carrying out a particular action once recognition occurred. Performance of the recognition system was measured with three accuracy statistics: WORD ACCURACY, which is most commonly reported in speech recognition research, PHRASE ACCURACY, which is gaining popularity in connected speech recognition research, and INTENT ACCURACY, which is probably the most relevent statistic that could be reported in research of this type. Significantly different word, phrase, and intent accuracy results were obtained for the three different phrase types. (MM)