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    Dialogue and Discourse

    analysis

    (some slides borrowed from

    D. Jurafski and from S.Ponzetto)

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    Natural Language Processing:leels of re!resentation

    Morphology

    Synta

    x

    Semantics

    Pragmatics

    Words"#

    "

    $

    %&

    D 'D

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    Meaning

    in context

    Processing flow of D&D Processing

    Sound

    waves&S#

    WordsSyntacti

    c!rocessi

    ng

    ParsesSemanti

    c!rocessi

    ng

    MeaningDiscourseDialog

    ue!rocessi

    ng

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    Discoursedialogue analysis

    So far we always analyzed onesentence in isolation syntacticallyandor semantically

    Natural languages are s!oken orwritten as a collection of sentences

    "n general a sentence or utterancecannot be understood in isolation.

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    & dialog e*am!le+u and #udnicky (,---)

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    A discourse example

    Jon went to te bank to de!osit is!ayceck.

    /e ten took a train to 0ill1s cardealersi!.

    /e needed to buy a car.

    2e com!any e works for now isn1tnear any !ublic trans!ortation.

    /e also wanted to talk to 0ill aboutteir softball league.

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    "ssues in discoursedialogue

    Dialogue2urn3taking

    S!eec act

    4rounding Dialogue management

    Discourse Segmentation coerence relations

    0ot &na!ora

    5o3reference

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    6. 2urn3taking

    Dialogue is caracterized byturn3taking.&:0:&:0:

    7 #esource allocation !roblem: /ow do s!eakers know wen to take te

    8oor9

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    2urn3taking rulesSacks et al. (6;#N32&?"N4 #$%>"#$S 2@ D$A"P#@2@5@L

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    "ssues in discoursedialogue

    Dialogue2urn3taking

    S!eec act

    4rounding Dialogue management

    Discourse Segmentation coerence relations

    0ot &na!ora

    5o3reference

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    ,. S!eec &cts

    S!eaker1s contribute more informationtan Bust Cwat is said

    S!eec &cts can gie a !rinci!ledaccount of additional meaning

    S!eec &ct 2eory can also el! use*amine utterances from te!ers!ectie of teir function ratertan teir form

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    5lassiEcation of S& according toCforce

    Locutionary Force (what is said)

    Bring the chair to the dining room

    Illocutionary Force (what is done)

    The robot is asked to grasp a chair andchange his current position

    Perlocutionary Force (the efect)

    The current position of the robot&chairchanges to dining room (if action issuccessfully performed)

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    2e F leels of act reisited

    LocutionaryForce

    IllocutionaryForce

    PerlocutionaryForce

    Can I have the restof your sandwich?OrAre you going tofinish that?

    Interrogative Stop eating thesandwich

    Effect: ou give !esandwich "or youare a!used #y !y$uoting fro!%&iner'( "or etc(

    I want the rest ofyour sandwich

    &eclarative Stop eating thesandwich

    Effect: as a#ove

    )ive !e yoursandwich*

    &irective Stop eating thesandwich

    Effect: as a#ove+

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    2y!es of S!eec acts (more Ene3grained)

    Commissives (Afect Speaer! Su"#ective)

    $%P&S' ath! fer! Promise

    I promise you a new book

    eclaratives (Change the *acrocosmic Social +orld)

    $%P&S' ,aptism! *arriage I will spend my vacations in ardinia

    irectives (Change the *icrocosmic Social +orld)

    $%P&S' Command! -e.uest

    !ove the chair near the table

    &xpressives (Feelings o/ Speaer) $%P&S' Apology! $hans

    orry" I did not understood correctly

    (*ey 012! Searle 0344! 56)

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    2y!es of S!eec acts (more Ene3grained)

    Interrogatives (7earer 8nows ,est)

    $%P&S' Closed (yes9no .uestions! list)! pen (who:when:;;) #o you see the co$e maker somewhere in the kitchen%

    Imperatives (irectives) (Afect 7earer)

    $%P&S' -e.uest! -e.uirement! $hreat! +arning o to the dining room

    Per/ormatives (Afect world)

    $%P&S' Agreement! Appointment! ,aptism! eclarationo/ Independence! edication! *arriage

    'ou are right

    -epresentatives ("#ective escriptive Statements)

    $%P&S' Statement that is either $rue or False

    The co$ee maker is on the table

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    >se of s!eec acts in dialogue:s!eec3act frames

    (Arost et al. ,-6-)

    ce "ythe lo""y!?

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    "ssues in discoursedialogue

    Dialogue2urn3taking

    S!eec act

    4rounding Dialogue management

    Discourse Segmentation coerence relations

    0ot &na!ora

    5o3reference

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    F. 4rounding

    Gy do eleator buttons ligt u!9

    5lark (6H) (after Norman 6II)

    rinciple of closure. &gents!erforming an action reuireeidence suKcient for current!ur!oses tat tey aesucceeded in !erforming it

    Gat is te Clinguistic correlate oftis9

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    4rounding

    Need to know weter an actionsucceeded or failed

    Dialogue is also an action a collective action !erformed by s!eaker and

    earer

    Common ground: set of tings mutuallybelieed by bot s!eaker and earer

    Need to aciee common ground soearer must groundor acknowledges!eakers utterance.

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    /ow do s!eakers ground95lark and Scaefer

    5ontinued attention: 0 continues attending to &

    #eleant ne*t contribution: 0 starts in on ne*t releant contribution

    &cknowledgement: 0 nods or says continuer like uh*huhyeah assessment

    (great)

    Demonstration: 0 demonstrates understanding & by !ara!rasing or

    reformulating &1s contribution or by collaboratielycom!leting &1s utterance

    Dis!lay: 0 dis!lays erbatim all or !art of &1s !resentation

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    & uman3umanconersation

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    4rounding e*am!les

    Dis!lay: 5: " need to trael in ay

    &: &nd wat day in aydid you want to

    trael9

    &cknowledgement 5: /e wants to 8y from 0oston

    &: mm3mm 5: to 0altimore Gasington "nternational

    Mm3mm (usually transcribed Cu3u) is

    abackcannel continuer or

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    4rounding $*am!les (,)

    &cknowledgement O ne*t releantcontribution &nd wat day in ay did you want to

    trael9 &ndyou1re 8ying into wat city9

    &ndwat time would you like to leae9

    2e andindicates to te client tatagent as successfully understoodanswer to te last uestion.

    4 di i

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    4rounding negatieres!onsesArom 5oen et al. (,--

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    4rounding and DialogueSystems 4rounding is not Bust a tidbit about

    umans

    Is ey to design o/conversational agent

    Gy9 /5" researcers End users of s!eec3

    based interfaces are confused wensystem doesn1t gie tem an e*!licitacknowledgement signal

    Stifelman et al. (6F) =ankeloic et al.

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    $*am!le

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    "ssues in discoursedialogue

    Dialogue2urn3taking

    S!eec act

    4rounding Dialogue management

    Discourse Segmentation coerence relations

    0ot &na!ora

    5o3reference

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    Dialogue management

    & dialogue system is Enalized to some !ur!ose (e.g.a 8igt reseration)

    >nlike for discourse analysis a structure must "e

    determined a9priori to guide the conversation Dialogue manager: Cforces te dialogue between

    user and system to follow one or more structures

    Aor s!eec dialogue systems most common

    a!!roaces are: Ainite state dialogue manager

    Arame and slot semantics

    &gent3based dialogue manager

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    Ainite3state dialoguemanagers

    System com!letely controls teconersation wit te user.

    "t asks te user a series of uestions

    "gnoring (or misinter!reting)anyting te user says tat is not adirect answer to te system1s

    uestions

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    Ainite State Dialogueanager

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    System forces te user to follow testructure

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    Ainite3state a!!roac

    Pros sim!le to write

    ery robust and uick

    Cons System direct entire conersation

    >ser actions ery limited

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    Frame-based Approach

    Frame-ased s!stem As"s t#e user $uestions to fill slots in a templatein order to

    perform a tas" %form-filling tas"

    Permits t#e user to respond more flexil! to t#e s!stem's

    prompts %see (xample ) *ecogni+es t#e main concepts in t#e user's utterance

    Example 1)

    System: What is your destination?

    User: London.

    System: What day do you want to

    travel?

    User: Friday

    Example 2)

    System: What is your destination?

    User: London on Friday around

    10 in the morning.

    System: I have the following

    onnetion !

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    ArameSlot semantics

    Sow me morning 8igts from 0oston to SAon 2uesday.

    S/@G:

    AL"4/2S:@#"4"N:

    5"2=: Boston

    D&2$: Tuesday

    2"$: morning

    D$S2:

    5"2=: San Francisco

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    Arameslot Semantics (multi!lesentences)

    Slot %uestion "D$N2"A= Gat is your name9

    @#"4"N Gat city are you leaing from9

    D$S2 Gere are you going9

    D$P2 D&2$ Gat day would you like to leae9

    D$P2 2"$Gat time would you like to leae9

    &"#L"N$ Gat is your !referred airline9

    e te structure of te frame itself to guide dialogu

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    Advantages ,#e ailit! to use natural language multiple

    slot filling

    ,#e s!stem processes t#e user's over-informative answers and corrections

    DisadvantagesAppropriate for well-defined tas"s in w#ic# t#e

    s!stem ta"es t#e initiative in t#e dialog Difficult to predict w#ic# rule is li"el! to fire in

    a particular context

    Arame3based a!!roaces

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    Properties .omplex communication using unrestricted natural language

    "i#ed$Initiative

    %o$operative pro&lem solving

    ,#eorem proving planning distriuted arc#itectures

    .onversational agents

    (xamplesUser:Im looking for a job in the Calais area. Are there any servers?

    System:No, there arent any employment servers for Calais. However, there is

    an employment server for Pase!Calais an an employment server for "ille.

    Are yo# intereste in one of these?

    Syste! atte!pts to provide a !ore co,operative response that !ight address the

    user-s needs+

    &gent3based a!!roaces

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    Agent-based Approach

    Advantages

    Suitale to more complex dialogues

    Mixed-initiative dialogues

    Disadvantages

    Muc# more complex resources and

    processing

    Sop#isticated natural language capailities .omplicated communication etween

    dialogue modules

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    5>3systems (@lym!us)

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    "ssues in discoursedialogue

    Dialogue2urn3taking

    S!eec act

    4rounding

    Dialogue management

    Discourse Segmentation

    coerence relations

    0ot &na!ora

    5o3reference

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    Discourse segmentation

    Separating a documentinto a linearseuence of subto!ics Aor e*am!le: scientiEc articles are segmented

    into &bstract "ntroduction etods #esults5onclusions

    Note: tis is a sim!liEcation Q a discoursemigt ae a more com!le* structure

    &!!lications: Summarization: summarize eac segmentse!arately

    "nformation #etrieal "nformation $*traction:

    &!!ly to an a!!ro!riate i.e. relevantsegment

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    Discourse segmentation

    $*am!le: ,6 !aragra! article calledtarga+ers

    Source: /earst (6;)

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    >nsu!erised DiscourseSegmentation

    @nsupervisedR uses no trainingdata

    2y!ically cohesion-based: segment

    te*t into subto!ics in wicsentences!aragra!s are cohesivewit eac oter

    Cohesion: use of linguistic deicesto establis links between te*tualunits

    Lexical Cohesion: use of same or

    similar (e.g. y!ernyms y!onyms

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    2e*tiling (/earst 6;)

    &n unsu!erised coesion basedalgoritm com!are adBacent blocks of te*t

    look for sifts in ocabulary

    2ree main ste!s

    2okenization Le*ical score determination

    0oundary identiEcation

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    2e*tiling (/earst 6;)sentence numbers

    erm freuency

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    2e*t2iling: Pre3!rocessing

    5onert te*t stream into terms (words)

    #emoe sto!3words $.g. Cte Ca Cof 7

    #educe eac word to its root form (in8ectionalmor!ology) Nouns: singular to !lural (s!orts 3 s!ort) Terbs: in8ected to base form (coming 3 come)

    Diide te*t into toen se.uences(pseudo*sentences)of eual lengt (say ,- words)

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    2e*t2iling: Pre3!rocessing

    5onert te*t stream into terms (words)

    #emoe sto!3words $.g. Cte Ca Cof 7

    #educe eac word to its root form (in8ectionalmor!ology) Nouns: singular to !lural (s!orts 3 s!ort) Terbs: in8ected to base form (coming 3 come)

    Diide te*t into toen se.uences(pseudo*sentences)of eual lengt (say ,- words)

    l

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    l

    sco

    rede

    t

    5om!ute lexical cohesion scoreateac ga!

    Similarity of te blocks before and afterte ga!

    $ac block is made of k !seudo3

    sentences 5osine similarity between te blocks1

    word ectors

    4a!

    l

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    l

    sco

    rede

    t

    5om!ute lexical cohesion scoreateac ga!

    Similarity of te blocks before and afterte ga!

    $ac block is made of k !seudo3

    sentences 5osine similarity between te blocks1

    word ectors

    4a!

    Similarity

    2 t2ili 0 d

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    2e*t2iling: 0oundaryidentiEcation 5om!ute te de!t scores of eac

    ga! Distance from te !eaks on bot sides:

    (a3b)O(c3b) &ssign segmentation if te de!t

    score is larger tan a boundary cutoU

    (e.g. ag3sd)ab

    calley

    2 t2ili 0 d

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    2e*t2iling: 0oundaryidentiEcation 5om!ute te de!t scores of eac

    ga! Distance from te !eaks on bot sides:

    (a3b)O(c3b) &ssign segmentation if te de!t

    score is larger tan a boundary cutoU

    (e.g. ag3sd)

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    2e*tiling (/earst 6;)

    Source:/earst

    (6nsu!erised based on cue !rases (or

    discourse markers) Su!erised based on discourse treebanks Q cf.

    te Penn Discourse 2reebank(tt!:www.seas.u!enn.eduZ!dtb)

    &utomatic 5oerence

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    &utomatic 5oerence&ssignment Sallow cue3!rase3based algoritm:

    6. "dentify cue !rases in a te*t

    ,. Segment te*t into discourse segmentsusing cue !rases

    F. &ssign coerence relations between

    consecutie discourse segments

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    Automatic co#erence assignment

    Ste! 6: identiEcation of cue !rases tat signalcoerence relations

    iscourse connectives: Cbecause CaltougCe*am!le Cwit Cand 7

    5onnecties are ambiguous Git its distant orbit ars e*ibits frigid weater

    conditions Ge can see ars wit an ordinary telesco!e

    >se some sim!le euristics e.g. ca!italization ofwit etc. or more com!le* disambiguationtecniues

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    Automatic co#erence assignment

    Ste! ,: segment te te*t into discoursesegments2y!ically sentences may suKce 0>2

    clauses are often more a!!ro!riate(S!orleder and La!ata ,--

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    "dentifying #S &utomatically(arcu 6)

    & su!erised !arser trained on a discoursetreebank - retorical structure trees and3annotated

    for retorical relations (##s)

    $lementary discourse units ($D>s) linked by##s Parser learns to identify Nucleus Satellite and

    teir ## Aeatures: Gordnet3based similarity le*ical

    structural

    >ses discourse segmenter to identifydiscourse units2rained to segment on and3labeled cor!us

    (5

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    "ssues in discoursedialogue

    Dialogue2urn3taking

    S!eec act

    4rounding Dialogue management

    Discourse Segmentation coerence relations

    0ot &na!ora

    5o3reference

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    "D$N2"A="N4 G/"5/

    *&$IS#$A$# 2@2/$ S&$(D"S5@>#S$) &$I$%

    2ask deEnition

    5ains of mentions in te*t

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    5ains of mentions in te*t(5@#$A$#$N5$ 5/&"N)

    2oni Jonson!ulls a ta!e measure across te front of wat wasonce a stately Tictorian ome.& dee! trenc now runs along its nort wall e*!osed wente ouselurced two feet oU itsfoundation during lastweek[s eartuake.@nce inside ses!ends nearly four ours measuring anddiagramming eac room in te I-3year3old ouse gateringenoug information to estimate wat it would cost to rebuild

    it.Gile seworks inside a tenant returns wit seeral friendsto collect furniture and cloting.@ne of te friends swee!s broken dises and sattered glassfrom a counterto! and starts to !ack wat can be salaged

    from te kitcen. (GSJ section of Penn 2reebankcor us

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    &na!ora \ 5oreference

    5@#$A$#$N2 not &N&P/@#"5 two mentions of same obBect in diUerent

    documents @bamawas interiewed last nigt.2e

    President..

    &N&P/@#"5 not 5@#$A$#$N2

    identity of sense: Jon bougt a sirt and 0illgot @N$ too

    Nominal ana!oric

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    Nominal ana!orice*!ressions

    #$AL$+"T$ P#@N@>NS: Jon bougt imself an amburger

    P#@N@>NS: DeEnite !ronouns: #oss bougt ]a radiometer ^ tree

    kilograms of after3dinner mints_ and gae ]it ^ tem_ toNadia for er birtday. (/irst 6I6)

    "ndeEnite !ronouns: Sally admired Sue1s Backet so segot one for 5ristmas. (4arnam ,--6)

    D$A"N"2$ D$S5#"P2"@NS:

    & man and a woman came into te room. 2e man satdown.

    $!itets: & man ran into my car. 2e idiot wasn1t lookingwere e was going.

    D$@NS2#&2"T$S:

    2om as been caugt so!lifting. 2at boy will turn out

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    Non3nominal ana!oric e*!ressions

    P#@3T$#0S: Daryel tinks like " do.

    4&PP"N4:

    Nadia brougt te food for te !icnic and Daryel `te wine.

    2$P@#&L #$A$#$N5$S: "n te mid3Si*ties free loe was ram!ant across

    cam!us. "t was ten tat Sue turned to Scientology.(/irst 6I6)

    L@5&2"T$ #$A$#$N5$S:

    2e 5urc of Scientology met in a secret roombeind te local 5olonel Sanders1 cicken stand.

    Sue ad er Erst dianetic e*!erience tere. (/irst

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    2y!es of ana!oric relations

    "dentity of #$A$#$N5$ #oss bougt ]a radiometer ^ tree kilograms of after3

    dinner mints_ and gae ]it ^ tem_ to Nadia for erbirtday.

    "dentity of S$NS$ Sally admired Sue1s Backet so se got one for

    5ristmas. (4arnam ,--6) (P&=5/$5? P#@N@>NS): 2e man wo gae is

    !ayceck to is wife is wiser tan te man wo gae itto is mistress. (?arttunen 6;H9)

    0@>ND ana!ora No "talian beliees tat Gorld 5u! referees treated is

    team fairly

    &SS@5"&2"T$ indirect ana!oric relations(Ybridging1)

    2e ouse 7. te kitcen

    &ssociatie ana!ora

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    &ssociatie ana!ora(a ty!e of 0#"D4"N4)

    2oni Jonson!ulls a ta!e measure across te front of wat wasonce a stately Tictorian ome.& dee! trenc now runs along its nort wall e*!osed wen te

    ouse lurced two feet oU itsfoundation during last week[seartuake.@nce inside ses!ends nearly four ours measuring anddiagramming eac room in te I-3year3old ouse gateringenoug information to estimate wat it would cost to rebuild it.Gile seworks inside a tenant returns wit seeral friends tocollect furniture and cloting.@ne of te friends swee!s broken dises and sattered glassfrom a counterto! and starts to !ack wat can be salagedfrom te kitcen.

    (GSJ section of Penn 2reebankcor us

    Not all Yana!oric1 e*!ressions

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    Not all ana!oric e*!ressionsalways ana!oric

    $*!leties "t is alf !ast two.2ere is an engine at &on

    Airst mention deEnites #eferences to isual situation(Ye*o!ora1) !ick tat u! and !ut it oer tere.

    "nter!reting ana!oric

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    "nter!reting ana!orice*!ressions

    "nter!reting (Yresoling1) an ana!orice*!ressions inoles at least treeas!ects:6. Deciding weter te e*!ression is in fact

    ana!oric

    ,. "dentifying its antecedent (!ossibly notintroduced by a nominal)

    F. Determining its meaning (cfr. identity ofsense s. identity of reference)

    (not necessarily taken in tis order)

    Aactors tat aUect te inter!retation

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    Aactors tat aUect te inter!retationof ana!oric e*!ressions

    Aactors: or!ological features (agreement)

    Syntactic information (0inding)

    Salience Le*ical and commonsense knowledge

    Distinction often made between

    5@NS2#&"N2S (must e.g. agreementin gender as:,ohn---he " the book---it)and P#$A$#$N5$S

    Su!erised learning for coreference

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    5lassiEcation2rain a classiEer to determine weter

    two mentions are coreferentor not

    coreferent

    .Israel/ will as0 the 1S to 2 .the 3ewish state/ 2 .Ira$i/4 +++

    coref 9

    notcoref 9

    coref 9

    Su!erised learning for coreferenceresolution

    Su!erised learning for coreference

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    5lustering !airwise coreferencedecisions

    Israel

    the Bewishstate

    its

    A #itterypu"lic

    5lustering&lgoritm

    Ira.

    Ira.i

    @S

    @nited States

    Ira.

    @SA

    M"srael

    will ask te >S

    Mte Jewis state

    M"rai

    ;;;

    coref

    not coref

    not

    coref

    Israel

    Su!erised learning for coreferenceresolution

    S t l A t

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    Soon et al. (,--6): Aeatures

    Aeatures >sed Number &greement Aeature: are i and B bot singular or

    bot !lural

    Semantic 5lass &greement Aeature: true if te sem classof i and B are te same or if one is te !arent of teoterX false or unknown oterwise

    4ender &greement Aeature: are i and B of te samegender based on designator (r.) or !ronoun

    0ot3Pro!er3Names Aeature: true if i and B are !ro!er

    names &lias Aeature: true if i is an alias of B or ice ersa

    &!!ositie Aeature: true if i or B is a !ro!er name and iand B are se!arated by a comma and no erb

    Soon et al (,--6): semantic class

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    Soon et al. (,--6): semantic classagreement

    P$#S@N

    A$&L$ &L$

    @0J$52

    D&2$@#4&N"&2"@N

    2"$ @N$= P$#5$N2

    L@5&2"@N

    S$5L&SS R true iU semclass(i) VR semclass(B) oriceersa

    S t l A t

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    Soon et al. (,--6): Aeatures

    $*am!le V"srael te Jewisstate

    Le*ical and commonsense

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    Le*ical and commonsenseknowledge

    Nominals te most common ty!e ofana!oric e*!ression

    ain source of errors wit nominals:

    lack of commonsense knowledge Semantics as been !ointed out as being

    releant since seminal work: 5f. e.g. 5arniak (6;F)X /obbs (6;I)

    Le*ical and commonsense

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    Le*ical and commonsenseknowledge: e*am!les

    Gic kind of semantics is useful forcoreference resolution9 synonymy relations

    i.e. diUerent e*!ressions used to refer tote same conce!t

    Synonymy relations and coreference

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    Synonymy relations and coreferenceresolution

    2oni Jonson !ulls a ta!e measure across te front ofwat was once Ma stately Tictorian ome.

    7..

    2e remainder of Mte ouseleans !recariouslyagainst a sturdy oak tree.

    to merge teir >.S. satellite 2T o!erations wit

    Primestar Partners Mte nation1s largest satellite 2Tcom!any sources familiar wit te inuiry say. M. . .

    2e slot is igly aluable because it is one of onlytree aailable in Mtis countryfrom wic a satellitecan beam 2T !rograms across most of Nort &merica

    simultaneously.

    Le*ical and commonsense

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    Le*ical and commonsenseknowledge: e*am!les

    Gic kind of semantics is useful forcoreference resolution9 instance*of relations

    i.e. tat an indiidual belongs to acertain class (e.g. @bama is an istanceof >.S. President Aido is an instance ofdog "taly is an istance of Nation)

    "nstantiation relations and

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    "nstantiation relations andcoreference resolution

    M2e A55 took Mtree s!eciEcactions regarding M&2'2. 0y a

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    Le*ical and commonsenseknowledge: e*am!les

    Gic kind of semantics is useful forcoreference resolution9 isa relations

    i.e. subsum!tion between conce!ts (catis3a feline car is3a eicle)

    Subsum!tion relations and

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    Subsum!tion relations andcoreference resolution

    MPetrie Stores 5or!oration Secaucus NJ said anuncertain economy and faltering sales !robablywill result in a second uarter loss and !era!s

    a deEcit for te Erst si* monts of Escal 6#&L L&N4>&4$ "S P$#T&S"T$

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    $7& &