台大-李宏毅-B站机器学习视频-课件神经网络与深度学习Structured Introduction

IntroductionofStructuredLearning,Hung-yiLee,StructuredLearning,WeneedamorepowerfulfunctionfInputandoutputarebothobjectswithstructuresObject:sequence,list,tree,boundingbox,Xisthespaceofonekindofobject,Yisthespaceofanotherkindofobject,Inthepreviouslectures,theinputandoutputarebothvectors.,ExampleApplication,SpeechrecognitionX:Speechsignal(sequence)Y:text(sequence)TranslationX:Mandarinsentence(sequence)Y:Englishsentence(sequence)SyntacticParingX:sentenceY:parsingtree(treestructure)ObjectDetectionX:ImageY:boundingboxSummarizationX:longdocumentY:summary(shortparagraph)RetrievalX:keywordY:searchresult(alistofwebpage),UnifiedFramework,UnifiedFrameworkObjectDetection,TaskdescriptionUsingaboundingboxtohighlightthepositionofacertainobjectinanimageE.g.AdetectorofHaruhi,Image,BoundingBox,Haruhi,(thegirlwithyellowribbon),UnifiedFrameworkObjectDetection,x:Image,y:BoundingBox,F(x,y),thecorrectnessoftakingrangeofyinxas“Haruhi”,F(x,y),UnifiedFrameworkObjectDetection,Enumerateallpossibleboundingboxy,inputx=,F(x,y),10,3,2,-1,(outputresult),UnifiedFramework-Summarization,TaskdescriptionGivenalongdocumentSelectasetofsentencesfromthedocument,andcascadethesentencestoformashortparagraph,longdocument=s1,s2,s3,si,summary=s1,s3,s5,si:theithsentence,UnifiedFramework-Summarization,Training,Inference,F(x,y),F(x,y),UnifiedFramework-Retrieval,TaskdescriptionUserinputakeywordQSystemreturnsalistofwebpages,(keyword),d10011,“Obama”,d98776,Alistofwebpages(SearchResult),UnifiedFramework-Retrieval,Training,Inference,F(x,y),F(x,y),x=“Haruhi”,y=,d203d330,x=“Haruhi”,y=,d103d304,x=“Haruhi”,y=,d103d305,UnifiedFramework,Statistics,Statistics,Probabilitycannotexplaineverything,0-1constraintisnotnecessary,Strengthforprobability,Drawbackforprobability,Meaningful,UnifiedFramework,Energy-basedModel:/yann/research/ebm/,UnifiedFramework,Therearethreeproblemsinthisframework.,Thatsit!?,Problem1,Evaluation:WhatdoesF(x,y)looklike?HowF(x,y)computethe“compatibility”ofobjectsxandy,F(x=,y=),F(x=,y=),(ashortparagraph),(keyword),(SearchResult),ObjectDetection:,Summarization:,Retrieval:,(alongdocument),F(x=“Obama”,y=),Problem2,Inference:Howtosolvethe“argmax”problem,ThespaceYcanbeextremelylarge!,ObjectDetection:,Summarization:,Y=Allpossibleboundingbox,Y=Allcombinationofsentencesetinadocument,Retrieval:,Y=Allpossiblewebpageranking.,(maybetractable),Problem3,Training:Giventrainingdata,howtofindF(x,y),Trainingdata:,Principle,WeshouldfindF(x,y)suchthat,forall,ThreeProblems,Haveyouheardthethreeproblemselsewhere?,From數位語音處理,LinktoDNN?,DNN,Training,Inference,F(x,y),Inhandwritingdigitclassification,thereareonly10possibley.,y=1000,y=0100,y=0010,Findmax,Thesameaswhatwehavelearned.,Youhavetoknow,ViterbiAlgorithm數位語音處理:.tw/DSP2015Autumn/V