HMM Adaptation

Ï

¼

¼

¼

YJGTG VJG UWOOCVKQP KP VJG FGPQOKPCVQT KU VCMGP QXGT CNN RQUUKDNG YQTF UGSWGPEGU (QT .8%54 VJG ECNEWNCVKQP QH VJG FGPQOKPCVQT VGTOU KU EQORWVCVKQPCNN[ GZRGPUKXG UQ KV KU WUWCNN[ CRRTQZKOCVGF D[ EQPUKFGTKPI QPN[ VJG OQUV NKMGN[ YQTF J[RQVJGUGU IKXGP KP VJG HQTO QH C YQTF NCVVKEG EH 5GEVKQP CPF(KIWTG (QT OQTG FGVCKNU CDQWV FKUETKOKPCVKXG VTCKPKPI VJG TGCFGT KU TGHGTTGF VQ =?

5.5.4 HMM Adaptation

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

VJG DCEMITQWPF PQKUG EJCTCEVGTKUVKEU QT VJG URGCMGT KU CXCKNCDNG CFCRVCVKQP JCU VQ DG RGTHQTOGF WUKPI QPN[ VJG VGUV FCVC KP CP WPUWRGTXKUGF OCPPGT

(QWT EQOOQPN[ WUGF UEJGOGU VQ CFCRV VJG RCTCOGVGTU QH C URGGEJ *// ECP DG FKUVKPIWKUJGF $C[GUKCP CFCRVCVKQP =? CFCRVCVKQP DCUGF QP NKPGCT VTCPUHQTOC VKQPU =? FCVC ENWUVGTKPI DCUGF CFCRVCVKQP = ? CPF OQFGN EQORQUKVKQP VGEJ PKSWGU =?

$C[GUKCP GUVKOCVKQP CNUQ ECNNGF /#2 GUVKOCVKQP ECP DG UGGP CU C YC[ VQ KPEQTRQTCVG RTKQT MPQYNGFIG KPVQ VJG VTCKPKPI RTQEGFWTG D[ CFFKPI RTQDCDKNKUVKE EQPUVTCKPVU QP VJG OQFGN RCTCOGVGTU 6JG FKHHGTGPEG DGVYGGP /#2 VTCKPKPI CPF UVCPFCTF /. VTCKPKPI NKGU KP VJG CUUWORVKQP QH CP CRRTQRTKCVG RTKQT FKUVTKDWVKQP QH VJG RCTCOGVGTU VQ DG GUVKOCVGF +HKU VJG RCTCOGVGT XGEVQT QH VJG *// VQ DG VTCKPGF QP UQOG FCVC YKVJ C VTCPUETKRVKQP CPF KHKU VJG RTKQT 2&( QH VJGP VJG /#2 GUVKOCVGKU FGſPGF CU VJG OQFG QH VJG RQUVGTKQT 2&( QH KG

6JG *// RCTCOGVGTU CTG UVKNN GUVKOCVGF YKVJ VJG '/ CNIQTKVJO DWV WUKPI VJG /#2 TGGUVKOCVKQP HQTOWNCU =? 6JKU NGCFU VQ VJG /#2 CFCRVCVKQP VGEJPKSWG YJGTG EQP UVTCKPVU QP VJG *// RCTCOGVGTU CTG GUVKOCVGF DCUGF QP VJG RCTCOGVGTU QH CP GZKUVKPI OQFGN 5RGCMGTKPFGRGPFGPV CEQWUVKE OQFGNU ECP UGTXG CU UGGF OQFGNU HQT IGPFGT QT URGCMGT CFCRVCVKQP WUKPI VJG IGPFGTURGCMGT URGEKſE FCVC KG KP VJG CDQXG GSWCVKQP KU TGRNCEGF D[ YJGTGKU VJG RCTCOGVGT XGEVQT QH VJG UGGF OQFGNU /#2 CFCRVCVKQP ECP DG WUGF VQ CFCRV VJG OQFGNU VQ CP[ FGUKTGF EQPFKVKQP HQT YJKEJ UWHſEKGPV NCDGNGF VTCKPKPI FCVC CTG CXCKNCDNG /#2 GUVKOCVKQP JCU VJG UCOG CU[OR VQVKE RTQRGTVKGU CU /. GUVKOCVKQP DWV YJGP KPFGRGPFGPV RTKQTU CTG WUGF HQT FKHHGTGPV RJQPG OQFGNU VJG CFCRVCVKQP TCVG OC[ DG XGT[ UNQY RCTVKEWNCTN[ HQT NCTIG OQFGNU +V KU VJGTGHQTG CFXCPVCIGQWU VQ TGRTGUGPV EQTTGNCVKQPU DGVYGGP OQFGN RCTCOGVGTU KP VJG HQTO QH LQKPV RTKQT FKUVTKDWVKQPU = ?

.KPGCT VTCPUHQTOU CTG RQYGTHWN VQQNU HQT RGTHQTOKPI WPUWRGTXKUGF URGCMGT CPF GP XKTQPOGPVCN CFCRVCVKQP 6JG /. NKPGCT TGITGUUKQP /..4 VGEJPKSWG = ? KU RCTVKEWNCTN[ YGNNUWKVGF VQ WPUWRGTXKUGF CFCRVCVKQP 5KPEG VJG PWODGT QH VTCPUHQTOC VKQP RCTCOGVGTU KU UOCNN KV KU RQUUKDNG VQ CFCRV NCTIG OQFGNU YKVJ UOCNN COQWPVU QH FCVC +V EQPUKUVU QH ſPFKPI VJG VTCPUHQTOCVKQPWUWCNN[ CP CHſPG VTCPUHQTOCVKQP QH VJG *// )CWUUKCP OGCPU YJKEJ OCZKOK\GU VJG NKMGNKJQQF QH VJG CFCRVCVKQP FCVCHQT C IKXGP J[RQVJGUK\GF VTCPUETKRVKQP KG

Ê

6JG VTCPUHQTO RCTCOGVGTUACPFbCTG UJCTGF D[ VJG FKHHGTGPV RJQPG WPKVU CPF CTG VJGTGHQTG TQDWUV VQ TGEQIPKVKQP GTTQTU 6Q QDVCKP VJG /. CU[ORVQVKE RTQRGTVKGU KV KU PGEGUUCT[ VQ WUG OWNVKRNG NKPGCT VTCPUHQTOU CPF VQ CFLWUV VJG PWODGT QH NKPGCT VTCPU HQTOCVKQPU VQ VJG COQWPV QH CXCKNCDNG CFCRVCVKQP FCVC 6JKU ECP DG FQPG GHſEKGPVN[

D[ CTTCPIKPI VJG OKZVWTG EQORQPGPVU KPVQ C VTGG CPF F[PCOKECNN[ FGſPKPI VJG TGITGU UKQP ENCUUGU +P CFFKVKQP VQ VJG )CWUUKCP OGCPU /..4 CFCRVCVKQP KU QHVGP CRRNKGF VQ VJG XCTKCPEG RCTCOGVGTU 6JKU CFCRVCVKQP RTQEGFWTG ECP DG CRRNKGF VQ DQVJ VJG

VGUV FCVC CPF VTCKPKPI FCVC # PCVWTCN GZVGPUKQP QH VJKU CRRTQCEJ URGCMGT CFCRVKXG VTCKPKPI 5#6 KPEQTRQTCVGU UWRGTXKUGF /..4 KP VJG VTCKPKPI RTQEGFWTG CPF LQKPVN[

GUVKOCVGU VJG VTCKPKPI URGCMGT /..4 VTCPUHQTOU CPF VJG *// RCTCOGVGTU =? 6JG TGUWNVKPI 5#6 OQFGNU CTG DGVVGT UWKVGF VQ /..4 URGCMGT CFCRVCVKQP

)KXGP VJG UOCNN PWODGT QH RCTCOGVGTU HQT VJG /..4 VTCPUHQTOCVKQP QP VJG QTFGT QH RCTCOGVGTU HQT C UKPING TGITGUUKQP ENCUU YKVJ C DNQEM FKCIQPCN OCVTKZ VJKU CFCRVCVKQP VGEJPKSWG KU UVKNN UWKVCDNG YKVJ CU NKVVNG CU U QH CFCRVCVKQP FCVC KG QPN[

CDQWV HTCOGU +H NGUU FCVC KU CXCKNCDNG QVJGT CFCRVCVKQP VGEJPKSWGU WUKPI C UOCNNGT PWODGT QH CFCRVCVKQP RCTCOGVGTU CTG TGSWKTGF &CVC ENWUVGTKPI DCUGF CFCR VCVKQP OGVJQFU UWEJ CU VJG GKIGPXQKEGU UEJGOG =? CPF VJG ENWUVGT CFCRVKXG VTCKP KPI =? CTG UWEJ VGEJPKSWGU 6JG[ DQVJ WUG C YGKIJVGF UWO QH ECPQPKECN URGCMGT ENWUVGT OQFGNU VQ GUVKOCVG VJG )CWUUKCP OGCP XGEVQTU 6JGUG CFCRVCVKQP UEJGOGU ECP CNUQ DG EQODKPGF YKVJ UVCPFCTF /..4 CPF /#2 CFCRVCVKQP

/QFGN EQORQUKVKQP KU OQUVN[ WUGF VQ EQORGPUCVG HQT CFFKVKXG PQKUG D[ GZRNKEKVN[

OQFGNKPI VJG DCEMITQWPF PQKUG WUWCNN[ YKVJ C UKPING )CWUUKCP CPF EQODKPKPI VJKU OQFGN YKVJ VJG ENGCP URGGEJ OQFGN =? (QT RTCEVKECN TGCUQPU KV KU IGPGTCNN[ CU UWOGF VJCV VJG PQKUG FGPUKV[ KU )CWUUKCP CPF VJCV VJG PQKUG EQTTWRVGF URGGEJ OQFGN JCU VJG UCOG UVTWEVWTG CPF PWODGT QH RCTCOGVGTU CU VJG ENGCP URGGEJ OQFGN Ō V[R KECNN[ C EQPVKPWQWU FGPUKV[ *// YKVJ )CWUUKCP OKZVWTG 8CTKQWU VGEJPKSWGU JCXG DGGP RTQRQUGF VQ GUVKOCVG VJG PQKU[ URGGEJ OQFGNU KPENWFKPI VJG NQIPQTOCN CRRTQZ KOCVKQP CRRTQCEJ C PWOGTKECN KPVGITCVKQP CRRTQCEJ CPF C FCVC FTKXGP CRRTQCEJ =?

/QFGN EQORQUKVKQP JCU VJG CFXCPVCIG QH FKTGEVN[ OQFGNKPI VJG PQKU[ EJCPPGN CU QR RQUGF VQ CRRN[KPI DNKPF CFCRVCVKQP VGEJPKSWGU VQ VJG UCOG RTQDNGO

5.6 Decoding

6JG .8%54 FGEQFKPI RTQDNGO KU VJG FGUKIP QH CP GHſEKGPV UGCTEJ CNIQTKVJO VQ FGCN YKVJ VJG JWIG UGCTEJ URCEG QDVCKPGF D[ EQODKPKPI VJG CEQWUVKE CPF NCPIWCIG OQF GNU 5VTKEVN[ URGCMKPI VJG CKO QH VJG FGEQFGT KU VQ FGVGTOKPG VJG OQUV NKMGN[ YQTF UGSWGPEG IKXGP VJG NCPIWCIG OQFGN VJG RTQPWPEKCVKQP FKEVKQPCT[ CPF VJG CEQWU VKE OQFGNU KG

Ï

Ï

YJGTG VJG UWOOCVKQP KU VCMGP QXGT CNN RQUUKDNG RTQPWPEKCVKQPU CPF CNN RQUUKDNG *//

UVCVG UGSWGPEGU EQTTGURQPFKPI VQ VJG YQTF UGSWGPEG +P RTCEVKEG JQYGXGT KV KU EQOOQP VQ UGCTEJ HQT VJG OQUV NKMGN[ *// UVCVG UGSWGPEG 6JKU OCZKOWO CRRTQZ KOCVKQP CNUQ TGHGTTGF VQ CU 8KVGTDK UGCTEJ NGCFU VQ C UKORNKſGF XKGY QH VJG FGEQFKPI RTQDNGO

6JKU KU CP GCUKGT VCUM EQPUKUVKPI QH ſPFKPI VJG DGUV RCVJ VJTQWIJ C VTGNNKU VJG UGCTEJ URCEG YJGTG GCEJ PQFG TGRTGUGPVU CP *// UVCVG CV C IKXGP VKOG +V JCU DGGP UJQYP VJCV GXGP VJQWIJ VJG 8KVGTDK FGEQFKPI IKXGU QPN[ C ETWFG CRRTQZKOCVKQP QH VJG NKMG NKJQQF QH VJG YQTF UGSWGPEG VJG VYQ YQTF J[RQVJGUGU CTG CNOQUV CNYC[U XGT[ ENQUG 5QOG UKORNG GZVGPUKQPU QH VJG 8KVGTDK UGCTEJ CTG CDNG VQ EQORGPUCVG HQT OQUV QH FGEQFKPI CRRTQZKOCVKQPU KP RCTVKEWNCT VQ CXQKF RGPCNK\KPI YQTFU YKVJ OCP[ RTQPWP EKCVKQPU

+P OCP[ URGGEJ TGEQIPKVKQP U[UVGOU VJG ſTUV UVGR QH FGEQFKPI KU KFGPVKH[KPI VJG URGGEJ RQTVKQPU QH VJG CWFKQ UKIPCN 6JKU RTQEGUU KU FGUETKDGF KP VJG PGZV UWDUGE VKQP HQNNQYGF D[ OQTG FGVCKNU QP FGEQFKPI UVTCVGIKGU