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Exploring Multidominance in Tree Adjoining Grammar

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Title: Exploring Multidominance in Tree Adjoining Grammar


1
Exploring Multidominance in Tree Adjoining Grammar
  • Joan Chen-Main
  • joan_at_cogsci.jhu.edu
  • Department of Cognitive Science
  • Johns Hopkins University

2
In Two Places at Once
  • Some constructions seem like they have an element
    in two places at once
  • Joe bakes ___ and Sam eats cookies.
  • What did Emmy eat ___?

3
Standard Treatment Trees
  • Movement or ellipsis
  • Unique node immediately dominating each node

4
Alternative Treatment Graphs
Gärtner, Wilder, Abels, Goodall, and others
  • One element in one place
  • Mulitidominance

5
How are such graphs generated?
  • What introduces multidominance into the system?

6
Sarkar and Joshi (1996)
  • Some nodes are marked for contraction

7
Sarkar and Joshi (1996)
  • Node contraction results in multidominance

8
Example Conjoined VPs
  • Elementary trees

9
Example Conjoined VPs
  • VP coordination tree adjoined into eats tree
  • drinks tree substituted into coordination tree

10
Example Conjoined VPs
  • NP nodes contract

11
Example Conjoined VPs
  • Joe eats cookies and drinks tea.

12
Pushing the Proposal
  • Instead of being restricted to coordination . . .
  • Suppose node contraction is a general mechanism
    in the TAG system.
  • Where else might we see multidominance?

13
Overview
  • What such a system can do
  • Coordination
  • Movement
  • Interleaving
  • Factoring out recursion
  • Appropriate Restrictions
  • Island Constraints
  • Part of Coordinate Structure Constraint
  • Current Concerns
  • Linearization, Gapping, other part of CSC

14
Multidomination in Movement
  • PROPOSAL
  • Node contraction can replace elementary tree
    internal movement.

15
Example Wh-Question
  • Did-eat tree substitutes into wh-question tree

16
Example Wh-Question
  • DPs substitutes in to yield
  • What did Emmy eat?

17
The Interleaving Problem
  • Does Sam seem to like pizza?

18
Allowing Interleaving
  • Elementary trees marked for node contraction

19
Allowing Interleaving
  • The does seem tree adjoins into the to like tree

20
Allowing Interleaving
  • The to like tree substitutes into the yes-no
    question tree

21
Final Structure
22
Small Trees and Recursion
  • Hegarty (1993) Smaller trees allow further
    Factoring out of recursive structure
  • V, I, and some Cs not distinguished by the
    combinatory operations

23
Small Trees and Node Contraction
  • Head Movement in Hegartys system requires
    hiccup, two V positions.
  • With node contraction, we can maintain parallel
    between Eng and French.
  • Schematic for V to I movement

24
Island Constraints
  • Certain syntactic configurations block movement.
    (Ross 1967)
  • embedded questions
  • wh-relative clauses
  • subject islands
  • complex NPs
  • Coordinate Structure Constraint
  • Part A No conjunct can be a gap
  • Part B No element of a conjunct can be a gap if
    its filler is outside the conjunct

25
A Graph To Ban
26
A Graph To Ban
27
Deriving Island Effects
  • Impose a restriction on node contraction
  • After substitution, every node marked for
    contraction must have been contracted.
  • No such restriction following adjoining
  • Imposes some locality on node contraction
  • Intuition pieces of structure combined via
    substitution are somehow more distinct than
    pieces of structure combined via adjunction.

28
Locality on Node Contraction
Schematic
Derivation Trees OK not OK
29
Example Embedded Question Islands
Which party did Alice ask who you had invited
to?
  • Elementary trees marked for contraction

30
Example Embedded Question Islands
Which party did Alice ask who you had invited
to?
  • Problematic to combine these trees

31
The Unavoidable Problem
  • In the best case scenario . . .
  • The to-tree adjoins into the had invited tree.
  • Following adjoining, nodes waiting to be
    contraction are allowed.

32
The Unavoidable Problem
  • Next, the had invited tree substitutes into the
    question tree.
  • Following substitution, no contraction nodes are
    allowed to be leftover.
  • no way for all the nodes marked for contraction
    to do so.

33
Failed Derivation
Which party did Alice ask who you had invited
to?
34
Additional Island Effects
  • This restriction blocks extraction from
  • embedded questions
  • wh-relative clauses
  • subject islands
  • complex NPs

35
Coordinated DPs and the CSC
Joe watched a movie about Stevie Wonder and a TV
show about bridges.
36
Coordinated DPs and the CSC
Who did Joe watch a movie about ___ and a TV
show about bridges?

37
Coordinated DPs and the CSC
What did Joe watch a movie about Stevie Wonder
and ___?

38
Conclusions
  • Allowing general node contraction in TAG
  • Provides a unified mechanism for coordination and
    movement (sans traces)
  • Allows derivation of constructions with
    interleaved elements
  • Allows further factoring out of recursion
  • Can be restricted to derive island effects

39
Current Concerns
  • Linearization How do we pronounce these graphs?
  • Gapping How do we generate two argument
    structures from one verb?
  • Coordinated TPs and the Coordinate Structure
    Constraint

40
Linearization elementary trees
  • Elementary trees are indeed trees (and not
    graphs!).
  • The primitive relations are immediate dominance
    and sister precedence.
  • Sister precedence is not sensitive to
    segment/category distinction.
  • E.g. the lower segment of XP1 sister precedes BP

41
Linearization derived trees
  • Each elementary tree contributes immediate
    dominance and sister precedence information about
    the derived tree.
  • In the finished graph,
  • Dominance relation the transitive closure of
    available dominance information
  • Precedence relation derived from a modified
    non-tangling condition which uses notion of full
    dominance.

42
Linearization derived trees
  • Full-dominance non-tangling condition
  • If a sister-precedes ß, then everything a fully
    dominates precedes everything ß fully dominates.
  • Full-dominance
  • a fully dominates ? iff every path from ? to the
    root of the sentence includes a.
  • (Wilder 2001)

43
Simple Case Shared Subject
  • Joe eats cookies and ___ drinks tea.
  • ___ eats cookies and Joe drinks tea.

SPs affecting the contracted node DPS SP V1 ?
Joe gtgt eats, cookies DPS SP V2 ? Joe
gtgt drinks, tea
44
Simple Case Shared Subject
  • Joe eats cookies and ___ drinks tea.
  • ___ eats cookies and Joe drinks tea.

Other SPs will order remaining items VP1 SP BP
? eats, cookies gtgt and, drinks, tea B SP VP2 ?
and gtgt drinks, tea (VP2 fully dominate
Joe.) V1 SP DP1 ? eats gtgt cookies V2 SP DP2 ?
drinks gtgt tea
45
Simple Case Right Node Raising
  • Joe bakes ____ and Sam decorates cookies.
  • Joe bakes cookies and Sam decorates ____.

SPs affecting the contracted node V1 SP DPO ?
bakes gtgt cookies V2 SP DPO ? decorates gtgt
cookies
Contrasts with Pronounce-in-Highest-Position
strategy
46
Simple Case Shared Subj Obj
  • Joe bakes ____ and ___ decorates cookies.
  • Joe bakes cookies and ___ decorates ___.
  • ___ bakes ___ and Joe decorates cookies.
  • ___ bakes cookies and Joe decorates ___.

47
Simple Case Shared Subj Obj
SPs affecting the contracted nodes DPS SP V1'
? Joe gtgt bakes DPS SP V2' ? Joe gtgt
decorates V1 SP DPO ? bakes gtgt cookies V2 SP
DPO ? decorates gtgt cookies
SPs ordering remaining items VP1 SP BP ?
bakes gtgt and B SP VP2 ? and gtgt decorates
Contrasts with Wilders full-dominance LCA
48
Kaynes (1994) LCA
  • If a syntactic structure cannot provide the
    information needed to linearize its terminals,
    the structure is ill-formed.
  • Two kinds of violation
  • Antisymmetry
  • Totality

49
Antisymmetry Violations
  • What did Emmy ___ eat ___?

Symmetrical Pair DPO SP QC' ? what gtgt eat,
did, Emmy V SP DPO ? eat gtgt what
50
Avoiding Symmetry
  • Dominance provides a partial order on SP pairs
  • Give priority to information from the SP pair
    ordered earliest.
  • If a contradiction arises later, ignore it.
  • i.e. If you cant preserve order, pronounce as
    high as you can.

51
Avoiding Symmetry
  • What did Emmy ___ eat ___?

Symmetrical Pair DPO SP QC' ? what gtgt eat,
did, Emmy V SP DPO ? eat gtgt what
52
Totality Violations
John and Mary ate cookies.
John, Mary, and and are all unordered wrt ate and
cookies.
53
Coordinated Subjects
  • John and Mary ate cookies.

Need such a structure for sentences like John
and Mary met in the park.
54
Contraction of V', V, DP
John and Mary ate cookies.
Could allow contraction of X' nodes.Would need a
way to delete one of the anchor verbs.
55
Contraction of DP, V', V
Joe eats cookies and ice cream.
Allowing contraction of X' wont help Neither
VP1 nor VP2 fully dominate anything. And remains
unordered.
56
Coordinated Objects
Joe eats cookies and ice cream.
57
When Linearization Chooses
  • Coordinated Subjects
  • Conjoined DPs, no node contraction
  • If Conjoined TPs, then requires X' contraction
  • Coordinated Objects
  • Conjoined DPs, no node contraction
  • Even with X' contraction, NOT Conjoined TPs

58
Gapping
  • Sam likes beans and Joe ___ rice.
  • Linearization
  • Sam ___ beans and Joe likes rice.
  • Gapping RNR
  • Sam likes ___ and Joe ___ rice.
  • Gapping ATB movement
  • What does Sam like ___ and Joe ___ ___?

59
A pro-Verb Story for Gapping
  • pro-V is the lexical anchor for an elementary tree

60
A pro-Verb Story for Gapping
  • Like its anchor, the pro-V tree is defective
  • Cannot have contraction nodes?Gapping RNR,
    Gapping ATB movement
  • Depends on a bona fide verb for its
    interpretation (in some as yet unspecified
    structural relation)?Linearization, Restriction
    to coordination

61
Coordinated TPs and the CSC
  • Joe eats cookies and Sam drinks tea.

62
Coordinated TPs and the CSC
  • Who eats cookies and Sam drinks tea?
  • What rules out this derivation?

63
Coordinated TPs and the CSC
  • What (does) Joe eats cookies and?
  • What rules out this derivation?

64
Concluding Remarks
  • Linearization . . .
  • Requires a means to suppress conflicting
    information
  • Requires computation on the global structure
  • May choose between alternate analyses
  • Gapping is postulated to . . .
  • Involve a pro-V and an anaphoric dependency
  • CSC for coordinated TPs . . . ???

65
Acknowledgements
  • Bob Frank is gratefully acknowledged for his
    encouragement and guidance.
  • Thanks also to the Hopkins LingLab and Paul
    Smolensky for helpful feedback.
  • This work is supported by an NSF IGERT grant.

66
Thank you
67
Relating Coordination and Movement
A parallel between elements that can be extracted
and elements that can be coordinated (Dowty 1988).
68
Gapping
  • Tight match between antecedent and gap (cf)
    ellipsis.
  • identifying an active and passive VP
  • Ellipsis Botanist That can all be explained.
  • Mr. Spock Please do ____.
  • Gapping The budget cuts might be defended
    publicly by the chancellor, and the president
    might defend publicly her labor policies.
  • (Johnson 2003)

69
Gapping
  • Tight match between antecedent and gap (cf)
    ellipsis.
  • identifying an active and passive VP
  • an antecedent fashioned out of two VPs
  • Ellipsis Wendy is eager to sail around the world
    and Bruce is eager to climb Killimanjaro, but
    neither of them can ____ because money is too
    tight.
  • Gapping Wendy should sail the English Channel
    and Bruce climb Whitney, and their partners
    should sail and climb the Pacific or Killminjaro.

70
Gapping
  • Tight match between antecedent and gap (cf)
    ellipsis.
  • identifying an active and passive VP
  • an antecedent fashioned out of two VPs
  • an antecedent from inside a DP
  • Ellipsis ?Sal is a talented forger, but Holly
    cant ___ at all.
  • Gapping Sal may be a forger of passports and
    Holly may forge paintings.

71
Gapping
  • Tight match between antecedent and gap (cf)
    ellipsis.
  • identifying an active and passive VP
  • an antecedent fashioned out of two VPs
  • an antecedent from inside a DP
  • Restricted to coordination
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