Consistent Communication with Control

Consistent Communication with Control

Jan M. Allbeck and Norman I. Badler Center for Human Modeling and Simulation

University of Pennsylvania

200 S. 33rd St., Philadelphia, PA 19104-6389 allbeck@graphics.cis.upenn.edu

ABSTRACT

Weare seekingto outline aframeworktocreateembodied

agentswithconsistencybothintermsofhumanactionsand

communications ingeneral and individual humans in par-

ticular. Ourgoal is to drive this consistent behavior from

internalorcognitivemodelsoftheagents.First,wedescribe

channels ofnon-verbalcommunicationandrelatedresearch

inembodiedagents. We thendescribe cognitive processes

thatcanbeusedtocoordinatethesechannelsofcommuni-

cationandcreateconsistentbehavior.

1. INTRODUCTION

Consciouslyor not, peoplespendtheir entirelivesobserv-

ingother people. Wehaveunconsciousandculturalnorms

ofhumanbehaviorand aremorelikelytonotice theunex-

pectedratherthanthenaturalorexpected. Intheembodied

agentresearchcommunity,agentbehaviorscreatedwithan

attempttoconformtoournominalexpectationsaretermed

believable. Unfortunately, this termis awkward to dene.

Believable means \to accept as real." But real is itself a

loaded term, as thereare numerousaspects of realpeople

that embodied agents donot or cannot portray. Usually,

itisthecharacter'sactionsandcommunicationsthatought

to appear similar enough to those of real people that we

accepttheanimationashavingbelievablethoughtsoremo-

tions. Iftheseconditionsaresatised weare capableofig-

noringsignicant non-humanvariantsinform,appearance,

orstructure. Oneonlyneedlook atthewiderangeofani-

matedcartooncharactersthatcommunicatetheirpresumed

thoughtsandfeelingstoseethatrealityinexpressionisthe

strongerdeterminerofbelievability[29].

Ifactionsandcommunicationsarethetriggersforourunder-

standing ofanimatedcharacters, thenthesemustbe man-

ifest on the character in human-like ways. For example,

mechanicalspeechmaydestroythebelievabilityofanother-

wiseaccuratelyrenderedcharacter(unlessweneedtobelieve

that it is arobot!); an awkward mechanical walkcan dis-

tractusfromseeingwell-executedandsubtlefacialexpres-

sions. Hereinliesthe rstmajor goal of thisstudy. What

weareseekingisananimatedembodiedagentwithconsis-

tency both interms of our expectations of human actions

andcommunications ingeneralandourexpectationsofin-

dividualhumansinparticular. Theagent'sbehavior must

be consistent frommoment tomoment andfrom situation

tosituation. Thereshouldbenowildmoodswingsorcom-

plete loss offocus. Departuresfrom consistency might be

interpreted as dramatic eects or, more likely, as internal

conictswithintheagent'sowncognitivestate 1

. Normally,

weshouldexpectthecognitivestateoftheagenttobecon-

sistentwitheverylevelofitsbehavior: theexpressiononits

face,theaectofitsmovements,theactionsitperforms,and

thegoals whichitpursues. Also, cognitivestate(andthus

actions)mustbeconsistentwiththecontextorsituationin

whichtheagentndsitself.

Inconsistencies atany levelcan causemixedmessages and

miscommunication. AsBurgoonetal[6] indicates,\When

enactingmultichannelnonverbalpresentations,commonsense

saysthat oneshouldcoordinatethe channels to producea

consistent message." Sometimesmixedmessagesaredelib-

erateasinthecaseofjokesandsarcasm. Othertimes,mixed

messagesareindicativeofinternalconfusion[6]. Theremay,

of course, be times when internal confusion is our intent,

butitseemsmoreprudenttorstmodelunconfusedinter-

nal states and demonstrate consistent communication. If

thetheoryworks,weshouldbeabletoportrayinconsistent

behaviorsandhaveobserversinferconictedorunbelievable

stateswithintheagent.

Our secondmajor goal is to drivethis consistent behavior

frominternalor cognitive modelsofthe agent. It issome-

whatsurprisingthatagentmodelershavebeensoheavilyin-

uencedbyEkmanandFriesen[11]that manyconcentrate

onlyonthebasicfacialexpressionsofhappy,sad,anger,fear,

anddisgustanddonotincludeinternalreectivestatessuch

asdetermination, confusion,vacillation,andanxiety. Simi-

larly,humangestureperformanceappearstoreectinternal

agent stateinsubtlebutobservableways[2]. Onlybyrep-

resentingthe agent'sinternal cognitive state and thus the

information, beliefs, desires, and intentions that motivate

it,canweachieveconsistentexternalizedactions.

In this paper, we will concentrate onnonverbalcommuni-

1

Inthispaperweabusetheterm\cognitive." Bycognitive

stateorprocess,wealsoincludeotherinternal,mentalpro-

Wewill propose aparameterized agent modelthat creates

consistent behaviors and allows controllability at dierent

levels. Wewill describe theimportance and interactionof

thecomponentsand theirmanifestationinthe channels of

nonverbalcommunication.

2. MANIFESTATIONS OF NONVERBAL COMMUNICATION

Though verbal communication is the standard channel of

communication used by people, nonverbal communication

alsocontainsvaluableinformation. Infact,theinformation

containedinnonverbal communicationmay be more valu-

ableinsomesituations. InSnowCrash[28]NealStephenson

describesaninternationalbusinessmeetingtakingplacein

avirtualworld:

They comehere [TheBlack Sun]totalk turkey

withsuitsfromaroundtheworld,andtheycon-

sideritjustasgoodasaface-to-face. Theymore

orlessignorewhatisbeingsaid{alotgetslostin

thetranslation, afterall. Theypay attentionto

the facialexpressions andbodylanguageofthe

peopletheyaretalkingto. Andthat'showthey

knowwhat'sgoingoninsideaperson'shead{by

condensingfactfromthevaporofnuance.

Theinternalorcognitivestateofapersoncanmanifestitself

inallofthechannelsofnonverbalcommunication. Accord-

ingto[19]thechannelsofnonverbalcommunicationare:

facialexpressions(smiles,nods)

gestures (especiallyhandandarmmovements)

bodymovements

posture

visualorientation(especiallyeyecontact)

physicalcontacts(handshakes,patting)

spatialbehavior(proximity,distance,positions)

appearance(includingclothes)

non-verbalvocalizations

We will briey describe each of these channels and some

oftheresearchthat hasbeendoneintheembodiedagents

community.

2.1 Facial Expressions

Facialexpressionsareknowntoexpressemotion[11],butfa-

cialexpressioncanindicatewhatapersonisthinkingaswell

asfeeling. Thefacereectsinterpersonalattitudes,provides

nonverbalfeedback onthe commentsofothers, opens and

closeschannelsofcommunication,complementsorqualies

waysofgeneratingfacialexpressionsforspeech.Brandgen-

erates facialanimationfrominformationinanaudiotrack.

Poggi and Pelachaud concentrate on the visual display of

intentionsthroughfacialanimationbasedonsemanticdata.

They modelperformatives, which are the type ofaction a

sentenceperforms, such as requesting or informing. They

alsodiscusshowthedegreeofcertainty,thepowerrelation-

ship, the type of social encounter, and the aective state

eectthefacial animation.

Cassell etal[7] present asystem whichautomatically gen-

eratesandanimatesconversationsbetweenmultipleagents.

A dialogue plannercreates theconversationand generates

andsynchronizesappropriatefacialexpressions,intonation,

eyegaze,headmotion,andarmgestures.

2.2 Gestures and Body Movements

Gestures are voluntaryor involuntarymovementsthatare

intended to communicate. They may involve any part of

thebody. Theyareusedtoemphasize,clarify,oramplifya

verbalmessage. Theycanalsoregulateorcontrolahuman

interaction, ordisplayaect[19].

By contrast body movements are not intended to convey

information. Body movementsinclude, walking, reaching,

turning, bending, etc. The mannerinwhichthese actions

are done can help convey the cognitive state of the per-

former. Peoplecanwalkindramaticallydierentways:fast,

slow,straight,swerved,proudly,sadly,joyfully,etc.[25].

Gesturalcommunicationandbodylanguagehavebeenstud-

iedbyseveralgroupse.g.,MorawetzandCalvert[21], Kur-

landeretal[18]. TheEMOTEtoolofChietal[9] controls

the expressive shape and eort characteristics of gestures.

Amaya etal [1] studied the expression of emotion on the

body.

2.3 Postures

Posture is an indicator of the degree of involvement, the

degreeofstatusrelativetotheotherparticipants,orthede-

gree oflikingfor theotherinteractants. A forwardleaning

posture,forexample,canindicatehigherinvolvement,more

liking,andlowerstatusinsituationswheretheparticipants

donotknoweachotherverywell. Postureisalsoakeyindi-

catoroftheintensityofsomeemotionalstates. Adrooping

postureisassociatedwithsadnessandarigid,tenseposture

isassociatedwithanger. Theextendtowhichthecommuni-

catorsreecteachother'sposturemayalsobeanindication

ofrapportoranattempttobuildrapport[17].

Becheiraz and Thalmann[3] present amodelof nonverbal

communicationwhereagentsreactto oneanotherinavir-

tualenvironmentbasedontheirpostures. Relationshipsbe-

tweentheagentsevolvebasedontheperceptionsofpostures.

2.4 Visual Orientation

What apersonpaysattention toand howmuchattention

theypay isanotherchannelofcommunication. Aperson's

gaze andeventhe dilation andconstrictionor their pupils

Johnson and Rickel [15] present an animated pedagogical

agent,whichusesbothgesturesandattentiontoaidinthe

instruction of manual tasks. Cassell et. al [7] created an

interfaceforchatroomavatarsthatallows theuserto give

conversationalcuesthroughattentioncontrol. Ifausersees

anagent thatheis talkingto begin tolook away fromhis

avatar moreand more,thenthis is probablyanindication

thattheagentnolongerwantstoparticipateintheconver-

sation.

2.5 Physical Contacts and Spatial Behavior

Physicalcontactsmaybeself-focusedorother-focused. Self-

focused touching may reect a person's cognitive state or

ahabitand includenervous mannerisms. Thereare many

kindsofother-focusedtouching,including,irritating,conde-

scending,comforting,andelectric. Themeaningofatouch

behaviorisoftenderivedmorefromitscontextandmanner

thanfromitsconguration.

Spatialbehaviorreferstosocialandpersonalspace. Spatial

behaviorcanvarybasedonmanyaspectsofindividualsin-

cluding,age,gender,status,roles, culture,personality and

context. Studiesshowthatconversationaldistanceisrelated

togeneralcomfortlevel[6].

Physical contactsandspatialbehaviorsare typesofbehav-

iors that animation artists do well, but embodied agents

researchersdo not focus on. Inorderto create consistent

communication these two channels of communication will

havetobecoordinatedwiththeotherchannels.

2.6 Appearance

Amongother things, appearance can provide information

about,behavior,valuesandattitudes,andoccupation. An

immaculateappearancecanindicatethatapersonpaysat-

tentionto details. Wearing hikingbootscanindicatethat

thepersonlikestheoutdoors. Anold-fashionedappearance

sometimesindicatesold-fashionedvalues,andexcessivejew-

elrycanindicatematerialism. Wearingattire thatis func-

tionalandprotectivecanindicateabluecollarjob,whereas

whitecollarworkerswearmoreformalclothing[19].

There are many companies and research laboratories, in-

cludingBlaxxunInteractive[4]andMIRALab[20],working

onmodelingvirtualhumanbodies,skin,hair,andclothing.

2.7 Nonverbal vocalizations

Nonverbalvocalizationsarevocalsoundsotherthanwords.

Thisincludestoneofvoicewhichisknowntoconveyemo-

tionalinformation[17]. Forexample,depressedpeoplespeak

inalow,slowvoice,withfallingpitch.

The Sims [27] is a good example of the use of nonverbal

vocalizations inembodied agents. In this game, the char-

acterslivetheirdailylivesincluding,participatinginpolite

conversationsandangrydiscussions,butthecharactershave

nodiscerniblespokenlanguage. Thegame'scharacterscom-

municatethroughgestures,thought-bubbles,andnonverbal

vocalizations. Inthegame,itiseasytodistinguishapolite

conversationfrom anheated argumentby thevolume and

3. AGENT COGNITIVE MODEL

Inordertocreateanagentwhosecognitivestateisreected

inthesechannelsofcommunicationandthereforecreatecon-

sistent communication and behavior, we need to examine

whatcognitive processeseectthechannelsofcommunica-

tion. Booksconcerningnonverbalcommunication[17,19,6]

often talk about the eects of thefollowing cognitive pro-

cessesoncommunication: age,status,gender,culture,role,

context,emotion,mood,andpersonality.

3.1 Age and Status

Inanyinterpersonalsituation,oneperson'sstatusisalways

atleastalittleaboveorbelowtheotherperson's[16], and

ageis oftenacomponentofstatus. Age andstatusare re-

ectedinmanydierentcommunicationchannels. Inorder

topresent consistentagent behavior,thesechannels should

allindicatethesameageandstatuscognitivestates.

Forexample,gestureschangeandbecomemoresubtlewith

age [19], and peopleof higher status seem to gesture less

frequently[19].Interpersonaldistancealsochangeswithage.

Distance seems to increase with age, but is always closer

withpeersthanwiththosethatareyoungerorolder. Older

people are more likely to touch younger people thanvice

versa[6],whichisprobablyafactorofbothstatusandage.

Peopleofmoredominancearemorelikelytoengage inun-

wavering, direct looks. People tendto lower their eyes to

show deference to authority gures, and submission is of-

tenmarkedbyraisedeyebrows,whichconnotedeference[6].

Properposture signalsdominance. Highstatus peopleare

more condent and therefore comfortable in their space.

Nonverbalvocalizationsarealsoeectedbystatus. Ashort

\er"atthebeginningofasentenceisweak,butalong\er"

isstrong[17].

Theagentsresearchcommunityhas,tosomeextend,mod-

eledstatus. Hayes-Roth etal[12] haveexploredtheuse of

status withembodiedagentsintheform ofa master-slave

relationship. Theyillustratehowtheposturesandactionsof

thecharacterschangeastheservantbecomesthedominant

character. Poggi and Pelachaud [8] model status through

facial expressions calledperformatives,whichare facial ex-

pressionsthataccompanyandaddinterpersonalrelationship

information tospeech. Musse andThalmann [22]included

dominanceintheircrowdsimulations.

3.2 Gender

Physicalappearanceisanobviouschanneltocommunicate

gender,butgendershouldalsobeconsistentwiththeother

channels ofcommunications. For instance,pairs ofwomen

tend to engageinmore eye contactthan pairs ofmen[6].

Burgoon etal [6] alsodiscusses many othergender dier-

ences thateectthechannels ofnonverbalcommunication,

including: postures in which malestend havemore domi-

nant,lessaÆliative,andlessintimateposturesthanwoman,

andspatialbehaviorinwhichinsmallgroupsandinterper-

sonal interactions,women requirelesspersonalspace than

men.

Thoughbothmenandwomenhavebeenmodeledinvirtual

environments,wecurrentlyknowofnoimplementationthat

modelsgenderasacomponentofthecognitivestateofthe

3.3 Culture and Role

Itissaidthat culturalinformation isaminimumprerequi-

sitefor humaninteraction{in theabsence ofsuchinforma-

tioncommunicationbecomes atrialanderrorprocess[17].

Culturaldierencesincommunicationcanbeextensiveand

donotonlyincludethelanguagespoken.First,dierentcul-

tureshave dierentdistancesfor interacting. Insomecul-

turesstandingclose anddirectlyinfront ofapersonwhile

speaking is considered either anintimate or a hostile act.

Inother cultures, not standing close and directly facing a

person wouldbe considered rude. There are alsodierent

touchingbehaviors,gestures,andeyegazepatterns[17].

Itisalsowellknownthattherearesomesimilaritiesacross

cultures. Studieshaveshownthatthesixbasicfacialexpres-

sionscanbe distinguishedacross cultures[11]. Also,some

behaviorshavecross-culturalsimilarities,e.g.coyness,irt-

ing,embarrassment, open-handedgreetings, and alowered

posturefor showingsubmission[17].

Whilecultureisaveryimportantcomponentofhumanbe-

haviorandcommunication,ithasbeenneglectedasafocus

for the embodied agents researchcommunity,perhaps due

toitscomplexity.

Everycharacterinavirtualenvironmentshouldhavearole

thatitis playing,whetherit isaprofessor ofastrophysics,

atour guide,orjustamanwalking downthestreet. Roles

involve expectations, both fromthe individual playingthe

roleandfromthoseinteractingwiththeindividual playing

therole. Inorderfora character inavirtualenvironment

tobe consistent, itmustmeet theexpectationsof therole

itisplaying.

Rolesarelearned,generalizedguidelinesforbehavior. Among

otherthings,arole canstemfrom anindividual's occupa-

tion, kinship, age, sex, prestige, wealth, or associational

grouping. In a situation, one participant normally estab-

lisheshisorherroleandtheotherparticipant(s)musteither

goalong or counterwith adierent roledenition. There

mustbe an agreement onthe roles inorder to eectively

interact. Otherwise,communicationwillbreakdown[6].

Rolesinuencesmanyofthechannelsofnonverbalcommu-

nication. Takeforexampletherolesofdoctorandmechanic.

We have certain expectations about these roles. The ap-

pearance of adoctor is expected beclean and neat, while

amechanic may beverymessy. Wewouldalso expectthe

interpersonaldistance withadoctorto besmaller andthe

physicalcontactsmorefrequent(whencomfortingaswellas

examining). Confusionand alarmmight resultfromame-

chanicstanding tooclose ortouchingtoooften(eveniftry

tocomfortsomeoneaftershowingthemthebill).

IsbisterandHayes-Roth[13]haveexploredrolesinrelation

tointelligentinterfaceagents. Theyfoundthatmakingthe

roleofaninterfaceagentclearhelpstoconstraintheactions

userswilltakeintheircorrespondingroles.

3.4 Context

People all perceive situations dierently, and form dier-

entmentalrepresentationsoftheenvironment,people,and

predicatedontheirknowledgeandunderstandingofthesit-

uation. Anembodiedagent'sbehaviorshouldbeconsistent

withthecurrentcontext(oritsperceptionofit). Wewould

notexpectthesamebehaviorinanopera-houseasafootball

stadium.

TheproblemisthatcontextisadiÆcultthingtorepresent.

Notonlymustwetakeintoaccountallofthepeopleandob-

jectsintheenvironment,andtheembodiedagent'sfeelings

about them, and all of the action taking place inthe en-

vironment,andthefeelings abouttheactions,and feelings

about past events, and the overall feeling of the environ-

ment, butwemustthendecidewhatthe signicanceofall

ofthesefactorsare.

Althoughcontextisanimportantfeatureforagentsinvir-

tualenvironments,ithasnotbeenheavilyresearchedbythe

community. Itrequires attention,syntheticvision,arepre-

sentationof thesituation,and away todeterminewhat is

importantinthesituationbasedontheagent'scurrentcog-

nitivestate. Oncetheenvironmenthasbeenperceivedand

thesituationrepresented,thecontextcanbeusedtocreate

behaviorwhichiscontextuallyconsistent.

3.5 Emotion, Mood, and Personality

Emotionsandmoodeectmanyofthechannelsofnonverbal

communication. Theeectofemotionsonfacialexpressions

is well-knownandwell-studied[11], butotherchannelsare

eectedaswell. Lewis[19]indicatesthattensemoodscause

postures thatare rigidandupright,or slightlyleaningfor-

ward. Extremeinhibitiontendstocausewithdrawalmove-

ments and general motor unrest. Whendepressed, move-

mentsareslower,fewer,andhesitating. Bycontrast,elation

causesfast,expansive,emphatic,spontaneousmovements.

Theembodiedagentsresearchcommunityhasstudiedemo-

tion and mood more thanany of the other cognitive pro-

cesses [10, 8]. Personality isa patternof behavioral, tem-

peramental,emotional,andmentaltraitsforanindividual.

There is still a lot of controversy in personality research

overhowmanypersonalitytraitsthereare,buttheOCEAN

modelbyispopular[31]. SeeTable 1

Likethe othercognitiveprocessesdescribed,the modeling

ofpersonality mayleadtomoreconsistentcommunication,

andbecausepersonalityisapatternofbehavior(longertem-

poralextent)itshouldleadtomoreconsistentbehaviorfrom

situationtosituation.Thismayaidinobserversofthechar-

acter developingasense ofknowingthe character. It may

becomeanindividualinsteadofjustanothercomputerchar-

acter.

In spatial relations, introverts generally prefer greater in-

terpersonal distances. Aggressiveandviolence-proned (not

agreeable) individuals tend to need even greater interper-

sonaldistancesinordertofeelcomfortable. Introvertsalso

tendtoresistvisualinteraction. Peoplewho aremoreneu-

roticandintrovertedhavemorerestrainedandrigidbehav-

ior,anddisplaymoreuncoordinated,randommovements[6].

Thoughoftenpersonalitytraitsareconfusedwithemotions

inembodiedagents research,therehasbeenresearchdone

Openness Creative,Curious,Complex Conventional,Narrowinterests,Uncreative

Conscientiousness Reliable,Well-organized, Disorganized,Undependable,Negligent

Self-disciplined,Careful

Extraversion Sociable,Friendly,Fun-loving,Talkative Introverted,Reserved,Inhibited,Quiet

Agreeableness Goodnatured,Sympathetic, Critical,Rude,Harsh,Callous

Forgiving,Courteous

Neuroticism Nervous,High-strung,Insecure,Worrying Calm,Relaxed,Secure,Hardy

Table1: OCEAN ModelofPersonality

3.6 Interaction of Cognitive Processes

These cognitive processes can inuence and even conict

withoneanother. Anextremelyintrovertedperson,forex-

ample, isunlikelyto expressanger inthe same way as an

extrovertedperson. Anagreeablepersonislesslikelytofeel

angerortofeelitasintenselyasadisagreeableperson. Per-

hapspersonalityalsoinuencesthetypesof rolesaperson

performs. Wouldwewantanunconscientious,neuroticper-

sonasadoctor? Anintrovertedpersonwhoisforcedintoa

publicrolewouldfeeluncomfortable. Onlybyrepresenting

theagent'sinternal cognitive state, canwehope todepict

suchinteractionsand contradictions that resultinanxiety,

vacillation,orconfusion.

3.7 Individuals

What is important to people, what theyvalue, and what

theydesireare important aspectsof theirindividuality. at

anymomentaperson'sactionsaremotivatedbytheirgoals

andtheinteractionsandconictsoftheirgoals. Inorderto

achieveconsistentexternalactionsforembodiedagents,we

alsoneedtomodeltheirgoalsandtheprocessesinvolvedin

planningforgoalsandresolvingconictsbetweengoals. AI

researchhasstudiedmanyaspectsofplanningand conict

resolutioninplanning[26],butwhatismoveimportantfor

consistentcommunicationisthemanifestationofthesepro-

cessesinthechannelsofnonverbalcommunication.Imagine

ayoungchildwhose motherasks ifhepulledup all ofher

newly-planted owers. Thechild values being honest with

hismother,buthealsovaluesthedessertwhichwillbetaken

awayaspunishment. Hewillexpressconfusionandanxiety

ashedecideswhatto do. Themanifestationsofhiscogni-

tiveprocesseswillcommunicatevaluableinformationtohis

mother.

Aperson'sgoalsandtheirothercognitiveprocessesarere-

lated. Age inuencesan individual's perceptions, actions,

decisions. Dominant individuals tendto claim scarce and

desirable resources. In oursociety, malesare traditionally

thoughtofasmoretaskoriented,while femalesareconsid-

ered more interpersonal oriented. Culture helps in deter-

miningthe importance and immediacy of the activities of

life. Roles can be dened by what goals are valued while

theperson isperformingthe roles, and personality canbe

denedby whatgoals are valued and how thosegoals are

achievedthroughtime.

4. CONCLUSION

Studieshaveshownthatconsistencyinuencespeople'sre-

actionstoembodiedagents.Both[14,23]showedthatpeo-

plepreferconsistent characters andthatconsistentcharac-

seekingananimatedembodiedagentwithconsistencyboth

in terms of our expectations of human actions and com-

munications ingeneral and our expectationsof individual

humansinparticular. Webelievethat modelingthecogni-

tiveprocessesofembodiedagentsisastepinthisdirection,

and will facilitate the communicationof internal reective

statessuchasdetermination,confusion,andanxiety.

Wehavediscussedthetypeofcognitiveprocessesanembod-

iedagentshouldhaveinordertocreateconsistentcommuni-

cation. Wemustalsoaddresshowtocreateandcontrolthese

cognitiveprocesses. Ideallyour modelwill providevarying

levels of control. There are times whena virtual environ-

ment createwantstospecifyeverydetailofthe characters

behavior, and thereare othertimes whenhe orshe wants

autonomouscharacters. Weenvisionasystemwhereauser

setsonlytheparametersthattheyareinterestedin,andthe

systemsets therest. Forexample, ifauseronlydesires to

createacharacterwhoisclose-minded,unconscientious,ex-

troverted,disagreeable,andneurotic,thenthesystemwould

set theotherparametersbasedonthesepersonality traits.

This character, for example, might tend toward anger. If

therolesinthesystemincludednunandboxer,boxerwould

probablybechosen. Theusercouldalwaysgobackandx

settingsthatwereundesirable.

This paper has focused on nonverbal communication, but

thesechannels ofcommunicationwouldhaveto becoordi-

natedwithverbalcommunicationincludingvocabulary,tone

ofvoice,andintonation.

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