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20151227CCFADL65•IDC58%202040ZB201122•—Nature2011.8Prof.OrenEtzioniTuringCenterUniversityofWashingtonIBMWatson•(Watson)2011IBM“”Jeopardy!“”KenBradExpertSystem1960199020002010IR-basedQAKB-basedQACommunityQABaseBallLUNARMACSYMAMASQUETRECTemplate-basedQASHRDLEIR-basedQA+CommunityQAKB-basedQAKnowledgeBase•••KB-basedQAKB-basedQAtypePersonLocationtypeage34(Int)typePersonLocationtypeage34(Int)()typePersonLocationtypeage34(Int)SELECTDISTINCT?xWHERE{?y?x.res:?y.}(DL)!e11e9e10e12e2e1e3e4!e7e5e6e8SimilarityThisTalk•()45min•••(DL)45min••End2End()typePersonLocationtypeage34(Int)SELECTDISTINCT?xWHERE{?y?x.res:?y.}SQLSPARQLPrologFunQL…λx.配偶(姚明，y)Λ出⽣地(y,x)LambdaCalculusDCS-TreeFun-QL…Lambda••Constants•Entities,Numbers,Functions•LogicalConnectors•dd•Quantification•dd•AdditionalQuantifiers•Count,Argmax,Argmin,……•LambdaExpression•dd∧,∨,¬,→∃,∀λx.state(x)∧borders(x,texas)entityfunctionvariablequantifierDependencyCompositionalSemanticTree(DCS-Tree)mostpopulouscityinCaliforniaargmax(λx.city(x)∧loc(x,CA),λx.population(x))SemanticsSyntaxThisexamplecomesfromPercyLiang’sSlidesin2011citypopulousmostinCaliforniaDependencyCompositionalSemanticTree(DCS-Tree)mostpopulouscityinCaliforniacitypopulousmostinCaliforniaSemantics:DCSTreeSyntaxThisexamplecomesfromPercyLiang’sSlidesin2011CityPopulationargmaxLOCCAX1111121CDependencyCompositionalSemanticTree(DCS-Tree)mostpopulouscityinCaliforniaSemantics:DCSTreeThisexamplecomesfromPercyLiang’sSlidesin2011RelationCityPopulationargmaxLOCCAX1111121CCity(a)Population(b)LOC(c,d)CA(e)a=cd=ea=bCity;11:Population;C:argmax;11:LOC;12:CADependencyCompositionalSemanticTree(DCS-Tree)ThisexamplecomesfromPercyLiangetal,2011mostpopulouscityinCaliforniaCity;11:Population;C:argmax;11:LOC;12:CAargmax(λx.city(x)∧loc(x,CA),λx.population(x))citySanFranciscoChicagoNewYorkBostonLosanglesCACaliforniaLOCSanFranciscoCaliforniaChicagoIllinoisLosangelesCaliforniaBostonMassachusettsPopulationSanFrancisco85wChicago280wLosangeles450wBoston64wConstraintSatisfactionProblem(CSP)112112••Lambda•DependencyCompositionalSemantics(DCS-Tree)•mostpopulouscityinCaliforniaLOC(x,CA)IsA(x,City)Population(y,x)City;11:Population;C:argmax;11:LOC;12:CAargmax(λx.city(x)∧loc(x,CA),λx.population(x))lambdaDCS-TreeWhatstatesbordersTexasλx.state(x)∧borders(x,texas)entityRelationKBRelationentitymentionrelationmentionrelationmentionWhichsoftwarehasbeendevelopedbyorganizationsfoundedinCalifornia,USA?softwaredevelopedbyorganizationsfoundedinCaliforniadbo:Softwaredbr:developerdbo:Companydbr:foundationPlacedbo:Californiadbo:Software,dbr:developer,dbo:Companydbo:Company,dbr:foundationPlace,dbo:California••organizationsfoundedinCaliforniadbo:Companydbr:foundationPlacedbo:CaliforniaWhichsoftwarehasbeendevelopedbyorganizationsfoundedinCalifornia,USA?1233XXX(Mention)(KB)•SemanticParsing•CombinatoryCategoricalGrammars[Zettlemoyer,1995]•“-”Shift-reduceDerivations[Zelle,1995]•SynchronousGrammars[Wong,2007]•HybridTree[Lu,2008]•CFGCFG-likeGrammars[Clarke,2010]•CYKCYK-likeGrammars[Liang,2011]CCG+••NewYork•NP•nyCCG+•-(Zettlemoyeretal.2005)WhatislargeststatebordersTexasargmax(λx.state(x)∧borders(x,texas),λx,size(x)statebordersbordersTexasstateborders……W(s)NP:texasN:λx.state(x)(S\NP)/NP:λx,λy.borders(y,x)……C(L)Zettlemoyeretal.2005•EM••Parser(Wongetal.2006)••EntityMention•QueryLog••…•PatternRelation•[subjmarriedtoobj]—spouse(subj,obj)••OpenIE[Berant,2013]wasborninPlaceOfBirth•PatternRelation•[subjmarriedtoobj]—spouse(subj,obj)•••SRLWordNetFrameNet.........•••ItissaidthatJanehasmarriedMrSmithspouse(x,y)?••••WhichsoftwarehasbeendevelopedbyorganizationsfoundedinCalifornia,USA?{California},{California,USA}California:{California_State},{California_Film}founded:{foundationPlace},{founder}developedby:{developer}{dbo:Software,dbr:developer,dbo:Company}{dbo:Software,dbr:foundationPlace,dbo:Company}•ProbabilisticCombinatoryCategoricalGrammars(PCCG)NewYork:NP:nyNewYork:NP:ny_movieNewYork:NP:ny_personborders:(S\NP)/NP:next_to(y,x)borders:(S\NP)/NP:located_in(y,x)Training••TrainingAlgorithmCouldweencodeformulaintotheprobabilisticmodel•MarkovLogicNetwork•TheseweightedformulasL(f,w){i}defineaprobabilitydistributionoversetsofpossibleworldsC.•Letydenoteapossibleworld,–thenp(y)isdefinedasfollows(,)1()exp(())iniiiicwLcCpywfyZφφφ∈∈=∑∑ExampleofanMLN())()(),(,)()(ySmokesxSmokesyxFriendsyxxCancerxSmokesx⇔⇒∀⇒∀1.15.1Cancer(A)Smokes(A)Smokes(B)Cancer(B)Supposewehavetwoconstants:Anna(A)andBob(B)ThisexamplecomesfromPoon’sSlidesin2009ExampleofanMLNCancer(A)Smokes(A)Friends(A,A)Friends(B,A)Smokes(B)Friends(A,B)Cancer(B)Friends(B,B)())()(),(,)()(ySmokesxSmokesyxFriendsyxxCancerxSmokesx⇔⇒∀⇒∀1.15.1Supposewehavetwoconstants:Anna(A)andBob(B)ExampleofanMLN())()(),(,)()(ySmokesxSmokesyxFriendsyxxCancerxSmokesx⇔⇒∀⇒∀1.15.1Supposewehavetwoconstants:Anna(A)andBob(B)Cancer(A)Smokes(A)Friends(A,A)Friends(B,A)Smokes(B)Friends(A,B)Cancer(B)Friends(B,B)ExampleofanMLN()()(),(,)()()xSmokesxCancerxxyFriendsxySmokesxSmokesy∀⇒∀⇒⇔1.15.1Supposewehavetwoconstants:Anna(A)andBob(B)Cancer(A)Smokes(A)Friends(A,A)