BBN	CU-HTK	CU-Con
Front-end	36 pole LPC	33 features VTN LDA + normalization	12th order PLP + energy
Segmentation	CI system Gender-dependent models	Agglomerative clustering Kullback-Leibler distance Merge adjacent segments	CMU's segmentation
Acoustic Model	Gender-dependent Type-independent Xword triphones	Gender-dependent Type-dependent Xword quinphones 5-pass MLLR adaptn. Word-end information used	RNNs Gender-independent Type-independent WI triphones Syllable information used
Language Model	Trigram and 4-gram 1st pass - trigram Adapted remote corpora	Trigram and 4-gram interpolated Trigram for initial MLLR phase Adapted remote corpora	65K lexicon Trigram and 4-gram interpolated Adapted remote corpora
Decoder	Xword trigram 2-pass decoding Fast match with CI models	Multipass lattice MLLR + Xword trigram	NOWAY stack decoder WI 4-gram
Performance	20.4% WER	15.9% WER	27.2% WER