Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social...

46
Graph Representation Learning with Hierarchical Structure and Domain Adaptation Speaker Lun Du Affiliation: Microsoft Research Asia 2019/10/11 Graph Representation Learning 1

Transcript of Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social...

Page 1: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

GraphRepresentationLearningwithHierarchicalStructureandDomainAdaptation

Speaker:LunDuAffiliation:MicrosoftResearchAsia

2019/10/11 GraphRepresentationLearning 1

Page 2: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

MainContents

q Background

q Graphembeddingwithhierarchicalcommunitystructure

q Domainadaptivegraphembedding

q Futureworks

2019/10/11 GraphRepresentationLearning 2

Page 3: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Background

q GraphEmbeddingtriestomapgraphverticesintoalow-dimensionalvectorspaceundertheconditionofpreservingdifferenttypesofgraphproperties.

2019/10/11 GraphRepresentationLearning 3

p Node classification

p Link Predictionp Network Visualization

p Community detection

p …...

Page 4: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Background

q Unsupervisedvs.Supervised§ DeepWalk,LINE, node2vec,etc.

§ GCN,GraphSAGE,etc.

q Euclideanvs.Non-Euclidean§ Hyperbolicspace(Tag2Vec,WWW’19)

q Vectorvs.Distribution§ Usingvariancetomodeluncertaintyofsemantic

2019/10/11 GraphRepresentationLearning 4

Page 5: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

MainContents

q Background

q Graphembeddingwithhierarchicalcommunitystructure

q Domainadaptivegraphembedding

q Futureworks

2019/10/11 GraphRepresentationLearning 5

Page 6: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Outline

q Conceptually,complexnetworkshavehierarchicalcommunity inrealworld.§ E.g.socialnetworks,airtransportationnetworks,andmetabolicnetworks,

etc.

2019/10/11 GraphRepresentationLearning 6

Page 7: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Outline

q HierarchicalInfocanbeobservedtoacertainextentinonlinenetworks.

2019/10/11 GraphRepresentationLearning 7

Explicit hierarchy with attributes Implicit hierarchy with tags

#

#University

#Major

#EnrollmentYear

TwitterNetworkFacebook Network

Page 8: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Outline

q Goal:§ Encodingtherichhierarchicalstructuralinformation

qMainChallenges:§ Howtorepresentnodesortags?

§ Howtolearntherepresentationseffectivelyandefficiently?

2019/10/11 GraphRepresentationLearning 8

Page 9: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

GalaxyNetworkEmbedding:AHierarchicalCommunityStructurePreserving

Approach

LunDu,Zhicong Lu,YunWang,GuojieSon𝑔∱ ,YimingWang,WeiChen.GalaxyNetworkEmbedding:AHierarchicalCommunityStructurePreservingApproach.InProceedingsofIJCAI,2018.

2019/10/11 GraphRepresentationLearning 9

Page 10: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

HowtoRepresent?

q Inspiredbygalaxystructureq Embeddingnodesandcommunitiessimultaneously

§ Easytoanalyzethenetworkatdifferentscales.

2019/10/11 GraphRepresentationLearning 10

(The representations of nodes in tree)

Embedding

Page 11: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

HowtoLearn?

q Formulatethehierarchicalcommunitypreservingnetworkembedding§ Oneisthelocalinformation,i.e.pairwisenodessimilarityinthesame

community.

§ Theotheristhehierarchicalstructureproperty,i.e.horizontalrelationshipandverticalrelationship.

q Implementandoptimizeefficientlytheembeddingmethod.

2019/10/11 GraphRepresentationLearning 11

Page 12: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

HierarchicalPreservingNetworkEmbedding

q PairwiseProximityPreservation

2019/10/11 GraphRepresentationLearning 12

Page 13: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

HierarchicalPreservingNetworkEmbedding

q HierarchicalStructurePreservation§ Horizontalrelationship:

§ Verticalrelationship:

𝒄𝒗𝒍𝒄𝒖𝒍 𝒄𝒘𝒍𝒄(𝒍)𝟏

𝒄𝒋𝒍

𝒄𝒌𝒍-𝟏

2019/10/11 GraphRepresentationLearning 13

Page 14: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

GalaxyNetworkEmbedding

q Objective

2019/10/11 GraphRepresentationLearning 14

Page 15: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Proof

q PairwiseProximityPreservation

q HierarchicalStructurePreservation

§ Horizontal relationship:

§ Vertical relationship:

HierarchicalPreservingNetworkEmbedding

GalaxyNetworkEmbedding

?=>

2019/10/11 GraphRepresentationLearning 15

Page 16: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Proof

Lemma1

ThecommunityrepresentationslearnedfromrecursivelyoptimizingtheobjectiveEq.(5)with

thestrategyEq.(6)preservetheconstraintsEq.(3)andEq.(4).

⟹Vertical relationship:

Horizontal relationship:

2019/10/11 GraphRepresentationLearning 16

Page 17: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

p Facebook social network datasets:

p Amherst Collegep Hamilton Universityp Georgetown University

p Hierarchical random graphs (HRG):

p syn_with_125nodesp syn_with_1800nodesp syn_with_2560nodesp syn_with_3750nodes

2019/10/11 Graph Representation Learning 17

Dataset Baselines

p Spectral Clustering [Tang and Liu, 2011]

p DeepWalk [Perozzi et al, 2014]

p Node2vec [Grover and Leskovec, 2016]

p LINE [Tang et al., 2017]

p GraRep [Cao et al., 2015]

p MNMF [Wang et al., 2017]

Page 18: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

2019/10/11 Graph Representation Learning 18

Hierarchical Community Detection

Page 19: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

2019/10/11 Graph Representation Learning 19

Network Visualization

Page 20: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

2019/10/11 Graph Representation Learning 20

Vertex Classification

Page 21: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

HierarchicalCommunityStructurePreservingNetworkEmbedding:ASubspaceApproach

𝐋𝐮𝐧𝐃𝐮∗,𝑄𝑖𝑛𝑔𝑞𝑖𝑛𝑔𝐿𝑜𝑛𝑔∗,Y𝑖𝑚𝑖𝑛𝑔𝑊𝑎𝑛𝑔∗,𝐺𝑢𝑜𝑗𝑖𝑒𝑆𝑜𝑛𝑔∱ ,𝑌𝑖𝐿𝑢𝑛𝑗𝑖𝑛,𝑊𝑒𝑖𝐿𝑖𝑛.HierarchicalCommunityStructurePreservingNetworkEmbedding:ASubspaceApproach.AcceptedbyCIKM,2019.

2019/10/11 GraphRepresentationLearning 21

Page 22: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

DrawbacksofGNE

q Failedwhenembeddingdeepercommunities§ Radiishrinkexponentially

§ Datasparsityinadeepercommunity

q Probablyovervaluedhierarchicalinformation§ Verticesacrosscommunityareexponentially

distantthanthosewithinthesamecommunity.

2019/10/11 GraphRepresentationLearning 22

Page 23: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

HowtoRepresent?

q Subspace§ Naturalhierarchicalstructure

§ Deepercommunitycorrespondingtolowerdimensionalsubspace

2019/10/11 GraphRepresentationLearning 23

Page 24: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

HowtoLearn?

q Formulatingtheproblemintoanoptimizationproblemwithsubspaceconstraints§ Modelingcommunityaffiliationbysubspace

§ Reducingtherepresentationdimbyconstrainingtherankofbasevectors

q Designingefficientlearningalgorithm§ Fromglobaltolayer-wiseoptimization

§ Fromdiscretetodifferentiableoptimization

2019/10/11 GraphRepresentationLearning 24

Page 25: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

HierarchicalStructurePreserved

q PreservationofStructurewithinIndividualCommunities

q PreservationofStructureamongCommunities

q LowRankConstraints

2019/10/11 GraphRepresentationLearning 25

ℒJ = K log𝜎(||𝑢RS − 𝑢U

S ||) + 𝑘 ⋅ 𝔼[\~ \̂[log𝜎(−||𝑢`S − 𝑢U

S ||)]U ,R ∈c

Where,𝑢U(d) = 𝑆efg 𝑢U

(d-J) for𝑙 = 1…𝐿, 𝑣U ∈ 𝑉

ℒm =KK K ΔURd − ΓURm

|pg|

RqU)J

pg

UqJ

r

dqS

ℒs = KK𝑟𝑎𝑛𝑘(𝑆Ud)pg

UqJ

r

dqS

Page 26: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

2019/10/11 Graph Representation Learning 26

Vertex Classification

Page 27: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

2019/10/11 Graph Representation Learning 27

Link Prediction

Page 28: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

2019/10/11 Graph Representation Learning 28

Network Visualization

Page 29: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Outline

q HierarchicalInfocanbeobservedtoacertainextentinonlinenetworks.

2019/10/11 GraphRepresentationLearning 29

Explicit hierarchy with attributes Implicit hierarchy with tags

#

#University

#Major

#EnrollmentYear

TwitterNetworkFacebook Network

Page 30: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Tag2Gauss:LearningTagRepresentationsviaGaussianDistributioninTaggedNetworks

LunD𝐮∗,YunWan𝑔∗,GuojieSon𝑔∱ ,XiaoMa,LichenJin,WeiLin,FeiSun.Tag2Gauss: LearningTagRepresentationsviaGaussianDistributioninTaggedNetworks.InProceedingsofIJCAI,2019.

2019/10/11 GraphRepresentationLearning 30

Page 31: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

HowtoRepresent?

q Representtagsandnodessimultaneouslyq Tagsrepresentnodecommunitieswithintricateoverlappingrelationships

q Distribution:Tag;Samplefromdistributions:Node

2019/10/11 GraphRepresentationLearning 31

Page 32: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Howtolearn?

2019/10/11 GraphRepresentationLearning 32

q Tag2Gauss Framework:

§ Tag-view Embedding § Node-view Embedding § Multi-task Learning

Tag View Embedding Module Node View Embedding Module

Max­Margin Ranking Objective NCE Objective+=Objective

...

Forward  

Backward

GCN

...

NodeTag

Multi­Task Learning 

...

Tag Relation Sequence

ProjectHybrid  

Walker

Tag Distribution 

 

Sample 

...

Page 33: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiments

q Datasets:§ Leetcode (652nodes,1096edges,34tags,3labels)§ Bilibili (11727nodes,187148edges,151tags,10labels)§ Cora.(2707nodes,5429edges,1433tags,7labels)

q Baselines§ DeepWalk (KDD’14)§ Node2vec(KDD’16)§ HybridDeepwalk (NaiveDesign)§ GraphSage (NIPS’17)

2019/10/11 GraphRepresentationLearning 33

Page 34: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

2019/10/11 Graph Representation Learning 34

The Advantage of Distribution Representations

Segment Tree

ArrayLinked List

DFS

Topological SortDivide and Conquer

Rejection SamplingQueue

TrieDP

Binary Indexed TreeTwo Pointers

Tree RecursionHeap

Sort

BinarySearch

Bit Manipulation

Greedy

Backtracking

BSTMinimax

Brainteaser

Segment TreeArray

Linked List DFS

Topological Sort

Divide and ConquerRejection Sampling

TrieDP

Binary Indexed TreeTwo Pointers

Recursion

Bit Manipulation

BSTBacktracking

Sort

BinarySearch

Minimax

Brainteaser

Greedy

HeapQueue

Tree

Page 35: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

2019/10/11 Graph Representation Learning 35

Node Classification

Page 36: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

MainContents

q Background

q Graphembeddingwithhierarchicalcommunitystructure

q Domainadaptivegraphembedding

q Futureworks

2019/10/11 GraphRepresentationLearning 36

Page 37: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

DANE:DomainAdaptiveNetworkEmbedding

YizhouZhang, GuojieSon𝑔∱ ,LunDu,Shuwen Yang,Yilun Jin.DANE:DomainAdaptiveNetworkEmbedding.InProceedings ofIJCAI,2019.

2019/10/11 GraphRepresentationLearning 37

Page 38: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Motivation

q Domainadaptation§ Transferringmachinelearningmodelsacrossdifferentdatasetsto

handlethesametaskq Domainadaptationonnetworksissignificant:

§ Reducethecostoftrainingdownstreammachinelearningmodelsbyenablingmodelstobereusedonothernetworks

§ Handlethescarcityoflabeleddatabytransferringmodelstrainedwellonalabelednetworktounlabelednetworks

q Itisimportanttodesignanetworkembeddingalgorithmthatcansupportdomainadaptation.

2019/10/11 GraphRepresentationLearning 38

Page 39: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Challenges

q Embeddingspacealignment§ Structurallysimilarnodesshouldhavesimilarrepresentationsintheembeddingspace,eveniftheyarefromdifferentnetworks.

q Distributionalignment§ Embeddingvectorsofdifferentnetworksshouldhavesimilardistributioninembeddingspace.

§ Mostmachinelearningmodelsperformasguaranteedonlywhentheyworkondatawithsimilardistributionastheirtrainingdata.

2019/10/11 GraphRepresentationLearning 39

Page 40: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

TechniqueFramework:Overall

2019/10/11 GraphRepresentationLearning 40

Page 41: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

AdversarialLearningRegularization

q Discriminatortoavoidtheinstabilityofadversariallearning:

q Adversarialtraininglossfunctiontoconfusethediscriminatoris:

qOveralllossfunction

2019/10/11 GraphRepresentationLearning 41

Page 42: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

2019/10/11 Graph Representation Learning 42

Comparison with Baselines

Page 43: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Experiment

2019/10/11 Graph Representation Learning 43

Comparison with the Variant without adversarial learning

Page 44: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

MainContents

q Background

q Graphembeddingwithhierarchicalcommunitystructure

q Domainadaptivegraphembedding

q Futureworks

2019/10/11 GraphRepresentationLearning 44

Page 45: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

FutureWorks

q Understandingofgraphneuralnetworks§ Whydoesitwork?

§ Whatkindofgraphisitmoreeffective?

q CustomizedGNNfordifferentkindsofgraphsq Applications

§ Semi-structureddatamining

§ Sourcecodeanalytics

2019/10/11 GraphRepresentationLearning 45

Page 46: Graph Representation Learning with Hierarchical Structure ... · Experiment p Facebook social network datasets: p Amherst College p Hamilton University p Georgetown University p Hierarchical

Q&A

2019/10/11 GraphRepresentationLearning 46

Welcome to collaboration or internship!

[email protected]