how do newcomers blend into a group?: study on a social network game

CyberAgent,Inc.

HowDoNewcomersBlendintoaGroup?:StudyonaSocialNetworkGame

CyberAgent.Inc,TechnicalDept.AkihabaraLaboratory M.Takano,K.Wada,andI.Fukuda

15/12/06 1

DOCMAS&WEIN2015Workshop@WI-IAT

CyberAgent,Inc.

CooperaTveBehavior

Coopera'vebehaviorrequiresactors'costs,butgivebenefitstorecipients.Importantfactorsforhumansociety.BigQues'oninEvolu'on.15/12/06 2

CyberAgent,Inc.

ProblemofCooperaTon

MutualcooperaTonincreasesourbenefit.WhyisitsevoluTonthequesTon?

315/12/06

CooperaTngeachother

ThebothgetbenefitsCooperate

Cooperate

CyberAgent,Inc.

ProblemofCooperaTon

MutualcooperaTonincreasesourbenefit.WhyisthisevoluTonthequesTon?

415/12/06

Butifonedefects

Thedefectorgetshigherbenefitthananother(cooperator).

Defect

Cooperate

CyberAgent,Inc.

ProblemofCooperaTonMutualcooperaTonmakebenefitforall.

ButunilateraldefecTonmakemorebenefitstodefectors.→Coopera'vepopula'onwillbecomedefec'vepopula'on

515/12/06

HighBenefit

LowBenefit

GoodrelaTonship,butunstable.

Stable,butbadrelaTonship

CyberAgent,Inc.

ProblemofCooperaTon

However,humanscooperateeachother

Humanshouldhavego\encoopera'onmechanismsduringtheevoluTonary process

15/12/06 6

CyberAgent,Inc.

MechanismsofCooperaTon

ü KinSelecTonü DirectReciprocityü IndirectReciprocityü SpaTalSelecTonü MulT-levelSelecTon

ref.DavidGRand,etal.,HumancooperaTon.TrendsincogniTvesciences,Vol.17,No.8,pp.413-25,2013.

ThesemechanismsgenerateassortmentsbetweencooperatorsanddefectorstokeepinteracTonamongcooperatorsbyexcludingstrangers.i.e.,cooperaTonmechanismsexcludestrangersfromcooperaTvegroups.

715/12/06

CyberAgent,Inc.

ProblemofCooperaTonMechanismsü  KinSelecTonü  DirectReciprocityü  IndirectReciprocityü  SpaTalSelecTonü  MulT-levelSelecTon

Thereciprocalmechanismsrequirecoopera'veinterac'oninfirst'memee'ng,becausereciprocalcooperatorscooperateothersasthereacTonoftheircooperaTontoavoidtocooperatedefectors.ü  i.e.,toincreasereciprocalrelaTonships,infirstTmemeeTng,theyshould

cooperate(notexclude)strangerstoconstructgoodrelaTonships.

Thereareinterac'onrisks,becausetheyareunfamiliareachother.

→Howdohumansconstructreciprocalrela'onshipswithstrangers?

815/12/06

CyberAgent,Inc.

OurApproach

Weapproachedthisproblembasedondataanalysisofasocialnetworkgame.SocialNetworkGame(SNG):ü OnetypeoftheOnlineGames.ü Alotofplayers,andtheirallbehaviorwasstoredaslogdata.

ü Playerscooperateandcompeteeachother.→Wecanobservetheirsocialbehaviorindetail.

915/12/06

CyberAgent,Inc.

PreviousStudiesandOurApproach

1015/12/06

ParTalandBiasedDataHardtoUnderstand

CleanandDetailedDataEasytoUnderstand

MathemaTcalModelSimulaTon

ExperimentsinLab

✊ ✋

Data Analysis of SNGsObservaTon

Study

Thedataanalysisofthegamedatacatchupotherapproaches.ü WecanobservedetailbehaviordataofmassiveplayerslikemathemaTcalmodelsandsimulaTons.

ü ThedataismoredetailthanobservaTonstudies.

ü Thegameenvironmentismoreopen-endedthanothers.

CyberAgent,Inc.

SocialNetworkGame

1115/12/06

•  URL:h\p://vcard.ameba.jp•  Lang:Japanese•  Since2012/10Weanalyzedthisgamedatafor2weeks(2013/03/25to2013/04/08).

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TheMinimumSetofGameRules

15/12/06 12

•  Playersaimtogetpointsandtorisearankingbasedonthepoints•  Eachplayerbelongedtoagroup（Thegroupsize:1〜50players）

•  Thegamesystemsupportjointworksingroups.•  Playersgetadvantageswhentheydojointworkwiththeirgroup

members•  AplayercanmigratefromagrouptoanothergroupatanyTme.

•  Playerscommunicatebysendingsimplemessage(30Japanesecharacters). •  Messaging:no-costandnon-beneficialbehavior.

→Weanalyzed2typessocialinteracTon:cooperaTonandmessaging

1:Smith（12040pt）

2:MarTn（11010pt）

3:Anderson（11005pt）

4:Ken（9015pt）

・・・

Migra'on

Ranking

Simplemessaging

Coopera'on

CyberAgent,Inc.

CooperaTveBehavior

ü WefocusonaspecificgamesituaTonlikeLeadergameü IntheSNG,playersbehavevariously.ü WecannottrackallcooperaTvebehavior.→Weregarded

Aplayer'sthiscooperaTonfrequencyintheSNG ≒theplayer'scooperaTveness

ü PayoffMatrixofthesituaTonlikeLeadergame

1315/12/06

Cooperate Defect

Cooperate -,- 1,3

Defect 3,1 0,0

Cooperatorget1point.Defectorget3point.

CyberAgent,Inc.

InteracTonofFirstTimeMeeTngü WetrytoobservetheconstrucTonprocessofreciprocalrelaTonships.ü InthisSNG,playersconstructedtherelaTonships.

ü ref:MasanoriTakano,KazuyaWada,andIchiroFukuda,"ReciprocalAltruism-basedCooperaToninaSocialNetworkGame",NewGeneraTonCompuTng(inpress).h\p://arxiv.org/abs/1510.06197

ü Weobservedplayers'behaviorattheamermigraTonü Didthenewcomersandgroupmemberscooperateeachother?

ü HowwasthedifferenceinsocialinteracTonbetweenthenewcomersandthegroupmembers?

1415/12/06

Migra'on

CyberAgent,Inc.

AnalysisandResults

15/12/06 15

DOCMAS&WEIN2015Workshop@WI-IAT

CyberAgent,Inc.

TwoRegressionModels

ü AModelforCoopera'ontoothersü WerenewcomerscooperaTve?ü Howwascoopera'ontoothersinfluencedbyrecipients'behavior?

ü AModelforCoopera'onfromothersü Werenewcomerscooperated?ü Howwascoopera'onfromothersinfluencedbyactors'behavior?

1615/12/06

CyberAgent,Inc.

NegaTveBinomialRegressionModel(GLM)

1715/12/06

AModelforCooperaTontoOthersü Thismodelisintendedtoexplainthenumberofcoopera'onbyplayers'experiencesandaVributes

ResponseVariable:NumberofCooperaTontoOthers

ExplanatoryVariables:ExperiencesandA\ributes

SampleSize:400,000

CyberAgent,Inc.


1815/12/06

AModelforCooperaTontoOthersü Didnewcomerscooperate?

f:NewcomerFlag(0or1)•  f=1:Newcomer(firstdayofmigraTon)•  f=0:ExisTngGroupMembers

Ifβ4>0thenitshowsthatnewcomersmoreomen cooperatethanexis'nggroupmembers.


CyberAgent,Inc.


1915/12/06

AModelforCooperaTontoOthersü Howdidnewcomersreactotherscoopera'on?

C'(1-f):(Exis'ngGroupMember's)NumberofCooperaTonfromOthers

Ifβ6>β5>0thenitshowsnewcomerswereinfluencedbycooperaTonfromothersmorethanexis'nggroupmembers.

C'f:(Newcomer's)NumberofCooperaTonfromOthers


CyberAgent,Inc.


2015/12/06

AModelforCooperaTontoOthersü Howdidnewcomersreactothersmessaging?

g'(1-f):(Exis'ngGroupMember's)NumberofMessagingfromOthers

Ifβ8>β7>0thenitshowsnewcomerswereinfluencedbymessagingfromothersmorethanexis'nggroupmembers.

g'f:(Newcomer's)NumberofMessagingfromOthers


CyberAgent,Inc.


2115/12/06

AModelforCooperaTontoOthersü Theotherswereenteredascovariatestocontrolfortheothereffects.

TheothersarecovariatesResponseVariable:NumberofCooperaTontoOthers

CyberAgent,Inc.

Results–ModelforCooperaTontoOthers

•  NewcomerstendedtocooperateotherswithoutotherscooperaTonandmessaging.

•  Newcomersomencooperatedgroupmembers.ü β4>0

•  Incomparisonbetweennewcomersandgroupmembersü Newcomersdidn'ttendtobeinfluencedbyotherssocialbehavior.ü β5>β6>0,β7>β8>0

2215/12/06

β4β5β6β7β8

CyberAgent,Inc.


2315/12/06

AModelforCooperaTonfromothersü Thismodelisintendedthenumberofcoopera'onfromothersbybehaviorandaVributes

ResponseVariable:NumberofCooperaTonfromOthers

ExplanatoryVariables:BehaviorsandA\ributes

SampleSize:400,000

CyberAgent,Inc.



2415/12/06

AModelforCooperaTonfromothersü Werenewcomerscooperated?

f:NewcomerFlag(0or1)•  f=1:Newcomer(firstdayofmigraTon)•  f=0:ExisTngGroupMembers

Ifβ4>0thenitshowsthatnewcomersweremoreomencooperatedthanexis'nggroupmembers.

CyberAgent,Inc.


2515/12/06

AModelforCooperaTonfromothersü Howdidnewcomersreactotherscoopera'on?

C(1-f):(Exis'ngGroupMember's)NumberofCooperaTontoOthers

Ifβ6>β5>0thenitshowsPlayersweremoresensiTvenewcomers'cooperaTonthanexis'ngmembers'cooperaTon.

Cf:(Newcomer's)NumberofCooperaTontoOthers


CyberAgent,Inc.


2615/12/06

AModelforCooperaTonfromothersü Howdidnewcomersreactothersmessaging?

g(1-f):(Exis'ngGroupMember's)NumberofMessagingtoOthers

Ifβ8>β7>0then itshowsPlayersweremoresensiTvenewcomers'messagingthanexis'ngmembers'messaging.

gf:(Newcomer's)NumberofMessagingtoOthers


CyberAgent,Inc.


2715/12/06

AModelforCooperaTonfromothersü Theotherswereenteredascovariatestocontrolfortheotherfactors.

Theothersarecovariates


CyberAgent,Inc.

Results–ModelforCooperaTonfromOthers

ü Newcomerstendedtobecooperated,newcomersmessagingisimportanttogetcooperaTon.

ü  Newcomerswereomencooperatedbygroupmembers.ü  β4>0

ü  PlayerswerelesssensiTvetonewcomers'cooperaTonthanexis'nggroupmembers'cooperaTon.ü  β5>β6>0

ü  PlayersweremoresensiTvetonewcomers'messagesthanexis'nggroupmembers'messages.ü  β8>β7>0

2815/12/06

β4β5β6β7β8

CyberAgent,Inc.

Summary

ü TheSNGplayersresolvedinteracTonriskinfirstTmemeeTng.ü Infirst'memee'ng,theyo]encooperatedeachother.

→TheymayhaveconstructedreciprocalrelaTonships.

ü ref.ReciprocalrelaTonshipsinthisSNG.ü MasanoriTakano,KazuyaWada,andIchiroFukuda,"ReciprocalAltruism-basedCooperaToninaSocialNetworkGame",NewGeneraTonCompuTng(inpress).h\p://arxiv.org/abs/1510.06197

2915/12/06

CyberAgent,Inc.

Summary

ü Thedifferencebetweennewcomersandexis'nggroupmembersinmessagingü PlayersweremoresensiTvenewcomers'messagingthanexis'ngmembers'messaging.

ü Messagingisnotrisky

ü Messaging:no-costandnon-beneficialbehaviorü IntheriskysituaTon(firstTmemeeTng),playersmayhaveusenon-riskyinteracTontoconstructreciprocalcooperaTon.

3015/12/06

CyberAgent,Inc.

Appendix

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CyberAgent,Inc.

GameRule–RaidBa\le

15/12/06 32

①Search Enemies

Player

⑤Theirpointgainincreaseby1.5Tmes

⑥Ranking

GroupMembers

②FindanEnemy　→Ba\leStart

③CallforHelp

④A\ack

1:Smith（12040pt）

2:MarTn（11010pt）

3:Anderson（11005pt）

4:Ken（9015pt）

・・・

Playersba\lewithenemiestogeteventpointfortheranking

•  PlayersacquireEventPointinproporTontotheirpower.•  Thenumberofa\ackisfinite.→Playershavetoeffec'velygetthepointsfortheranking.

CyberAgent,Inc.

TestScenario

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A\ack WaitA\ack - 1,3Wait 3,1 0,0

Tosimplifythis,considerthattwoplayersba\ledtheenemy

Aplayerwaitanother'sa\acktouseeffecTvelytheirresource.

WeregardedtheAVackbehaviorascoopera'on.

Whentheenemy'shitpointsareveryfew

A\ack

HP

Playersacquiresmallerpointswhen"A\ackpower>Enemy'sHP"thanwhen"A\ackpower≦Enemy'sHP"

CyberAgent,Inc.

AssortmentCooperatorsandDefectors

Densitydistribu'onofthepropor'onofcooperatorsineachgroup.

3415/12/06

0.0

0.1

0.2

0.3

0.00 0.25 0.50 0.75 1.00Proportion of Cooperators

Dens

ity

MasanoriTakano,KazuyaWada,andIchiroFukuda,"EnvironmentallyDrivenMigraToninaSocialNetworkGame",ScienTficReports,5,12481;doi:10.1038/srep12481(2015).

how do newcomers blend into a group?: study on a social network game

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