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TRANSCRIPT
LinearIndexedGrammars
Formaldescriptionsofnon�local
dependencies
ChristianWartena
linguatecentwicklung&servicesGmbH
Hebelstraÿe14
69115Heidelberg
Germany
ChristianWartena,LinearIndexedGrammars
1
Survey
1.TheBasicIdea
2.VariationsontheInheritanceMechanism
�Basicvariants:IG,LIG,DIG.
�Restrictingtheruleformat:ILG,IRLG.
�RestrictionsonLIGs.
3.VariationsontheStorageStructure
�Control:makingdependenciesexplicit
�Usingabstractstorages
�Non�localdependenciesinTAG
�Compositestorages
ChristianWartena,LinearIndexedGrammars
2
1
TheIdea
NP
NP
thekennel
R
PP
P in
NP
which
S/PP
NP
Fido
VP/PP
Vtends
VP/PP
to
VP/PP
Vsleep
PP/PP
t
ChristianWartena,LinearIndexedGrammars
3
CP
NPi
wem
C'[i]
Vk
stehst
IP[ki]
NP
du
VP[ki]
t i
V'[k]
PP
innichts
V[k]
t k
V nach
ChristianWartena,LinearIndexedGrammars
4
2
VariationsontheInheritanceMechanism
IndexedGrammar(Aho1968)
Anindexedgrammarisa�vetupleG=(N;�;I;R;Ain)
N
nonterminalsymbols
�
terminalsymbols
I
indexsymbols
R
productionrulesoftheform:A�!
�
Ain
thestartsymbol
whereA2N,�2(NI
�
[�)�and�2I
�.
�) G�,if�=�A�#0�
A�!
X1� 1X2� 2:::Xk� k2R
�=�X1� 1#1X2� 2#2:::Xk� k#k�
where
�#i=#0ifXi2N,
�� i#i=�ifXi2�.
ChristianWartena,LinearIndexedGrammars
5
Example1
S
!
Tf
T
!
Tg
T
!
ABA
Af!
a
Bf!
b
Cf!
c
Ag!
aA
Bg!
bBCC
Cg!
bC Af
Af
Agf
a
aa
a
aa
Aggf
Aggf A
gf
b
b
b
b
b
Cf
Cf
Cf
Cf
Bf
b
b
b
Cgf
Cgf
Bgf
b
Bggf
Tggf
TgfT
fS
L=fanbn
2anjn�1g
ChristianWartena,LinearIndexedGrammars
6
LinearIndexedGrammar(Gazdar1988)
Anlinearindexedgrammarisa�vetupleG=(N;�;I;R;Ain)
N
nonterminalsymbols
�
terminalsymbols
I
indexsymbols
R
productionrulesoftheform:
A�!
�1B�!�2
A�!
w
Ain
thestartsymbol
whereA;B2N,�1;�22(NI
�
[�)�,w2�
�
and�;�2I
�
andwhere!isaspecialsymbolnotinN[�[I
�) G�,ifeither(1)or(2).
(1)
�= A�#Æ
A�!
�1B�!�22R
�= �1B�#�2Æ
(2)
�= A�Æ
A�!
w2R
�= wÆ
where
A;B2N,�1;�2; ;Æ2(NI
�
[�)�,�;�;#2I
�,w2�
�
ChristianWartena,LinearIndexedGrammars
7
CopyingofStacks(I)
VP[f]
IP[f]V
P[gf] t 2
t 3
NP
NP3
NP2
IP[gf]
V3
V2
V2[f]
V1V
1[gf]
VP[gf]
VP[f]
VP[]
NP1
IP
V3
V2
V1
NP
IP
VP[]
VP[f]
IP[f]
VP[f]
VP[gf] t
t
NP
NP
NP2
IP[gf]V
P[gf]
VerbraisinginIG
VerbraisinginLIG
ChristianWartena,LinearIndexedGrammars
8
CopyingofStacks(II)
Fidosleepsin
Marymade
Thekennel
and
S/NP
S/NP
S/NP
S/NP
which
R
NP
NP
Coordinationofconstituentswithgaps
ChristianWartena,LinearIndexedGrammars
9
DistributedIndexedGrammar(Staudacher1994)
Andistributedindexedgrammarisa�vetupleG=(N;�;I;R;Ain
N
nonterminalsymbols
�
terminalsymbols
I
indexsymbols
R
productionrulesoftheform:A�!
�
Ain
thestartsymbol
whereA2N,�2(NI
�
[�)�and�2I
�.
�) G�,if�=�A�#0�
A�!
X1� 1X2� 2:::Xk� k2R
�=�X1� 1#1X2� 2#2:::Xk� k#k�
where
�� i#i=�ifXi2�
�#1�#2�:::�#k=#0.
ChristianWartena,LinearIndexedGrammars
10
Example2
t
racontato
V
NP[j]
tPP[i]
V'[j]
VP[ji]
IP[ji]
NP
abiano
chestorie
CP[i]
midomando
acui
IP[i]
PP
CP
(1)a.Tuofratello,acuimidomandochestorieabbianoraccontato,
eramoltopreoccupato
b.Yourbrother,whomIwonderwhatstoriestheyhavetold,
wasveryworried
ChristianWartena,LinearIndexedGrammars
11
WeakGenerativeCapacity
context�sensitive
IG
DIGL
IGCFG
Figure1:Containmentrelationsofsomeclassesofindexed
grammars
LIGsareMildlyContextSensitive
1.LIGsonlygeneratelimitedcross-serialdependencies.
2.LIGshavetheconstantgrowthproperty.
3.LIGscanbeparsedinpolynomialtime.
ChristianWartena,LinearIndexedGrammars
12
CrossingDependencies
a
b
b
a
b
a
b
b
a
b
S[]
a
S[a]
b
S[ba]
b
S[bba]
a
S[abba]
b
T[babba]
b
T[abba]
a
T[bba] b
T[ba] b
T[a]
a
Figure2:CrossingdependenciesinastringandinaLIG�
derivationtree
ChristianWartena,LinearIndexedGrammars
13
VariationsontheRuleFormat
IndexedLinearGrammar
(DuskeandParchmann1984)
Anindexedlineargrammar
1
isanIG(DIG,LIG)
G=(N;�;I;R;Ain)whereeachproductionruleisoftheform:
A�!
�1B��2
whereA2N,B2N�,�1;�22�
�
and�;�2I
�.
Proposition1
fL(G)jGaCFGg�fL(G)jGaILGg�fL(G)jGaLIGg
Note.Foraproofnotethatfanbncndnjn2INgisanILLbut
fanxkykzkbncndnjn;k2INgisnot.
1IndexedLinearGrammars(indexedgrammarswithlinearrules)usuallyarecalledLinear
IndexedGrammars.HereIwillusethetermILGtodistinguishthemfromindexedgrammarswith
linearindexinheritance,thatarecalledLIGaswell.
ChristianWartena,LinearIndexedGrammars
14
IndexedRightLinearGrammar(Aho1968)
AnindexedrightlineargrammarisanILGG=(N;�;I;R;Ain)
whereeachproductionruleisoftheform:
A�!
�B�
whereA2N,B2N�,�2�
�
and�;�2I
�
Proposition2
fL(G)jGaIRLGg=fL(G)jGaCFGg
Note.
�ConstructaPDAwithNthestatesofthePDAandIthe
stackalphabetsuchthat:
Æ(A;a;f)=
f(B;g)jAf!
aBgg
�ForthereversedirectionconstructaCFGsuchthat
Af!
aBgif(B;g)2Æ(A;a;f)
ChristianWartena,LinearIndexedGrammars
15
RestrictionsonLIGs
(1)a.WhoididMarythink[thatJohnlovest i]?
b.WhoidoesMaryknow[afriendoft i]?
c.[Ofwhichmonth] idoesJohnhate[everydayt i]?
(2)a.*Whoidid[thatJohnlovest i]annoyMary?
b.*WhoididJohngive[afriendoft i]abook?
c.*[Ofwhichmonth] idoesJohnstrikehisdonkey[everyday
(3)a.WenidenktMaria,[daÿHansliebtt i]?
whothinksMaria
thatHansloves?
b.[VonPeter] ihatMarianoch[keinenFreundt i]kennengel e
ofPeter
hasMariayet
no�ACCfriend
knowlearn
(4)a.*WenibeunruhigtMaria,[daÿHansliebtt i]?
who�ACCannoysMariathatHansloves
b.*[VonPeter] ihatHansnoch[keinerFreundint i]eineRos
ofPeter
hasHansyet
no�DATfriend
arose
ChristianWartena,LinearIndexedGrammars
16
RightLinearIG(MichaelisandWartena1997)
ArightlinearindexedgrammarisanLIGG=(N;�;I;R;Ain)
whereeachproductionruleisoftheform:
A�!
�B�!
A�!
w
whereA;B2N,�2(NI
�
[�)�;w2�
�
and�;�2I
�.
Proposition3
fL(G)jGaRLIGg=
fL(G)jGaCFGg
Note.
�EveryCFGinGreibachnormal-formisanRLIG.
�AnRLIG-derivationcanbesimulatedbyanPDA,sincethere
isno�wrapping�:
GeneralLIG-case
�= A�#Æ
A�!
�B��2R
�= �B�#�Æ
RLIG-case
�= A�#Æ
A�!
�B�2R
�= �B�#Æ
ChristianWartena,LinearIndexedGrammars
17
RelevanceofRLIGs
�Achievingamaximumofstronggenerativecapacitywitha
minimumofweakgenerativecapacity
�Howmuchcanwedowith(weakly)contextfreeformalisms?
�SimilaritywithTreeInsertionGrammars(SchabesandWa-
ters1995)
�LIGsarenotevenneededforcrossserialdependenciesin
Dutch:ERLIGs
ExtendedRightLIG(MichaelisandWartena1999)
AnextendedrightlinearindexedgrammarisanLIG
G=(N;�;I;R;Ain)whereeachproductionruleisoftheform:
A�!
�B�!w
A�!
w
whereA;B2N,�2(NI
�
[�)�;w2�
�
and�;�2I
�.
ChristianWartena,LinearIndexedGrammars
18
Proposition4
fL(G)jGaCFGg�fL(G)jGaERLIGg�fL(G)jGaLIGg
Note.ERLIGsarenotclosedundersubstitution,whileLIGs
are.
a a a
d d d x i
x i�
1 x 0
b b b
c c c
� �
Figure3:ERLIG�Structureoffa
nb
ncnwd
n
jn2IN;w2L
0g.
ChristianWartena,LinearIndexedGrammars
19
Example3
'...thatGijshearsherteachingthechildrentosingpsalms'
CP
C dat
IP
NP
Gijs
VP0
VP
0 0[f]
VP
0 0[gf]
IP[gf]
NP
haar
VP1[gf]
IP[f]
NP
dekinderen
VP2[f]
NP
psalmen
V2
tV1 tV
0
hoort
V1
leren
V2
zingen
Figure4:DutchVR-StructureasanERLIG�tree
ChristianWartena,LinearIndexedGrammars
20
3
VariationsontheStorageStructure
�LIGsusepushdownsofindices
�LIGshavederivationtreeswithcontextfreespines
�Dopushdownsconstituteanappropriatewaytostorein-
dices?
CP
NPi
wem
C'[i]
Vk
stehst
IP[ki]
NP
du
VP[ki]
t i
V'[k]
PP
innichts
V[k]
t k
V nach
ChristianWartena,LinearIndexedGrammars
21
LinearDistinguishedGrammar(Weir1992)
AnLDGisatupleG=(N;�;R;Ain)
N
nonterminalsymbols
�
terminalsymbols
Ain
2Nthestartsymbol
R
productionrulesoftheform:A!
�1X!�2
LinearControlledGrammar(Weir1992)
AnLCGisapairK=G=H,
G=(N;�;R;Ain)aLDG,
HalanguageoverR(�thecontrollanguage�)
��) G�if�= (A;!)Æ
r=A!
�1X!�22R
�= �
0 1(X;!r)�
0 2Æ
�L(G=H)=fa1a2:::anj(S;�))
�
G
(a1;!1)(a2;!2):::(an;
ai2�;!i2Hfor1�i�ng.
ChristianWartena,LinearIndexedGrammars
22
Storage
AStorageisatupleS=(C;c�;P;F;m)
C
Con�gurations
c �2CInitialoremptycon�guration
P
Predicatesymbols
F
Instructionsymbols
m
Meaningfunctionassociatingevery
p2Pwithamappingm(p):C!
ftrue;falseg
f2Fwithapartialfunctionm(f):C!
Cassoziert.
Example4
Spd=(C;f�g;P;F;m)with
C��
�
forsome�nitealphabet�
P=ftop( )j 2�g
F=fpush( )j 2�g[fpopg[fidg
m(top( ))(a�)=(a= )
m(id)(a�)=a�
m(pop)(a�)=�
m(push( ))(a�)= a�
ChristianWartena,LinearIndexedGrammars
23
ContextFreeLinearSGrammar(Weir1994)
ACFL�S�Gisde�nedasatupleG=(N;�;S;R;Ain).
N
non�terminalsymbols
�
terminalsymbols
S
=(C;c0;P;F;m)astorage
Ain
2Nstartsymbol
R
productionrulesofthefollowingforms:
A!
if�then� 1Bf� 2
A!
if�thenw
where
A;B2N,�2BE(P),� 1;�22(N[�)�,f2F,w2�
�.
��) G�,ifeither(1)or(2).
(1)�=�(A;c)�
A!
if�then� 1Bf� 22
�=��
0 1(B;m(f)(c))�
0 2�
m(�)(c)=true
(2)�=�(A;c)�
A!
if�thenw2R
�=�w�
m(�)(c)=true
�L(G)=fwj(Ain;c�)) Gwg
ChristianWartena,LinearIndexedGrammars
24
S�Automaton
AnS�automatonisde�nedasatupleM
=(Q;�;S;Æ;q0;QF)
Q
states
�
inputalphabet
S
=(C;c�;P;F;m)astorage
q 0
2Qinitialstate
QF
�Q�nalstates
Æ
�Q����BE(P)�Q�F,transitionrelation
�(q1;xw;c1)`M
(q2;w;c2)if(q1;x;�;q2;f)2Æ
m(�)(c 1)=true
m(f)(c 1)=c 2
�LQ(M)=fwj(q0;w;c�)`
� M
(q;�;cf);q2Qfg
�LC(M)=fwj(q0;w;c�)`
� M
(q;�;c�)g
�LX(S)=fLjL=LX(M);M
isaS�automatong
ChristianWartena,LinearIndexedGrammars
25
Proposition5 fL
(G=H)jLaLDG;H2L(S)g
=
fL(G)jGaCFL�S�Gg
ChristianWartena,LinearIndexedGrammars
26
Ar 1
B r 2
Dr 3
d
Er 4
e
(d;r3)(e;r 1r 2r 4)
(q0;r1r 2r 4;c0)`
(q1;r2r 4;c1)`
(q2;r4;c2)`
(q4;�;c4)
(q0;r3;c0)`
(q3;�;c3)
(hA;q0i;c 0)
(hB;q1i;c 1)
(hD;q0i;c 0)
(hd;q3i;c 3)
d
(hE;q2i;c 2)
(he;q 4i;c 4)
e
ChristianWartena,LinearIndexedGrammars
27
(A;c0)
(B;c1)
(D;c0)
(d;c3)
d
(E;c2)
(e;c4)
e
Ar 1
B
r 2
Dr 3
d
Er 4
e
(d;r3)(e;r 1r 2r 4)
(qA;r1r 2r 4;c0)`
(qB;r2r 4;c1)`
(qE;r4;c2)`
(qf;�;c4)
(qD;r3;c0)`
(qf;�;c3)
ChristianWartena,LinearIndexedGrammars
28
TAG:AnotherwayofgeneratingCF�Spines
Proposition6
fL(G=H)jLaLDG;HaCFLg=
fSurf(G)jGaTAGg
d c
ba
�SNA
SSNA
DerivedTree
d c
ba
r 3r 2SNA
SSNA
AuxiliaryTree
�r 1S
InitialTree
LDG
r 1=
S
!
�
r 2=
S
!
aSd
r 3=
S
!
bSc
CFControlGrammar
Ain
!
Sr 1
S
!
�
S
!
r 2Sr 3
ChristianWartena,LinearIndexedGrammars
29
�Assumew.l.o.g.thattheunderlyingLDGhasonlyonenon�
terminalsymbol!
LDG
r 1=
S
!
aS
r 2=
S
!
bS
r 3=
S
!
Sa
r 4=
S
!
Sb
r 5=
S
!
�
CFControlGrammar
i:
S
!
Ar 5
ii:A
!
r 1Ar 3
iii:A
!
r 2Ar 4
iv:A
!
�
b
b
SNA
SSA(ii;iii)
SNA
iii:
SSA(ii;iii)
SNA
a
a
SNA
ii:
�SSA(ii;iii)
i:
ChristianWartena,LinearIndexedGrammars
30
storage
controllanguage
Gazdar'81
pushdown
CFL
Rambow'94multiset
??
Weir'88
pushdownofpushdowns
LIL
Wartena'99
concatenationofpushdownsERLIL
�Multiset
�Thewaylinguiststhinkaboutmovement
�Nocross�serialdependencies
�Verypowerfullwithoutfurtherrestrictions(e.g.bounded
size)
�PushdownofPushdowns
�Naturalhierarchy
�Nolinguisticinterpretation(??)
�ConcatenationofPushdowns
�Naturalhierarchy
�Linguisticmotivation
ChristianWartena,LinearIndexedGrammars
31
EmbeddingPushdowns
:::
abb
baaba
bab
aa
?r
6 w
6 w6 w6 w
6 w
6 w
Figure5:Con�gurationofathirdorderembeddedPDA
LinearPushdownofS
(Weir'94)
IfS=(C;c0;P;F;m)thenPlin(S)=(C
0;c
0 0;P
0;F
0;m
0)
C0
=
(���C)+forsome�nitealphabet�
c0 0
=
(�;c0)
P0
=
ftop( )j 2�g[ftest(p)jp2Pg
F0
=
fpush(�;f;i)j�2�+;f2F;1�i�j�jg[fpopg[
m0(push( 1::: i::: n;f;i))((�;c)�)=
( 1;c0):::( i�1;c0)( i;m(f)(c))( i+1;c0):::( n;c0)�
m0(pop)((�;c)�)=�
ChristianWartena,LinearIndexedGrammars
32
Proposition7
L(Plin(SPD))=fL(G)jGanLIGg
Note.InaderivationofanLIGeachgrammarsymbolisfol-
lowedbyastackofindices.
ChristianWartena,LinearIndexedGrammars
33
Concatenation
...RelativizedMinimalitymakestheblockinge�ectof
aninterveninggovernorrelativetothenatureofthe
governmentrelationinvolved.
Rizzi1990,p.2
Theapplicationof�ShortestMove�needstoberela-
tivizedtothetypeofconstituentsmovingandtothe
relevantlandingsite.
Marantz1995,p.355
Boundedconnectivityhypothesis:Thereisanaturalty-
pologyoflinguisticrelationssuchthatthepsychological
complexityofastructureincreasesquicklywhenmore
thanonerelationofanygiventypeconnectsa(partial)
constituent�(oranyelementof�)toanyconstituent
externalto�.
Stabler1994,p355
ChristianWartena,LinearIndexedGrammars
34
RestrictingTuplesofStacks(I)
�
b
a
a
b
a
b
a
b
a
a
a
?r
6 w
6 w
6 w
a.Concatenationw.r.t.reading(Cf.Breveglierietal.1996)
�
b
a
a
b
a
b
a
b
a
a
a
6 w
6 w
?r
?r
?r
b.Concatenationw.r.t.writing
Figure6:TuplesofStacks
ChristianWartena,LinearIndexedGrammars
35
RestrictingTuplesofStacks(II)
�Concatenationw.r.t.writingismoreplausiblesinceitsup-
portsclusteringof�landingsites�(asinmultiplewh-movement
orhead-movement)
�ProofsareeasierforConcatenationw.r.t.reading
�Concatenationw.r.t.readingcorrespondstoExtendedLeft
LinearIndexed(orDistinguished)Grammars
ProductofStorages(Wartena2000)
IfS1andS2arestoragesthentheirproductisde�nedas:
S1ÆS2=(C1�C2;c1 ��c2 �;P;F;m)where
P
=
f�pjp2P1g[f�pjp2P2g
F
=
f�fjf2F1g[f�fjf2F2g
m(�p)((c1;c2))=
m1(p)(c1)
m(�f)((c
1;c
2))=
(m1(f)(c1);c2)
m(�p)((c1;c2))=
m2(p)(c2)
m(�f)((c
1;c
2))=
(c1;m
2(f)(c2))
ChristianWartena,LinearIndexedGrammars
36
ProductofStorages(Wartena2000)
Æ
r
asÆbutm(�pop)((c
1;c
2))onlyde�nedifc1=c �
Æ
w
asÆbutm(�push)((c1;c2))onlyde�nedifc1=c �
Proposition8
L(SPDÆ rSPD)=fL(G)jGanELLIGg
InversionofStorages
IfS=(C;c�;P;F;m)thenSinv=(C;c�;P;F;m
0)
withm
0(f)=m(f)�1
�L(Sinv)=L(S)R
�SPDÆ wSPD=(SPDÆ rSPD)inv
�fL(G)jGanERLIGg=f(L(G))R
jGanELLIGg
�L(SPDÆ wSPD)=fL(G)jGanERLIGg
ChristianWartena,LinearIndexedGrammars
37
Ar 1
a
Br 2
b
D1
d
r 3E
r 5e
D2
dr 4
Fr 6
f
a
(a;�)(b;�)(d;�)(e;r 1r 2r 3r 5)(d;�)(f;r4r 6)(a;�)
(q0;r1r 2r 3r 5;c0)`
(q1;r2r 3r 5;c1)`
(q2;r3r 5;c2)`
(q3;r5;c3)`
(q5;�;c�)
(q0;r4r 6;c0)`
(q4;r6;c4)`
(q6;�;c�)
a)DerivationinanELLDGcontrolledbyanS�automaton.
(hA;q0i;abdedfa;(c 0;�))`
(hB;q1i;bdedfa;(c 1;a))`
(hD1;q2i;dedfa;(c 2;D2a))`
(hE;q3i;edfa;(c 3;D2a))`
(h�;q 5i;dfa;(c �;D2a))`
(hD2;q0i;dfa;(c �;a))`
(hF;q4i;fa;(c 4;a))`
(h�;q 6i;a;(c �;a))`
(h�;q 0i;�;(c�;�))
b)SimulationbyanSÆ rSpdautomaton.
ChristianWartena,LinearIndexedGrammars
38
(q0;abcdefg;(c0;�))`
(q1;bcdefg;(c1;�))`
(q2;cdefg;(c1;A))`
(q3;defg;(c1;BA))`
(q4;efg;(c�;BA))`
(q5;fg;(c�;A))`
(q6;g;(c �;A))`
(q7;�;(c �;�))
a)ComputationofanSÆ rSpd�automaton
(q0;�;q7)
a
r 1
(q1;�;q7)
b
r 2
(q2;A;q7)
c
r 3
(q3;B;q5)
d
r 4
(q4;B;q5)
r 5e
(q5;A;q7)
f
r 6 (q6;A;q7)
r 7g
(q0;r1r 2r 3r 4r 5;c0)`
(q1;r2r 3r 4r 5;c1)`
(q2;r3r 4r 5;c1)`
(q3;r4r 5;c1)`
(q4;r5;c�)`
(q5;�;c�)
(q5;r6r 7;c0)`
(q6;r7;c0)`
(q7;�;c�)
b)SimulationbyanELLDGandancontrollingS�automaton
ChristianWartena,LinearIndexedGrammars
39
CP
NP0
wie
C'[][np]
C+Vaux
heeft
IP[vaux][np]
NP
Gijs
I'[vaux][np]
VP[][np]
VP[v2][np]
VP[v1,v2][np]
IP[v1,v2][np]
NP
debuurman
VP[v1,v2][np]
IP[v2][np]
NP0
t
VP[v2]
NP
Engels
V2
tV1 t
V0
horenV
1latenV
2
praten
I+Vaux
t
�WenhatGijsdenNachbarnEnglischsprechenlassengehört?�
ChristianWartena,LinearIndexedGrammars
40
FinalRemarks
�NobigsystemsorprojectsforLIG
�Usefullforthethestudyof�movement�,non�localdepen-
denciesandtheirformalimplications.
�Helpfullfortheunderstandingofothermildlycontextsen-
sitiveformalisms(varyingfromTAGtoSlotGrammar)
ChristianWartena,LinearIndexedGrammars
41
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