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dqg jlyh lw wr kljkhu w|shv1 Wkxv/ wkh uljlg0sulfh vfkhph pd{lpl}hv erwk ri wkh wzr whupv1 Krzhyhu/

hyhq li I@i lv qrw lqfuhdvlqj hyhu|zkhuh/ li u � �� lv odujh hqrxjk/ wkh sur�w0dw0wkh0wrs whup grplqdwhv/

dqg wkh srlqwzlvh remhfwlyh lv pd{lpl}hg e| jlylqj dv pxfk pdunhw0vkduh dv srvvleoh wr kljk w|shv1

Ilqdoo|/ rxu dvvxpswlrq wkdw i+�, A 3 +ru/ pruh jhqhudoo|/ li i 3+�, A 3, lpsolhv wkdw I@i lv lqfuhdvlqj

dw �= Wkxv/ wkhuh h{lvwv d sulflqj ixqfwlrq wkdw lv uljlg dw wkh erwwrp dqg |lhogv shu0shulrg sur�wv vwulfwo|

juhdwhu wkdq wkh vwdwlf Qdvk htxloleulxp +zklfk uhtxluhv s vwulfwo| lqfuhdvlqj,1 Wkhq/ zkhq �upv duh

vx�flhqwo| sdwlhqw/ wklv sulflqj vfkhph fdq eh vxvwdlqhg lq d vwdwlrqdu| htxloleulxp/ xvlqj wkh wkuhdw ri

uhyhuvlrq wr wkh vwdwlf Qdvk htxloleulxp wr vdwlvi| wkh r�0vfkhgxoh frqvwudlqwv1

Ohppd 91 Vxssrvh ghpdqg lv grzqzdug0vorslqj dqg frqvlghu dq| glvwulexwlrq ixqfwlrq I1 Ohw +s> W ,

vdwlvi| wkh frqvwudlqwv ri wkh Phfkdqlvp Ghvljq Surjudp dqg ohw +�s> �W � 3, eh wkh fruuhvsrqglqj qr0zduv

phfkdqlvp iurp Ohppd 71 Ohw \ +�, @ �+�> �> �s, � ^�+�> �> s, � W +�,` eh wkh srlqwzlvh qhw dgydqwdjh

ri wkh frqvwuxfwhg qr0zduv vfkhgxoh �s1 Wkhq \ lv gl�huhqwldeoh doprvw hyhu|zkhuh/ dqg zkhuh lw h{lvwv/

vljq^\3

+�,`@vljq^�s+�,� s+�,`= wkh qhw dgydqwdjh lqfuhdvhv zkhuh dqg rqo| zkhuh �s h{fhhgv s1

Surri1 E| Plojurp*v +4<<<, hqyhorsh wkhruhp/ \ lv gl�huhqwldeoh doprvw hyhu|zkhuh1 Xvlqj Ohppd 6

dqg wkh idfw wkdw s dqg �s duh pdunhw vkduh htxlydohqw +l1h1/ P+�> �s, @P+�> s, ,/ zkhuh lw h{lvwv/

\ 3+�, @ ��+�> �> �s,���+�> �> s, @P+�> s, +G+s+�,,�G+�s+�,, =

Wkh uhvxow iroorzv vlqfh ghpdqg lv grzqzdug0vorslqj1

73

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Ohppd :1 Vxssrvh ghpdqg lv grzqzdug0vorslqj dqg frqvlghu dq| glvwulexwlrq ixqfwlrq I1 Iru dq| �3

zkhuh s lv vwulfwo| lqfuhdvlqj ru mxpsv xs/ li +s> W , vdwlv�hv wkh rq0vfkhgxoh lqfhqwlyh frqvwudlqw zlwk qrzduv lq wkh qhljkerukrrg ri �

3

> wkhq s+�3

, ? sp+�3,=

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e| wkh vwulfw txdvl0frqfdylw| ri �1 Exw vxfk d sulflqj ixqfwlrq fdqqrw eh lqfhqwlyh frpsdwleoh zlwkrxw

d zdu dw �3/ vlqfh wkh orzhu sulfh r�huv kljkhu pdunhw vkduh dqg kljkhu sur�w0li0zlq1

Ohppd ;1 Vxssrvh ghpdqg lv grzqzdug0vorslqj dqg frqvlghu dq| glvwulexwlrq ixqfwlrq I1 Ohw +s> W ,eh lqfhqwlyh0frpsdwleoh/ dqg vxssrvh wkdw wkh frqvwuxfwhg qr0zduv phfkdqlvp +�s> �W � 3, wkdw |lhogv wkhvdph pdunhw vkduh +iurp Ohppd 7, lv vxe0prqrsro| iru wkh orzhvw w|sh= �s+�, � sp+�,1 +l, Wkhq wkhqr0zduv phfkdqlvp lv srlqwzlvh dv jrrg dv lwv zlwk0zduv frxqwhusduw= �+�> �> �s, � ^�+�> �> s,�W +�,`> irudoo �= +ll, Ixuwkhu/ wkh qr0zduv phfkdqlvp lv vwulfwo| ehwwhu li W A 3 rq d vhw ri srvlwlyh phdvxuh1

Surri1 +l, Lw vx�fhv wr vkrz plq� \ +�, � 3= Li � plqlpl}hv \ / wkhq zh duh grqh vlqfh �s zdv frqvwuxfwhg

vr wkdw \ +��, @ 3= D qhfhvvdu| frqglwlrq iru d plqlpxp dw �� lq wkh lqwhulru +�> �, lv \ 3 +��, @ 3 1 Exw

wkhq Ohppd 9 jlyhv s+��, @ �s+��, dqg vr �+��> ��> �s, @ �+��> ��> s,= Jlyhq W +��, � 3> zh frqfoxgh

\ +��, � 3= Odvwo|/ li � plqlpl}hv \ / wkhq \ 3+�, � 3> lpso|lqj s+�, � �s+�,= Vlqfh �s+�, � sp+�,> zh

frqfoxgh �+�> �> �s, � �+�> �> s,> dqg vr \ +�, � 3=

+ll, Qrz vxssrvh wkdw W +�, A 3 rq d vhw ri srvlwlyh phdvxuh= Li +s> W , lv rswlpdo/ vlqfh wkh qr0zdu

vfkhph lv zhdno| ehwwhu srlqwzlvh/ lw iroorzv wkdw +d, �+�> �> s, � W +�, @ �+�> �> �s, doprvw hyhu|zkhuh1

Exw wklv lpsolhv �s+�, 9@ s+�, doprvw hyhu|zkhuh wkdw W +�, A 31 Iurp wklv dqg Ohppd 9 lw iroorzv

wkdw +e, \ 3+�, 9@ 3 rq d vhw ri srvlwlyh phdvxuh= Vlqfh e| Ohppd 6/ \ +�, @ \ +��, .U ��

�\ 3+��,g��/ +e, lv

lqfrqvlvwhqw zlwk \ +�, @ 3 doprvw hyhu|zkhuh1

Surri ri Sursrvlwlrq := E| Sursrvlwlrq 4 +6,/ sh+�, � sp+�,= Wkhq Ohppd ; dssolhv wr dq| ixoo|0

vruwlqj +s> W , dqg +sh> W h � 3, dqg vr wkh odwwhu lv wkh xqltxh vroxwlrq wr wkh Phfkdqlvp Ghvljq Surjudp

dprqj ixoo| vruwlqj sulfh vfkhgxohv1 Wkh dujxphqw wkdw sh pxvw wkhq eh wkh rswlpdo ixoo|0vruwlqj VSSH

iroorzv dv lq Sursrvlwlrq 51

Surri ri Sursrvlwlrq ;= Frqvlghu �uvw d vwhs dw wkh erwwrp rq ^�> {`1 Vxssrvh s+{, A sp+{,= Exw

wkhq/ zh fdq �qg d ehorz0prqrsro| sulfh zklfk jlyhv wkh vdph sur�wv wr {/ wkxv suhvhuylqj +LF0rqP,/

exw vwulfwo| lpsurylqj wkh sur�w iru doo w|shv ehorz {1 Wkhq/ frqvlghu vhwwlqj W +�,@3= Vlqfh { lv dw ru

ehorz0prqrsro|/ orzhulqj wkh sulfh dqg holplqdwlqj wkh zdu doorzv xv wr pdlqwdlq +LF0rqP,1 Djdlq/ doo

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suhylrxv dujxphqwv zrxog lpso| wkdw sur�wv duh lpsuryhg e| orzhulqj wkh sulfh dqg holplqdwlqj wkh

zdu= Li s lv vwulfwo| lqfuhdvlqj dw wkh erwwrp/ vlqfh e| Ohppd : wkh qr0zdu sulfhv duh ehorz0prqrsro|/

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frqvlghu d vwhs dw wkh wrs1 Vxssrvh s+|, ? sp+|,= Exw wkhq/ zh fdq �qg dq deryh0prqrsro| sulfh zklfk

jlyhv wkh vdph sur�wv wr |/ wkxv suhvhuylqj +LF0rqP,/ exw vwulfwo| lpsurylqj wkh sur�w iru doo w|shv

deryh |1 Wkhq/ frqvlghu vhwwlqj W +��, @ 3= Vlqfh | lv dw ru deryh0prqrsro|/ holplqdwlqj wkh zdu uhtxluhv

udlvlqj wkh sulfh wr pdlqwdlq +LF0rqP,1 Djdlq/ doo w|shv deryh | suhihu wkh h{fkdqjh1

Surri ri Sursrvlwlrq <= Vxssrvh wkdw +s> W ,> zkhuh W A 3 rq d vhw ri srvlwlyh phdvxuh/ lv d

vroxwlrq1 Ohw +�s> �W � 3, eh wkh qr0zdu/ pdunhw0vkduh htxlydohqw vfkhph1 Ohw { � � eh wkh �uvw srlqw ri

vwulfw lqfuhdvh ri �s= Frqvlghu vhyhudo fdvhv1 Lq fdvh +l,/ { @ �1 Wklv lpsolhv �s+�, ? sp+�, e| Ohppd :1

Lq fdvh +ll,/ { A �/ dqg { lv wkh rqo| srlqw ri vwulfw lqfuhdvh ri �s1 Lq fdvh +lll,/ wkhuh duh pruh wkdq wzr

srlqwv ri vwulfw lqfuhdvh> e| wkh dvvxpswlrqv ri wkh sursrvlwlrq/ wklv lpsolhv �s+�, ? sp+�,=

74

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Qrz revhuyh wkdw lq fdvh +ll,/ Sursrvlwlrq ; hvwdeolvkhv wkdw +�s> �W � 3, kdv kljkhu sd|r�v/ zkloh lq

fdvhv +l, dqg +lll,/ Ohppd ; lpsolhv wkdw +�s> �W � 3, kdv kljkhu sd|r�v/ dv ghvluhg1

Ohppd <1 Vxssrvh wkdw ghpdqg lv lqhodvwlf dqg wkdw wkhuh h{lvwv dq { � �� vxfk wkdw I lv orj0frqfdyhrq ^�> {, dqg orj0frqyh{ rq ^{> ��`1 Gh�qh wkh plqlpxp h�flhqf| uhqw wkh �upv pd| uhfhlyh zkhq wkhrq0vfkhgxoh frqvwudlqwv duh vdwlv�hg e|= aU @ plqsH^

Ii+�,P+�> s,`1 Wkhq=

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+ll, Li �upv duh vx�flhqwo| sdwlhqw/ Yv @ aU@+4� �, 5 Yv=+lll, Li I lv orj0frqfdyh +{ @ ��,/ wkhq iru doo glvfrxqw idfwruv �> Yv @ �QH@+4� �, @ aU@+4� �,=

Surri1 Zh ehjlq zlwk sduw +ll,1 Vxssrvh wkdw +s> y, lpsohphqwv Yv1 Wkh r�0vfkhgxoh frqvwudlqw iru��

uhtxluhv wkdw �+�� � s+��,,P+��> s, . ��y+s+��,> s, � �Yv= Xvlqj +815,/ wkh rq0vfkhgxoh lqfhqwlyh frqvwudlqwv

lpso| wkdw

�+�� � s+��,,P+��> s, . ��y+s+��,> s, .H^I

i+�,P+�,` @ Yv= +4314,

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sO+��, @ 4q��. q�4

q{ dqg wkh sulflqj vfkhph lv uljlg rq ^{> ��` dqg vwulfwo| lqfuhdvlqj hovhzkhuh1 Xqghu rxu

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uhqwv1 Wkh frqwlqxdwlrq ydoxh ixqfwlrq yO vshfl�hv yO+s+�,, @ Yv li �m ? { iru dq| �up m +l1h1 li

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vfkhgxoh frqvwudlqw iru ��/ vr wkdw sur�w0dw0wkh0wrs lv �Yv= Wkh rq0vfkhgxoh frqvwudlqwv wkhq lpso| wkdw

wkh sd|r� iurp wklv frooxvlyh vfkhph lv �Yv.aU= Qrz/ zh nqrz iurp +4315, wkdw �Yv.

aU � Yv1 Ixuwkhu/

li wklv frooxvlyh vfkhph lv dq VSSH vfkhph/ wkhq wkh gh�qlwlrq ri Yv lpsolhv wkdw �Yv .aU � Yv= Khqfh/

li wklv frooxvlyh vfkhph vdwlv�hv doo rwkhu r�0vfkhgxoh lqfhqwlyh frqvwudlqwv/ dqg li �upv duh vx�flhqwo|

sdwlhqw wkdw yu 5 Yv> wkhq Yv @aU@+4� �, 5 Yv=

Wr vhh wkdw wkh sursrvhg vfkhph lqghhg vdwlv�hv doo rwkhu frqvwudlqwv/ qrwlfh wkdw vlqfh sO+��, A {>

rq0vfkhgxoh lqfhqwlyh frpsdwlelolw| ghwhuplqhv sO iru � ? {> dqg lq sduwlfxodu lw uhtxluhv wkdw sO+�, A �

iru doo �1 Vlqfh wkh sulflqj ixqfwlrq lv vwulfwo| lqfuhdvlqj rq wklv lqwhuydo/ wkhuh duh qr dgglwlrqdo r�0

vfkhgxoh frqvwudlqwv1 Ixuwkhu/ dv pd| eh frq�uphg/ dw wkh sulfh sO+��, @ 4q�� . q�4

q{/ wkh r�0vfkhgxoh

frqvwudlqw iru { +zkr lv whpswhg wr xqghu0fxw, lv vdwlv�hg h{dfwo| zkhq lw lv iru �� +zkr lv whpswhg wr

udlvh sulfh,183

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Li | lv vx�flhqwo| forvh wr ��> wkh lqfhqwlyh wr ghyldwh r�0vfkhgxoh fdq eh pdgh duelwudulo| vpdoo> dqg

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dqg u A ��=

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+l, dqg wkh dqdo|vlv surylghg lq wkh wh{w1

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eh wkh sxqlvkphqw xvhg iroorzlqj dq r�0vfkhgxoh ghyldwlrq lq wkh ruljlqdo vfkhph1 Zkhq wkh rq0vfkhgxoh

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Mxoolhq/ Euxqr/ _Sduwlflsdwlrq Frqvwudlqwv lq Dgyhuvh Vhohfwlrq Prghov/% Lqvwlwxw g*Hfrqrplh Lqgxv0

wulhooh/ Xqlyhuvlwh ghv Vflhqfhv Vrfldohv gh Wrxorxvh/ Grfxphqw gh Wudydlo 9:/ 4<<:1

Ndqgrul/ Plfklklur dqg Klwrvkl Pdwvkxvklpd/ _Sulydwh Revhuydwlrq/ Frppxqlfdwlrq dqg Frooxvlrq/%

Hfrqrphwulfd/ 4<<;/ 99= 95:09851

Nlkovwurp/ Ulfkdug dqg [dylhu Ylyhv/ _Frooxvlrq e| Dv|pphwulfdoo| Lqiruphg Ilupv/% Mrxuqdo ri Hfr0

qrplfv dqg Pdqdjhphqw Vwudwhj|/ 415/ Vxpphu 4<<5/ ss1 6:40<91

Ohzlv/ Wudf| dqg Gdylg Vdsslqjwrq/ _Frxqwhuyhlolqj Lqfhqwlyhv lq Djhqf| Sureohpv/% Mrxuqdo ri Hfr0

qrplf Wkhru|/ 4<;</ 7<= 5<706461

Pdjjl/ Jlrydqql dqg Dqguhv Urguljxh}/ _Rq Frxqwhuyhlolqj Lqfhqwlyhv/% Mrxuqdo ri Hfrqrplf Wkhru|/

4<<8/ 99= 56;05961

Pdv0Frohoo/ Dqguhv/ Plfkdho Zklqvwrq dqg Mhuu| Juhhq/ Plfurhfrqrplf Wkhru|1 R{irug Xqlyhuvlw|

Suhvv/ 4<<81

Pdvnlq/ Hulf dqg Mhdq Wluroh/ _D Wkhru| ri G|qdplf Roljrsro|/ LL= Sulfh Frpshwlwlrq/ Nlqnhg Ghpdqg

Fxuyhv/ dqg Hgjhzruwk F|fohv/% Hfrqrphwulfd/ 8916/ Pd| 4<;;/ ss1 8:40<<1

Pdvnlq/ Hulf dqg Mrkq J1 Uloh|/ _Rswlpdo Dxfwlrqv zlwk Ulvn Dyhuvh Ex|huv/% Hfrqrphwulfd/ 8519/

Qryhpehu 4<;7/ ss1 47:60484;1

PfDihh/ Suhvwrq dqg Mrkq PfPloodq/ _Elgglqj Ulqjv/% Dphulfdq Hfrqrplf Uhylhz/ ;516/ Mxqh 4<<5/

ss1 8:<08<<1

Phdqv/ Jduglqhu1 _Lqgxvwuldo Sulfhv dqg Wkhlu Uhodwlyh Lq�h{lelolw|/% Vhqdwh Grfxphqw 46/ :7wk Frqjuhvv/

4vw Vhvvlrq/ Mdq1 4:/ 4<681 Zdvklqjwrq G1F1

Sdxo Plojurp/ _Wkh Hqyhorsh Wkhruhpv% Plphr/ Vwdqirug/ 4<<<1

Ploov Iuhghulfn F1 Wkh Ehkdylru ri Sulfhv1 Qhz \run= Qdwlrqdo Exuhdx ri Hfrqrplf Uhvhdufk/ 4<5:1

P|huvrq/ Urjhu/ _Rswlpdo Dxfwlrq Ghvljq/% Pdwkhpdwlfv ri Rshudwlrqv Uhvhdufk/ 4<;4/ 9/ 8;0:61

Sruwhu/ Urehuw K1/ _Rswlpdo Fduwho Wuljjhu Sulfh Vwudwhjlhv/% Mrxuqdo ri Hfrqrplf Wkhru|/ 5<15/ Dsulo

4<;6/ ss1 64606;1

Udgqhu/ Ur|/ _Prqlwrulqj Frrshudwlyh Djuhhphqwv lq d Uhshdwhg Sulqflsdo0Djhqw Uhodwlrqvkls/% Hfrqr0

phwulfd/ 7</ 4<;4/ ss1 445:0447;1

Uh|qrogv/ Vwdqoh| V1/ Eduw M1 Zlovrq/ 4<<;/ _Sulfh Pryhphqwv ryhu wkh Exvlqhvv F|foh lq X1V1 Pdqx0

idfwxulqj Lqgxvwulhv/% Xqlyhuvlw| ri Dul}rqd/ plphr/ Pd|1

Urehuwv/ Nhylq/ _Fduwho Ehkdylru dqg Dgyhuvh Vhohfwlrq/% Mrxuqdo ri Lqgxvwuldo Hfrqrplfv/ 66/ 4<;8/

ss1 73407461

Urfkhw/ Mhdq0Fkduohv dqg Oduv Vwroh/ _Frpshwlwlrq lq Qrqolqhdu Sulfhv/% plphr/ Xqlyhuvlw| ri Fklfdjr1

Urwhpehuj/ Mxolr M1 dqg Jduwk Vdorqhu/ _D Vxshujdph0Wkhruhwlf Prgho ri Sulfh Zduv gxulqj Errpv/%

Dphulfdq Hfrqrplf Uhylhz> :916/ Mxqh 4<;9/ ss1 6<3073:1

Uxehqvwhlq/ Dulho dqg P1 \ddul/ _Uhshdwhg Lqvxudqfh Frqwudfwv dqg Prudo Kd}dug/% Mrxuqdo ri Hfr0

qrplf Wkhru|/ 63/ 4<;6/ ss1 7390461

Vfkhuhu/ I1P1/ Lqgxvwuldo Pdunhw Vwuxfwxuh dqg Hfrqrplf Shuirupdqfh/ 5qg hg1/ Fklfdjr= Udqg PfQdoo|/

4<;31

Vlprq/ Mrkq/ 4<<</ _Lq�dwlrq dqg Pdunxsv/% Plphr/ PLW1

Vsxoehu/ Gdqlho I1/ _Ehuwudqg Frpshwlwlrq Zkhq Ulydov* Frvwv Duh Xqnqrzq/% Mrxuqdo ri Lqgxvwuldo

Hfrqrplfv/ 7614/ Pdufk 4<<8/ ss1 40 441

7:

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Vwljohu/ Jhrujh/ _D Wkhru| ri Roljrsro|/% Mrxuqdo ri Srolwlfdo Hfrqrp|/ :514/ 4<97/ ss1 770941

Vzhh}|/ Sdxo P/ _Ghpdqg Xqghu Frqglwlrqv ri Roljrsro|/% Mrxuqdo ri Srolwlfdo Hfrqrp|/ 7:17/ Dxjxvw

4<6</ ss1 89;0:61

Wluroh/ Mhdq1 Wkh Wkhru| ri Lqgxvwuldo Rujdql}dwlrq/ Fdpeulgjh/ Pdvv1 dqg Orqgrq= PLW Suhvv/ 4<;;1

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