“…The McNemar sentence-error-level significance test (not shown) indicates that the system with the lowest reported word and sentence error rate for the Class A utterances (sys24-a, the Unisys implementation of syntactic, semantic and pragmatic constraints in selecting the first candidate from an N-best listing provided by BBN, described in [11]) has an error rate that is significantly less than all but two other systems, (sysl8-a, the BBN "augmented training" system, and sys06-a, the SRI system). Performance differences (at the sentence error level) between these three systems, however, are not significant.…”