Unbounded Dependency Constructions _UDCs_ in HPSG From local to by ert634

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									                                                                                                  From local to non-local dependencies

      Unbounded Dependency Constructions (UDCs)
                     in HPSG
                                                                                     • A head generally realizes its arguments locally within its head domain.

                                                                                     • Certain kind of constructions resist this generalization, such as, for
                                                                                       example, the wh-questions discussed below.

                                       L614                                          • How can the non-local relation between a head and such arguments be
                                    Spring 2008                                        licensed? How can the properties be captured?




                                                                                 1                                                                               2




                      A first example: Wh-elements                                    Different categories can be extracted:

                                                                                      (3) a.   Which man did you talk to ?                                    NP
Wh-elements can have different functions:
                                                                                          b.   [To [which man]] did you talk ?                                PP

 (1) a.   Who    did Hobbs see ?                                   Object of verb
                                                                                          c.   [How ill ] has the man been ?                                 AdjP

     b.   Who    do you think saw the man?                        Subject of verb
                                                                                          d.   [How frequently] did you see the man             ?            AdvP

     c.   Who    did Hobbs give the book to ?                      Object of prep    This sometimes provides multiple options for a constituent:
     d.   Who    did Hobbs consider to be a fool?       Object of obj-control verb
                                                                                      (4) a. Who does he rely [on ]?
Wh-elements can also occur in subordinate clauses:                                        b. [On whom] does he rely ?

 (2) a.   I   asked   who   the man saw .                                            Unboundedness:
     b.   I   asked   who   the man considered to be a fool .
                                                                                      (5) a. Who do you think Hobbs saw ?
     c.   I   asked   who   Hobbs gave the book to .
                                                                                          b. Who do you think Hobbs said he saw ?
     d.   I   asked   who   you thought saw Hobbs.
                                                                                          c. Who do you think Hobbs said he imagined that he saw         ?
                                                                                 3                                                                               4




               Unbounded dependency constructions                                                                      Strong UDCs
                                                                                     An overt constituent occurs in a non-argument position:

An unbounded dependency construction                                                 Topicalization:
                                                                                      (6) Kimi, Sandy loves    i   .
  – involves constituents with different functions
  – involves constituents of different categories
                                                                                     Wh-questions:
  – is in principle unbounded                                                        (7) I wonder [whoi Sandy loves                   ].
                                                                                                                              i


                                                                                     Wh-relative clauses:
                                                                                     (8) This is the politician [whoi Sandy loves           i   ].
Two kind of unbounded dependency constructions (UDCs)
  – Strong UDCs                                                                      It-clefts:
  – Weak UDCs                                                                         (9) It is Kimi [whoi Sandy loves            i    ].

                                                                                     Pseudoclefts:
                                                                                     (10) [Whati Sandy loves       i   ] is Kimi.
                                                                                 5                                                                               6
                               Weak UDCs                                                          Some properties of UDC constructions


No overt constituent in a non-argument position:
                                                                                       Link between filler and gap with category information needed:
Purpose infinitive (for -to clauses):
(11) I bought iti for Sandy to eat      i   .                                          (15) a. Kimi, Sandy trusts i.
                                                                                            b. [On Kim]i, Sandy depends i.
Tough movement:                                                                        (16) a. * [On Kim]i, Sandy trusts i.
(12) Sandyi is hard to love     i   .                                                       b. * Kimi, Sandy depends i.

Relative clause without overt relative pronoun:
(13) This is [the politician]i [Sandy loves i ].

It-clefts without overt relative pronoun:
(14) It is Kimi [Sandy loves i ].

                                                                                   7                                                                         8




And this link has to be established for an unbounded length:                                                Using the feature slash
(17) a. Kimi, Chris knows Sandy trusts i.
     b. [On Kim]i, Chris knows Sandy depends i.
                                                                                       To account for UDCs, we will use the feature slash (so-named because it
(18) a. * [On Kim]i, Chris knows Sandy trusts i.
                                                                                       comes from notation like S/NP to mean an S missing an NP)
     b. * Kimi, Chris knows Sandy depends i.

(19) a. Kimi, Dana believes Chris knows Sandy trusts i.                                • This is a non-local feature which originates with a trace,
     b. [On Kim]i, Dana believes Chris knows Sandy depends i.
                                                                                       • gets passed up the tree,
(20) a. * [On Kim]i, Dana believes Chris knows Sandy trusts i.
     b. * Kimi, Dana believes Chris knows Sandy depends i.
                                                                                       • and is finally bound by a filler




                                                                                   9                                                                        10




                    An example for a strong UDC
                                        S
   f                                              h                                                    The bottom of a UDC: Traces
  NP                                              S
               c                                        h
 John i
                                                                                                                                     
                                                                                                     word
              NP                                       VP                                          phon                              
                                                                                                                                    
                           h                                   c                                          
                                                                                                            local 1
                                                                                                                                      
               we                                                                                  
                                                                                                   
                                                                                                                                      
                                                                                                                                     
                           V                                  S                                    synsem 
                                                                                                           
                                                                                                                   inherited|slash 1 
                                                                                                           nonloc                    
                                                      loc|cat|subcat                                               to-bind|slash {}
                         know               c                     h
                                        1 NP                       VP                  • phonologically null, but structure-shares local and slash values
                                                            loc|cat|subcat 1           • we’ll talk about to-bind later
                                            she
                                                         h                     c
                                                         V                 2 NP
                                            loc|cat|subcat 1 , 2                                                                                            12


                                                       likes                   i
                                Traces                                        The middle of a UDC: The Nonlocal Feature Principle
                                                                                                    (NFP)

Because the local value of a trace is structure-shared with the slash
value, constraints on the trace will be constraints on the filler.            For each nonlocal feature, the inherited value on the mother is the union
                                                                             of the inherited values on the daughter minus the to-bind value on the
• For example, hates specifies that its object be accusative, and this case   head daughter.
  information is local
• So, the trace has synsem|local|cat|head|case acc as part of its            • In other words, the slash information (which is part of inherited)
  entry, and thus the filler will also have to be accusative                    percolates “up” the tree

  (21) *Hei/Himi, John likes    i                                            • This allows the all the local information of a trace to “move up” to the
                                                                               filler



                                                                        13                                                                                                      14




         The top of a UDC: Filler-head structures                                          The top of a UDC: Filler-head structures
                          Filler-head schema                                                              Explanation of the schema


phrase
                      →                                                      • Filler and trace are identified as the exact same thing (as far as their
dtrs head-filler-struc
                                                                               local structure is concerned)
                                                                   
                                              verb                           • The trace is “bound” by the to-bind feature; this prevents the slash
                                     head                       
                       loc|cat               vform fin                        value from going any higher in the tree
                                                      
                                                               
                                                                  
                                       subcat
                       
     head-dtr|synsem 
                                                                 
                                                                         • Only saturated finite verbs (i.e., sentences) license such structures
                                                                  
                                        inherited|slash element 1 
                      
                         nonloc
                                                                 
     
                                       to-bind|slash    1
                                                                   
                                                                   
       filler-dtr|synsem|local 1



                                                                        15                                                                                                      16




                                                                                             The analysis of the strong UDC example
                                                                                                                               S
                                                                                                                 ˆ                       ˜
                                                                                                                  nloc|inherited|slash {}
                                                                                         f                                              h
         The top of a UDC: Filler-head structures
                                                                                        NP                                              S
     Example for a structure licensed by the filler-head schema                                                      "         "               ˘ ¯##
                                                                                                                               inherited|slash 3
                                                                                   ˆ             ˜
                                                                                       local 3
                                                                                                                      nloc                    ˘ ¯
                                                                                                                               to-bind|slash   3
                                                                                       Johni         c                                       h
                                                                                                     NP                                     VP
                                                                                                                          "     "               ˘ ¯##
                       nloc|inherited|slash {}                                                                             nloc
                                                                                                                                 inherited|slash 3
                                                                                                     we                          to-bind|slash {}
                                                                                                           h                                      c
           f                           h                                                                   V                                       S
                                                                                                                                   2                          3
                                                                                                                                       loc|cat|subcat
        local 1              inherited|slash . . . , 1 ,. . .                                                                               "              ˘ ¯#
                        nloc                                                                              know
                                                                                                                                   6
                                                                                                                                   4
                                                                                                                                       nloc
                                                                                                                                            inherited|slash 3 5
                                                                                                                                                               7

                             to-bind|slash   1                                                                                              to-bind|slash {}
                                                                                                                     c                                  h
                                                                                                                    1 NP                                VP
                                                                                                                                            2               ˙ ¸       3
                                                                                                                                             loc|cat|subcat 1
                                                                                                                                                  "                  #
                                                                                                                                                                  ˘ ¯7
                                                                                                                    she                            inherited|slash 3 5
                                                                                                                                            6
                                                                                                                                             nloc
                                                                                                                                            4
                                                                                                                                                   to-bind|slash {}
                                                                                                                                            h                             c
                                                                                                                           "
                                                                                                                                            V                         NP
                                                                                                                                          ˙      ¸ #          "                   #
                                                                                                                            loc|cat|subcat 1 , 2               loc 3
                                                                        17                                                                                   2                 ˘ ¯
                                                                                                                            nonloc|to-bind|slash {}            nloc|inher|slash 3


                                                                                                                                          likes                           i
                                          The analysis of weak UDCs                                                                                                   Lexical entry of adjective easy


          (22) a.        Kimi is easy (for John) to please i                                                                                      2
                                                                                                                                                    phon    <easy>
                                                                                                                                                                                                                                      3

               b.        Kimi is easy to prove that Mary asked Paul to bribe                                                i.
                                                                                                                                                            2    2      2                                                          3337
                                                                                                                                                                            headadj
                                                                                                                                                  6
                                                                                                                                                  6                                                                                   7
                                                                                                                                                  6         6                           “ ˆ ˜ ”                                   + 777
          (23) a.        It is easy to please himacc / * henom .
                                                                                                                                                                 6     6        *                                                  7 77
                                                                                                                                                  6
                                                                                                                                                  6
                                                                                                                                                            6
                                                                                                                                                            6    6cat 6           NP 1 , PP for 3 ,                                7777
                                                                                                                                                                       4subcat
                                                                                                                                                  6         6    6     6            h                       “                 ”i 7777
                                                                                                                                                                                                                                   5777
               b.        Inom am easy to please acc.
                                                                                                                                                                 6                                                ˆ ˜
                                                                                                                                                                                  VP inf, inher|slash element 2 NP acc :ppro 1 : 4 777
                                                                                                                                                  6         6    6
                                                                                                                                                  6         6
                                                                                                                                                  6         6loc 6
                                                                                                                                                                 6     2          3
                                                                                                                                                                                                                                    777
                                                                                                                                                                                                                                    777
                                                                                                                                                  6synsem                easy
                                                                                                                                                  6         6    6                                                                  777
                                                                                                                                                            6    6                                                                  777
                                                                                                                                                  6         6          6arg1 ref7
          ⇒ No true (non-argument) filler, only coindexed items serving as arguments
                                                                                                                                                                 6                                                                  777
                                                                                                                                                  6         6                 1 7
                                                                                                                                                                 6cont 6
                                                                                                                                                  6         6    6     6                                                            777
                                                                                                                                                                                                                                    777
                                                                                                                                                                       4arg2 3 5
                                                                                                                                                  6         6                     7
                                                                                                                                                  6         6    4                                                                  577
                                                                                                                                                                         arg3 4
                                                                                                                                                  6         6                                                                        77
                                                                                                                                                  4         4                                                                        55
                                                                                                                                                                                 ˘ ¯
          Subject is role assigned:                                                                                                                          nonloc|to-bind|slash 2
          (24) a. I believe there to be a unicorn in the garden.
                                                                                                                                                ⇒ Lexical entry selects for infinitive complement missing an NP, which is
               b. * There is easy to believe a unicorn in the garden.
                                                                                                                                                coindexed with the subject
          (25) a. [This sonata]i is easy to play i on that violin.
               b. [This violin]i is easy to play this sonata [on i].

                                                                                                                                          19                                                                                              20




                                              A weak UDC analysis
                                                                   VP
                                                         ˆ                       ˜
                                                          loc|cat|subcat
                   c                                                        h                                                                           Multiple traces with strong and weak UDCs
               3 NP 1                                                   VP
                                                             h                       ˙ ¸i
                                                                 loc|cat|subcat       3
                   Ii           h                                                    c
                                                                                                                                                (26) This is a problem which1 John2 is easy to talk to                2   about   1.
                                V                                                    AP
                                                                  "              ˙ ¸       #
                                                                   loc|cat|subcat 3
                                                                                                                                                This is analyzed by allowing slash to be a set value and binding each trace
                                                                        ˆ                 ˜
                                am                                 nloc inherited|slash {}
                                            h                                                       c                                           off in turn
                                 "
                                            A                                           4 VP[inf ]
                                                 ˙     ¸ #                      "               ˙ ¸     #
                                  loc|cat|subcat 3 , 4                           loc|cat|subcat 5
                                                     ˘ ¯
                                  nloc|to-bind|slash 2
                                                                                                     ˘ ¯
                                                                                 nloc|inherited|slash 2
                                                                                                                                                • easy binds trace2
                                                                  h                                                c
                                           easy                                                                                                 • The head-filler construction at the top of the tree binds trace1
                                                             V[inf ]                                          VP[bse]
                                                                                            "               ˙ ¸     #
                                                                                             loc|cat|subcat 5
                                                                                                                 ˘ ¯
                                                                                             nloc|inherited|slash 2
                                                                 to
                                                                                            h                                      c

                                                                            "
                                                                                          V[bse]                                 6 NP 1
                                                                                           ˙      ¸ #                  "                   #
                                                                             loc|cat|subcat 5 , 6                       loc 2
                                                                                                                                        ˘ ¯                                                                                               22
                                                                             nonloc|to-bind|slash {}                    nloc|inher|slash 2


                                                                                          please                                    i




                                           Multiple traces example                                                                                                   Limiting the occurrence of traces

                                                  2
                                                                   AP
                                                                    D    E     3
                                                      loc|cat|subcat 4 1
                                                  4        h               ˘ ¯5
                                                      nloc inherited|slash 3
                                                                              i
                                                                                                                                                The that-trace effect, one of the island effects:
              h                                                                  c
                                                                                                                                                (27) Whoi did he claim that she kissed i
              A                                                              VP[inf ]
h
    nloc|to-bind|slash
                         ˘ ¯i
                          2
                                                             h
                                                                 nloc|inherited|slash
                                                                                               ˘
                                                                                                   2,3
                                                                                                         ¯i
                                                                                                                                                (28) * Whoi did he claim that i kissed her.
                                     h                                                        c
            easy                                                                                                                                The trace principle (for English)
                                V[inf ]                                                   VP[bse]
                                                                        h                            i
                                                                                                                                                Every trace must be strictly subcategorized by a substantive head, i.e.,
                                                                                             ˘      ¯
                                                                         nloc|inherited|slash 2 , 3
                                    to             h                                      c                                         c           its synsem value must be a non-initial member of a substantive head’s
                                                   V                                      PP                                       PP           subcat list.
                                                                        h                           n         oi        h                ˘ ¯i
                                                                            nloc|inher|slash             21              nloc|inher|slash 3
                                                                                                                                                → That is, traces should be arguments (subcategorized) and they should not
                                                  talk
                                                                                      to                                      about             be subjects (strictly) ... Other languages may just require subcategorization

                                                                                                                                          23                                                                                              24
                             Subject extraction

                                                                                                           Subject extraction lexical rule (SELR):
But subjects can be extracted out of embedded clauses
                                                                                                           "                                                  #
                                                                                                            word
                                                                                                                                                “ ˆ
                                                                                                            synsem|local|cat|subcat|rest element S unmarked
                                                                                                                                                            ˜”    →
(29) * Whoi did he claim that i kissed her.                                                                                2         2                             0                          133
                                                                                                                                                                               VP D
(30) Whoi did he claim i kissed her.                                                                                       6
                                                                                                                           6
                                                                                                                                     6                              "               ˆ      ˜E# 77
                                                                                                                                     6local|cat|subcat|rest elementB loc|cat|subcat loc 1 C77
                                                                                                                           6synsem
                                                                                                                           6         6                             @                          A77
                                                                                                                           4
                                                                                                                                     6
                                                                                                                                     4                               nonloc|inher|slash {}     77
                                                                                                                                                                                               55
⇒ So, we treat subject extraction in a special, traceless manner, allowing                                                                                   ˘ ¯
                                                                                                                                       nonloc|inherited|slash 1
it to happen only in embedded clauses
                                                                                                           With the modifications in chapter 9, this will of course be reformulated as
                                                                                                           a rule applying to subj, not subcat




                                                                                                      25                                                                                       26




                        A subject extraction analysis
                                           S

      f                                            h                                                                                     Island constraints
     NP                              2
                                                   S              3
ˆ
    local 1
              ˜                              |subcat
                                      loc|cat"
                                                              ˘ ¯#
                                               inherited|slash 1 5
                                     6                            7
                                      nonloc
                                     4
     who                                       to-bind|slash
                                                              ˘ ¯
                                                               1                                           With the definition of strict subcategorization in the Trace Principle, certain
                  h             c                                  c                                       island constraints are correctly predicted.

                  V           3 NP                                VP                                       (31) a. How tall do you think the building is ?
                                                   "              ˙ ¸        #
                                                    loc|cat|subcat 3
                                                                          ˘ ¯
                                                    nonloc|inherited|slash 1
                                                                                                                b. *How do you think the building is tall? (modifier)
                  did          he
                                          h                                         c                      (32) a. That is the building [whose design our architects rejected ].
                                          V                                 2 VP[fin]                            b. *That is the building [whose our architects rejected [ design]].
                                                                                                                   (not strict)
                             "              ˙      ¸    #        h               D        ˜Ei
                              loc|cat|subcat 3 , 2
                                                                                  ˆ
                                                     ˘ ¯           loc|cat|subcat local 1
                              nonloc|inherited|slash 1
                                                                   h                            c
                                        claim                                                              (33) a. The books that I like, Leslie donated to the library.
                                                                V[fin]                          4 NP             b. *The books, Leslie donated [ that I like] to the library. (head)
                                                  h                    Dˆ          ˜      Ei
                                                      loc|cat|subcat        local 1 , 4


                                                                kissed                         her                                                                                             28




                    Multiple unbounded dependencies                                                                   Multiple unbounded dependencies (cont.)



(34) a. It will be easy to play even the most difficult sonata on a violin                                   (36) That was the rebel leader who1 rivals of              1   shot   1.
        this well crafted.
     b. [A violin this well crafted ]1, even [the most difficult sonata]2 will                               An example like this is handled rather smoothly because slash is a set-
        be easy to play 2 on 1.                                                                            valued feature, and so the two traces can be identified as the same.

(35) a. It is easy to talk to John about this topic.                                                       What distinguishes the following, however?
     b. This is the topic which1 John2 is easy to talk to                          2   about   1.
                                                                                                           (37) a. *That was the rebel leader who1 rivals of 1 shot the British
                                                                                                                   consul.
• Traces are bound at different points in the tree (as we saw earlier)                                           b. That was the rebel leader who1 agents of foreign powers shot 1.
• There are also cases, on the other hand, where traces are bound in unison


                                                                                                      29                                                                                       30
                                   Parasitic gaps                                                       Capturing parasitic gaps

Extraction out of objects is possible in English:
                                                                               The subject condition
(38) Who did John assassinate [rivals of        ]?
                                                                               The initial element of a lexical head’s subcat list may be slashed only if
                                                                               that list contains another slashed element.
Extraction out of subjects, however, is only possible in the presence of a
second gap:
                                                                               • All parasitic gaps are contained within subjects.
(39) Who did [rivals of ] assassinate ?
(40) a. * Who did [rivals of ] assassinate the President?                      • Any subject gap must be licensed by a gap from the same subcat list.
     b. Who did [rivals of the president] assassinate ?

The first trace is thus parasitic on the second one


                                                                          31                                                                           32




                    Summary of HPSG trace theory                                                              Traceless extraction



1. Nonlocal Feature Principle: For each nonlocal feature, the inherited        • Traces seem a little inelegant for HPSG
   value on the mother is the union of the inherited values on the
   daughter minus the to-bind value on the head daughter.                      • Remember that the revised HPSG (ch. 9) uses the valence features spr,
                                                                                 subj, comps.
2. Trace Principle (English): Every trace must be strictly subcategorized by
   a substantive head, i.e., its synsem value must be a non-initial member     • But we also retain subcat as a lexically-appropriate feature
   of a substantive head’s subcat list.
                                                                               Traceless extraction can proceed by moving an item off of subj or comps,
3. Subject Condition (English): The initial element of a lexical head’s        but keeping track of it on subcat.
   subcat list may be slashed only if that list contains another slashed
                                                                               Thus, slash originates not on a trace, but on the head that licenses the
   element.
                                                                               missing element.

                                                                          33                                                                           34




          Complement Extraction Lexical Rule (CELR)                                                          Lexical Rule in Action


                                                                               Extracting the second object of a double object verb (like give):
2       ˙           ¸    3
 subcat ..., 3 ,...
       D              ˜ E7
                             →
6            ˆ
6comps ..., 3 loc 1 ,... 7                                                     2       ˙         ¸       3
                                                                                subcat 1 , 2 , 3
4                        5
 inher|slash 2                                                                      ˙    ¸
                                                                                subj 1 N”
                                                                               6                         7
                                                                                                             →
                                                                               6                         7
                                                                               6      D                 E7
2       *      "               # +3                                            6comps 2 N”, 3 N”ˆloc 4 ˜ 7
                 loc 1                                                         4                         5
6subcat ..., 4              ˘ ¯ ,... 7                                          inher|slash {}
6                inher|slash 1       7
6      ˙       ¸                     7
4comps ... ...
6                                    7                                         2         *   "               #+3
                                                                                               loc 4
                                     5
              ˘ ¯
 inher|slash 1 ∪ 2                                                             6subcat 1 , 2 ,            ˘ ¯ 7
                                                                               6               inher|slash 4   7
                                                                               6                               7
                                                                               6subj ˙ 1 ¸                     7
                                                                               6        ˙  ¸                   7
                                                                               6                               7
                                                                               4comps 2 N”                     5
                                                                                            ˘ ¯
                                                                                inher|slash 4


                                                                               (41) books I know you gave Kim

                                                                          35                                                                           36
              Subject Extraction Lexical Rule (SELR)                                  Adjunct Extraction Lexical Rule (AELR)

"    ˙ ¸                      #                                          "     D               ˜ E#
 subj Y”
                                                                                         ˆ
                                                                          comps ..., 2 V” subj , ...
      D       ˆ        ˜ E        →                                                                    →
 comps ..., X” unmarked , ...                                             inher|slash {}

2                                                                        2                         3
       D     h    ˙     ¸i E3                                                   ˙
                                                                          comps ..., 2 ,...
                                                                                            ¸
 comps ...,X” subj loc 2 ,...                                            6              n ˆ   ˜ o7
4           ˘ ¯               5                                          6inher|slash Y” mod 2 : 3 7
 inher|slash 2                                                           4                         5
                                                                          content|soa-arg 3
Note that this rule is more indirect than CELR, in that we license the
extraction of a subject from an item on a complement list                And then there need to be further semantic/pragmatic constraints to allow
                                                                         extracted adjuncts in only certain sentences.




                                                                    37                                                                          38

								
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