25-26 Oct. 2001 , BNAIC’01

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An Alternative Classification of Agent Types based on BOID Conflict Resolution

Jan Broersen Mehdi Dastani Zisheng HuangJoris Hulstijn Leendert van der Torre

Utrecht UniversiteitVrije Universiteit Amsterdam

http://www.cs.vu.nl/~boid

25-26 Oct. 2001 , BNAIC’01

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Conflicts• Internal conflicts, e.g. between two desires

• External conflicts, e.g.:– if you go to Amsterdam, then you believe that there are

no cheap rooms close to the conference site– if you go to Amsterdam, then you are obliged to take a

cheap room– if you go to Amsterdam, then you desire to stay close to

the conference site– you intend to go to Amsterdam

• Agent type based on conflicts resolution

25-26 Oct. 2001 , BNAIC’01

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Layout of this Talk

• BOID architecture

• Conflicts and agent types

• Agent architectures and agent types

• Mapping agent types to agent architectures

• Examples

• Conclusion

25-26 Oct. 2001 , BNAIC’01

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BDI (e.g. R&G and C&L)

• Internal conflicts: axiomatizating each attitude– KD45 for beliefs; KD for desires and intentions

• External conflicts: axiomatizating relations between attitudes– Static: realism Inta() Bela() – Dynamic: commitment strategies

A(Inta(A) U(Bela() Bela(E)))

25-26 Oct. 2001 , BNAIC’01

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BDP (Thomason 2000)

• Beliefs and desires are (Reiter) defaults– Internal conflicts are possible

– { T p , T p } leads to multiple extensions

– In contrast to BDI: no modalities

• Wishful thinking:– { T rain , rain wet , T wet}

25-26 Oct. 2001 , BNAIC’01

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BOID architecture

Interpreter (Reasoner)

Obligations

Beliefs Desires

Intentions

Sensor

Effectors

Goal selection

Planning

25-26 Oct. 2001 , BNAIC’01

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Conflicts and Agent Types

• Realistic agent: beliefs override others

• Social agent: obligations override desires

• Selfish agent: desires override obligations

• Simple-minded agent: intentions override

obligations and desires (stable)

• Open-minded agent: desires and obligations override intentions

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B I O DObs.Goals

Social Simple Minded Agent Specialized Architecture 1

( rb ) < ( ri ) < ( ro ) < ( rd )

25-26 Oct. 2001 , BNAIC’01

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BI

OD

Super Selfish AgentSpecialized Architecture 2

( rb ) < ( rd ) < ( ri )

&( rb ) < ( rd ) < ( ro )

Obs. Goals

25-26 Oct. 2001 , BNAIC’01

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B<OB<IB<DI<D

B<OB<IB<DO<D

B<OB<IB<DI<O

B<OB<IB<DO<I

B<OB<IB<DD<O

B<OB<IB<DD<I

B<OB<IB<DI<DI<O

B<OB<IB<DO<DI<D

B<OB<IB<DO<IO<D

B<OB<IB<DI<OD<O

B<OB<IB<DD<ID<O

B<OB<IB<DO<ID<I

B<OB<IB<DI<DI<OO<D

B<OB<IB<DO<IO<DI<D

B<OB<IB<DI<DI<OD<O

B<OB<IB<DO<IO<DD<I

B<OB<IB<DD<ID<OI<O

B<OB<IB<DD<OD<IO<I

B<O , B<I , B<D

BO

ID

BIO

D

BID

O

BO

DI

BD

IO

BD

OI

BX

XI

BD

XX

BX

XO

BO

XX

BX

XD

BIX

X

25-26 Oct. 2001 , BNAIC’01

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O

D

Realistic AgentGeneral Architecture

Obs.B

I

Goals

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a r c

a c r T a

a r

a c

Example 1Social Simple-minded Agent

a = going to Amsterdamr = cheap room c = close to conference site

BO

I

D

25-26 Oct. 2001 , BNAIC’01

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a r c

a c r T a

a r

a c

Step 1Social Simple-minded Agent

a = going to Amsterdamr = cheap room c = close to conference site

BO

I

D

25-26 Oct. 2001 , BNAIC’01

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a r c

a c r T a

a r

a c

a = going to Amsterdamr = cheap room c = close to conference site

{a}

BO

I

D

Step 2Social Simple-minded Agent

25-26 Oct. 2001 , BNAIC’01

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T a

a r

a c

a = going to Amsterdamr = cheap room c = close to conference site

{a}

{a}a r c

a c r

BO

I

D

Step 3Social Simple-minded Agent

25-26 Oct. 2001 , BNAIC’01

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T a

a r

a c

a = going to Amsterdamr = cheap room c = close to conference site

{a}a r c

a c r

{a,r}BO

I

D

Step 4Social Simple-minded Agent

25-26 Oct. 2001 , BNAIC’01

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T a

a r

a c

a = going to Amsterdamr = cheap room c = close to conference site

a r c

a c r

{a,r}

{a,r,c}

BO

I

D

Step 5Social Simple-minded Agent

25-26 Oct. 2001 , BNAIC’01

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T a

a r

a c

a = going to Amsterdamr = cheap room c = close to conference site

a r c

a c r

{a,r,c}

{a,r,c}

BO

I

D

Step 6Social Simple-minded Agent

25-26 Oct. 2001 , BNAIC’01

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T a

a r

a c

a = going to Amsterdamr = cheap room c = close to conference site

a r c

a c r

{a,r,c}

{a,r,c}

BO

I

D

Step 7Social Simple-minded Agent

25-26 Oct. 2001 , BNAIC’01

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T a

a r

a c

Example 2Selfish Simple-minded Agent

a = going to Amsterdamr = cheap room c = close to conference site

a r c

a c r

{a,r,c}

BO

I

D

25-26 Oct. 2001 , BNAIC’01

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Conclusion• Benchmark examples for agent types• Norm, Conflicts, Agent types, Architectures• Small gap between architecture, logic and

implementation by mapping conflicts into agent architecture

Future Research• Extending architecture: planning and scheduling• Updating BOID rules• BOID verification and implementation

http://www.cs.vu.nl/~boid