if this pair is a referential pair (refpalr(P,Q)) and a noncoreferential pair (neorefpair(P,Q)). A.1 defrees a refpatr ,:P,Q> as one in which P is a pronoun, Q'is a noun (either pronominal or nonpronominal), and P and Q are distinct. Rules B, C, D, E, and F provide a disjunctive statement of the conditions under which the non-coreference goal ncorefpair(P,Q) is satisfied, and so const,tute the core of the algorithm. Each of these rules concludes with a cut to prevent unnecessary backtracking which could generate looping.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "Rule B, together with B. I, identifies the conditions under which constraint I holds. In the following example sentences, the pairs consisting of the second and the first coindexed expressions in la-c (and in lc also the pair < T,'she'> ) satisfy nonrefdep(P,Q) by virtue of rule B. la. John i said that they i came. b. The woman i said that he i is funny. C. I i believe that she i is competent.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "\u2022 \" \u2022 ~, t, \u2022", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "The algorithm Identifies they, John > as a nonrefdep pair in la, which entails that 'they, cannot be taken as coreferential with John. However, (the referent of) \"John\" could of course be part of the reference set of 'they, and in suitable discourses LODUS could identify this possibility.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "Rule C states that
is a non-coreferential pl.~i.r, if it satisfies the pro ncom(P,Q) predicate.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "s holds under two conditions, corresponding to disjuncts C. 1.a-b and C.l.a,c-f. The first condition specifies that the pronoun P and its putative antecedent Q are both arguments of the same phrasal head, and so implements constraint II. This rules out referential dependence in 2a-b.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "2a. Mary i likes her i.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "b. She i tikes her i.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "Given the fact that Slot Grammar unifies the argument and adjunct variables of a head with the phrases which t'dl these variable positions, it will also exclude coreference in cases of control and unbounded dependency, as in 3a-c.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "3a. Jolt. seems to want to see hirn~.. b. Whi6h man i did he i see? -e. This is the girl i. Johh said she i saw.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "The second disjunct C.l.a,c-f covers cases in which the pronoun is an argument which is higher up in the head-argument structure of the sentence than a non-pronominal noun. This disjunct corresponds to condition IV. C.2-C.2.2 provide a reeursive definition of containment within aphrase. This definition uses the relation of immediate containment, eont i (P ,Q), as the base of the recursion, where con~ i (P ,Q) holds if Q is either an argument or an adj'unct (modifier or determiner) of a head Q. The second disjunct blocks coreference in 4a-c. 4a. He~ believes that the m.a% is amusing.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "b. Who i did he i say Johr~. hssed? c. This Is the man i he i said John i wrote about.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "The wh-phrase in 4b and the head noun of the relative clause in 4c unify with variables in positions contained within the phrase (more precise!y, the verb which heads the phrase) of which the pronoun is an argument. Therefore, the algorithm identifies these nouns as impossible antecedents of the pronoun.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "The two final conditions of the second disjunct, C. 1 .e and C. l.f, describe cases in which the antecedent of a pronoun is contained in a preceding adjunct clause, and cases in which the antecedent is the determiner of an NP which precedes a pronoun, respectively. These clauses prevent such structures from satisfying the noncoreference goal, and so permit referential dependence in 5a-b. 5a. After John i sang, he i danced.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "b. Johni's motherlikes him i.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "Notice that because a determiner is an adjunct of an NP and not an argument of the verb of which the NP is an argument, rule C. 1 also permits coreference in 6.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "6. His i mother likes John i.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "ltowever, C.l.a,c-e correctly excludes referential dependence in 7, where the pronoun is an argument which is higher than a noun adjunct.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE FILTER", "sec_num": "3." }, { "text": "The algorithm permits backwards anaphora in cases like 8, where the pronoun is not an argument of a phrase 14 to wtfich its antecedent Q bears the con t (Q, fl ) relation.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "8. After he i sang, John i danced.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "D-D.I block coreference between an NP which is the argument of a head H, and apronoun that is the object of a preposition heading a PP adjunct of 14, as in 9a-c. These rules implement constraint III. 9a. Sam. i spoke about him i.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "b. She i sat near her i. C. Who i did he i ask for?", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "Finally, E-E.I and F realize conditions V and VI, respectively, in NP internal non-coreference cases like 10a-c.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "10a. His i portrait of Jo .hnj. is interesting.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "b. JolL, i/s portrait of htrn i is interestmg. c. Hisi description of the portrait by John i is interesting.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "Let us look at three examples of actual lists of pairs satisfying the nonrefdep predicate which the algorithm generates for particular parse trees of Slot Grammar. The items in each pair are identified by their words and word numbers, corresponding to their sequential position in the stnng.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "When the sentence Who did John say wanted to try to find him? is ~ven to the system, the parse is as shown in Figure 1 above, and the output of the filter is:", "cite_spans": [], "ref_spans": [ { "start": 110, "end": 118, "text": "Figure 1", "ref_id": "FIGREF0" } ], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "Noncoref pairs: he.lO -who.l Coreference analysis time = ii msec.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "Thus < \"him','who' > is identified as a non-coreferential pair, while coreference between 'John' and 'him is allowed.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "In Figure 3 , the algorithm correctly lists < 'him ,'Bill > (6-3) as a non-coreferential pair, while permitting 'him' to take \"John' as an antecedent. In Fi~c~ure 4, it correctly excludes coreference between him and 'John' (he.6-John.1), and allows him to be referentially dependent upon \"Bill'. complement clause subiect, tlowever, in Figure 4 , the infinitival clause IS an adjunct of 'lectured' mid requires matrix subject control.", "cite_spans": [], "ref_spans": [ { "start": 3, "end": 11, "text": "Figure 3", "ref_id": "FIGREF0" }, { "start": 336, "end": 345, "text": "Figure 4", "ref_id": "FIGREF0" } ], "eq_spans": [], "section": "He i likes Johni's mother.", "sec_num": "7." }, { "text": "We will discuss three suggestions which have been made in the computational literature for syntactically constraining the relationship between a pronoun and its set of possible antece. dents intra-sententially.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "EXISTING PROPOSALS FOR CON-STRAINING PRONOMINAL ANAPHORA", "sec_num": "4." }, { "text": "The first is Hobbs (1978) Algorithm, which performs a breadth-first, left-to-right search of the tree containing the pronoun for possible antecedents. The search is restricted to paths above the first NP or S node containing the pronoun, and so the pronoun cannot be boundby an antecedent in its minimal governing category. If no antecedents are found within the same tree as the pronoun, the trees of the previous sentences in the text are searched in order of proximity. There are two main .difficulties with this approach. First, it cannot be applied to cases of control in infinitival clauses, like those given in Figures 3 and 4 , or to unbounded dependencies, like those in Figure 1 and in examples 3b-c and 4b-c, without significant modification. It makes this distinction by virtue of the differences between the roles of the two infinitival clauses in these sentences. In Fi~gtjre 3, the infinitival clause is a complement o1 \"expected, and this verb is marked for object control of the Second, the algorithm is inefficient in design and violates modularity by virtue of the fact that it computes both intra-sentential constraints on pronoriainal anaphora and inter-sentential antecedent possibilities each time it is invoked for a new pronoun in a tree. Our system computes the set ofpronoun-NP pairs for which coreference is syntactically excluded in a single pass on a parse tree. This set provides the input to a semanticpragmatic discourse module which determines anaphora by inference and preference rules.", "cite_spans": [], "ref_spans": [ { "start": 618, "end": 633, "text": "Figures 3 and 4", "ref_id": "FIGREF0" }, { "start": 680, "end": 688, "text": "Figure 1", "ref_id": "FIGREF0" } ], "eq_spans": [], "section": "EXISTING PROPOSALS FOR CON-STRAINING PRONOMINAL ANAPHORA", "sec_num": "4." }, { "text": "The other two proposals are presented in Correa (1988) , and in lngria and Stallard (1989) . Both of these models are implementations oI Chomsky's Binding theory which make use of Government Binding type parsers. They employ essentially the same strategy. This involves computing the set of possible antecedents of an anaphor as the NP s which c-command the anaphor within a minimal domain (its minimal govet:ning category). 2 The minimal domain of an NP is characterized as the first S, or the first NP without a possessive subiect, in which it is contained. The possible intra-sentential antecedents of a pronoun are the set of NP's in the tree which are not included within this minimal domain.", "cite_spans": [ { "start": 41, "end": 54, "text": "Correa (1988)", "ref_id": "BIBREF6" }, { "start": 75, "end": 90, "text": "Stallard (1989)", "ref_id": "BIBREF10" } ], "ref_spans": [], "eq_spans": [], "section": "EXISTING PROPOSALS FOR CON-STRAINING PRONOMINAL ANAPHORA", "sec_num": "4." }, { "text": "See Reinhart (1976) and (1983) for alternative definitions of c-command, and discussions of the role of this relation in determining the possibilities of anaphora. See Lappin (1985) for additional discussion of the connection between c-command and distinct varieties of pronominal anal3hora. See Chomsky (1981 Chomsky ( ), (1986a Chomsky ( ) and (1986b for alternative definitions of the notion 'government' and 'rain,real governing category'. This approach does sustain modularity by computing the set of possible antecedents for all pronouns within a tree in a single pass operation, prior to the application of inter-sentential search procedures. The main difficulty with the model is that because constraints on pronominal anaphora are stated entirely in terms of configurational relations of tree geometry, specifically, in terms of c-command and minimal dominating S and NP domains, control and unbounded dep endency structures can only be handled b~' aditional and fairly complex devices.", "cite_spans": [ { "start": 4, "end": 23, "text": "Reinhart (1976) and", "ref_id": null }, { "start": 24, "end": 30, "text": "(1983)", "ref_id": "BIBREF2" }, { "start": 168, "end": 181, "text": "Lappin (1985)", "ref_id": "BIBREF13" }, { "start": 296, "end": 309, "text": "Chomsky (1981", "ref_id": null }, { "start": 310, "end": 329, "text": "Chomsky ( ), (1986a", "ref_id": "BIBREF4" }, { "start": 330, "end": 352, "text": "Chomsky ( ) and (1986b", "ref_id": null } ], "ref_spans": [], "eq_spans": [], "section": "EXISTING PROPOSALS FOR CON-STRAINING PRONOMINAL ANAPHORA", "sec_num": "4." }, { "text": "It is necessary to generate empty categories for PRO and trace in appropriate positions in parse trees. Additional algorithms must be invoked to specify the chains of control (A-binding) for PRO, and operator (A )-binding for trace in order to link these categories to the constituents which bind them. The algorithm which computes possible antecedents for anaphors and pronouns must be formulated so that ii identifies the head of such a chain as non-coreferential with a pronoun or anaphor (in the sense of the Binding theory), if any element of the chain is excluded as a possible antecedent.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "EXISTING PROPOSALS FOR CON-STRAINING PRONOMINAL ANAPHORA", "sec_num": "4." }, { "text": "Neither empty categories nor binding chains are required in our system. In Slot Grammar parse representations, wh-phrases, heads of relative clauses, and NP's which control the subjects of inf'mitival clauses are unified with the variables corresponding to the roles they bind in argument positions. Tlierefore, the clauses of the algorithm apply to these constructions directly, and without additional devices or stipulations)", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "EXISTING PROPOSALS FOR CON-STRAINING PRONOMINAL ANAPHORA", "sec_num": "4." }, { "text": "We have recently implemented an algorithm for the interpretation of intrasentential VP anaphora structures like those in 1 la-c. 1 l a. John arrived, and Mary did too. b. Bill read every book which Sam said he did. c. Max wrote a letter to Bill before Mary did to John.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE INTEGRATION OF THE FILTER INTO OTHER SYSTEMS OF ANAPHORA RESOLUTION", "sec_num": "5." }, { "text": "The VP anaphora algorithm generates a second tree which copies the antecedent verb into the position of the head of the elliptical VP. It also lists the new arguments and adjuncts which the copied verb inhei'its from its antecedent. We have integrated our filter on pronominal anaphora into this algorithm, so that the filter applies to the interpreted trees which the algorithm generates. consider 12. John likes to him, and Bill does too.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE INTEGRATION OF THE FILTER INTO OTHER SYSTEMS OF ANAPHORA RESOLUTION", "sec_num": "5." }, { "text": "If the [dter applies to the parse of 11, it will identify only .< him, John'> as a non-coreferential pair, gwen that the pair <'him','Bill'> doesn t satisfy any of the conditions of the filter algorithm. Ilowever, when the filter is applied to the interpreted VP anaphora tree of 12, the filter algorithm correctly identifies both pronoun-NP pairs, as shown in the VP output of the algorithm for 12 given in Figure 5 . Coreference analysis time = 70 msec. Our filter also provides input to a discourse understanding system, LODUS, designed and implemented by A. Bernth, and described in (..Bernth 1988 (..Bernth , 1989 . LOI)US creates a single discourse structure from the analyses of the S|0t Grammar parser for several sentences. It interprets each sentence analysis in the context consisting of the discourse processed so far, together with domain knowledge, and it then embeds it into the discourse structure. The process of inte.rpretation consists in applying rules of inference which encode semantic and pragmatic (know-In fact, a more complicated algorithm with approximately tile same coverage as our lilter can be formulated fi, r a parser which produces configurational surlhce trees wiulout empty categories and binding chains, if the parser provides deep grammatical roles at some level of representation. The first author has implemented such an algorithm for the PEG parser. For a general description of I'EG, see Jensen (1986) . The current version of ['E(; provides information on deep grammatical roles by means of second pass rules which apply to the initial parse record structure. The algorithm employs both c-command and reference to deep grammatical roles. ledge-based) relations among lexical items, and discourse structures. The fdter reduces the set oI possible antecedents which the anaphora resolution component of LODUS considers for pronouns. For example, this component will not consider 'the cat or that' as a .p, ossible antecedents for either occurrence of it in the second sentence in 13, but only \"the mouse' in the first sentence of this discourse. This is due to the fact that our fdter lists the excluded pairs together with the parse tree of the second sentence.", "cite_spans": [ { "start": 587, "end": 601, "text": "(..Bernth 1988", "ref_id": null }, { "start": 602, "end": 618, "text": "(..Bernth , 1989", "ref_id": null }, { "start": 1430, "end": 1443, "text": "Jensen (1986)", "ref_id": "BIBREF11" } ], "ref_spans": [ { "start": 408, "end": 416, "text": "Figure 5", "ref_id": "FIGREF0" } ], "eq_spans": [], "section": "THE INTEGRATION OF THE FILTER INTO OTHER SYSTEMS OF ANAPHORA RESOLUTION", "sec_num": "5." }, { "text": "John", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE INTEGRATION OF THE FILTER INTO OTHER SYSTEMS OF ANAPHORA RESOLUTION", "sec_num": "5." }, { "text": "13. The mouse ran in.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE INTEGRATION OF THE FILTER INTO OTHER SYSTEMS OF ANAPHORA RESOLUTION", "sec_num": "5." }, { "text": "The cat that saw it ate it.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE INTEGRATION OF THE FILTER INTO OTHER SYSTEMS OF ANAPHORA RESOLUTION", "sec_num": "5." }, { "text": "Thus, the fdter significantly reduces the search space which the anaphora resolution component of LODUS must process. The interface between our filter and LODUS embodies the sort of modular interaction of syntactic and semantic-pragmatic components which we see as important to the successful operation and efficiency of any anaphora resolution system.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "THE INTEGRATION OF THE FILTER INTO OTHER SYSTEMS OF ANAPHORA RESOLUTION", "sec_num": "5." } ], "back_matter": [ { "text": "We are grateful to Arendse Bemth, Martin Chodorow, and Wlodek Zadrozny for helpful comments and advice on proposals contained in this paper.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "ACKNOWLEDGMENTS", "sec_num": null } ], "bib_entries": { "BIBREF0": { "ref_id": "b0", "title": "Computational Discourse Semantics, Doctoral Dmsertation, U. 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Stallard (1989) \"A Computa- tional Mechanism for Pronominal Reference\", Proceedings of the 27th Annual Meeting of the Association for Computational Linguistics, Vancouver, pp. 262-271.", "links": null }, "BIBREF11": { "ref_id": "b11", "title": "PEG: A Broad-Coverage Computatmnal Syntax of English", "authors": [ { "first": "K", "middle": [], "last": "Jensen", "suffix": "" } ], "year": 1986, "venue": "", "volume": "", "issue": "", "pages": "", "other_ids": {}, "num": null, "urls": [], "raw_text": "Jensen, K. (,1986) \"PEG: A Broad-Coverage Computatmnal Syntax of English,\" Technical Report, IBM T.J. Watson Research Center, Yorktown Heights, NY.", "links": null }, "BIBREF12": { "ref_id": "b12", "title": "Documentation of Features and Attributes in UDICT", "authors": [ { "first": "J", "middle": [ "L" ], "last": "Klavans", "suffix": "" }, { "first": "N", "middle": [], "last": "Wacholder", "suffix": "" } ], "year": 1989, "venue": "", "volume": "", "issue": "", "pages": "", "other_ids": {}, "num": null, "urls": [], "raw_text": "Klavans, J. L. and Wacholder, N. (1989) \"Doc- umentation of Features and Attributes in UDICT,\" Research Report RC14251, IBM T.J. Watson Research Center, Yorktown Heights, N.Y.", "links": null }, "BIBREF13": { "ref_id": "b13", "title": "Pronominal Binding and Coreference", "authors": [ { "first": "S", "middle": [], "last": "Lappin", "suffix": "" } ], "year": 1985, "venue": "", "volume": "", "issue": "", "pages": "241--263", "other_ids": {}, "num": null, "urls": [], "raw_text": "Lappin, S. (1985) \"Pronominal Binding and Co- reference\", Theoretical Linguistics 12, pp. 241-263.", "links": null }, "BIBREF14": { "ref_id": "b14", "title": "Slot Grammars", "authors": [ { "first": "M", "middle": [ "C" ], "last": "Mccord", "suffix": "" } ], "year": 1980, "venue": "Computational Linguistics", "volume": "6", "issue": "", "pages": "31--43", "other_ids": {}, "num": null, "urls": [], "raw_text": "McCord, M. C. (1980) \"Slot Grammars,\" Com- putational Linguistics, vol. 6, pp. 31-43.", "links": null }, "BIBREF15": { "ref_id": "b15", "title": "Design of LMT: A Prolog-based Machine Translation System", "authors": [ { "first": "M", "middle": [ "C" ], "last": "Mccord", "suffix": "" } ], "year": 1989, "venue": "", "volume": "", "issue": "", "pages": "", "other_ids": {}, "num": null, "urls": [], "raw_text": "McCord, M. C. (1989a) \"Design of LMT: A Prolog-based Machine Translation System,\"", "links": null } }, "ref_entries": { "FIGREF0": { "num": null, "uris": null, "text": "the lists of left modifiers and right modifiers, respectively. Each member of a modifier list is of the form Slot:Phrase where Slot is a slot and", "type_str": "figure" }, "FIGREF1": { "num": null, "uris": null, "text": "Q) ~ refpair(P,Q) & ncorefpair(P,Q). refpair(P,Q) ~ pron(p) & noun(Q) & P=/Q. ncorefpair(P,Q) ~ nonagr(P,Q) &/. nonagr(P,Q) ~ numdif(p,Q) I typedif(P,Q) I persdif(P,Q). ncorefpair(P,Q) ~ proncom(P,Q) (Q,T) I gt(Q,p)) & (~det(Q) I gt(Q,P))). cont_i(P,Q) ~ argm(P,Q) I adjunct(P,Q). cont(P,Q) ~ cont_i(P,Q). cont(P,Q) ~ cont_i(P,R) & R=/Q & cont(R,Q). subclcont(P,Q) ~ subconj(Q) & cont(P,Q). ncorefpair(P,Q) ~ prepcom(Q,P) &/. prepcom(Q,P) ~ argm(Q,H) & adjunct(R,H) & prep(R) & argm(P,R). ncorefpair(P,Q) ~ npcom(P,Q) &/. npcom(Q,P) ~ adjunct(Q,H) & noun(H) & (argm(P,H) [ adjunct(R,H) & prep(R) & argm(P,R)). ncorefpair(P,Q) ~ nppcom(P,Q) &/. nppcom(P,Q) ~ adjunct(P,H) & noun(H) & -pron(Q) & cont(Q,H).", "type_str": "figure" }, "FIGREF2": { "num": null, "uris": null, "text": "Figure 2.", "type_str": "figure" }, "FIGREF3": { "num": null, "uris": null, "text": "Figure 3.", "type_str": "figure" }, "FIGREF4": { "num": null, "uris": null, "text": "Figure 4.", "type_str": "figure" }, "FIGREF5": { "num": null, "uris": null, "text": "Figure 5.", "type_str": "figure" }, "TABREF1": { "content": "
| I | subj(n) top | John(X3) expect(Xl,X3,X4,X5) verb noun | |
| I | obj | Bill(X4) | noun |
| preinf | preinf(X5) | preinf | |
| comp(inf) impress(XS,X4,X6) | verb | ||
| obj | he(X6) | noun | |
| Noncoref pairs : | |||
| he.6 -Bill.3 | |||
| Coreference analysis time = 5 msec. |
| Antecedent Verb-Elliptical Verb Pairs. | |||
| like.2 -dol.7 | |||
| Elliptical Verb-New Argument Pairs. | |||
| like.7 -he.3 | |||
| Interpreted VP anaphora tree. | |||
| subj John(X9) | noun | ||
| ~ | iconj like(X8,X9,Xl0) | verb | |
| obj | he(Xl0) | noun | |
| \u2022 ~ subj BilI(XI2) top and(Xi,X8,Xll) rconj like(Xll,Xl2,Xl0) verb verb noun vadv too(Xll) adv | |||
| Non-Coreferential Pronoun-NP Pairs. | |||
| he.3 -John.l, he.3 -Bill.6 |