Modeling context- -aware distributed aware distributed Modeling - - PowerPoint PPT Presentation

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Modeling context Modeling context-

• aware distributed

aware distributed knowledge knowledge

Jorge Jorge Louçã Louçã

Jorge.L@ Jorge.L@iscte iscte.pt .pt ISCTE – Instituto Superior de Ciêncas do Trabalho e da Empresa

Lisboa, Portugal

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

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Agent Agent-

• Mediated Knowledge Management

Mediated Knowledge Management (AMKM 2003) (AMKM 2003)

San San Francisco Francisco, 2 , 24 4-

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Main G Main Goal

• al and Proposition

and Proposition

Research goal : to model multi-dimensional decision-making processes using artificial agents Propositions :

• use causal cognitive maps to model software agents
• compose a collective solution to a goal through a distributed and

incremental process, based on interactions

• use context in cognitive maps to define agent’s mental states

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

• n

Agent Agent-

• Mediated Knowledge Management

Mediated Knowledge Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

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Philosophy and artificial intelligence Philosophy and artificial intelligence

Philosophy and Artificial Intelligence: both try to understand all different kinds

• f perception, action and intelligence

The association of this domains allows :

• to simulate reasoning in software programs, starting from a given

conception of what can be the mind;

• to do controlled experiments aiming to understand the knowledge

representation systems used in our mind to represent the world; AI as a laboratory :

• a specified idea of what is the mind leads to experiments about new

software architectures

• experiments can be seen as a way of really doing philosophy, because

they search the conditions that make possible cognition in general - human intelligence

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

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Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

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Theoretical foundations: AI as a laboratory

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Intelligence: the capacity of problem solving and decision There is no problem solving and decision capacity without some representation of the world Folk Psychological Constructs help us to model the knowledge representation systems used by our mind, using mental states Advantages of Folk Psychology : operational, comprehensible, an instrument to predict and explain behavior, to manipulate mental states

Philosophy and artificial intelligence Philosophy and artificial intelligence

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

• n

Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

• 2

26 6 March March 200 2003 3

Theoretical foundations: AI as a laboratory

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Philosophy and artificial intelligence Philosophy and artificial intelligence

This use of mental states can act as a functionalist theory if we identify mental states in terms of their causal-functional relationships Functionalism identifies mental content with causal-functional roles [Goldman,93] Causal Covariance Theory of Content [Allen,02] proposes that mental states get their content by being causally related

• nly to what they are about (e.g., to those mental states belonging to its
• wn specific context)

This idea of using context to define mental states is adopted to manipulate mental states in a Multi-Agent System, through the use of Cognitive Maps

Theoretical foundations: Functionalism

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

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Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

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Goal Task State of the wold

++ Influence fortement positive + Influence positive

• Influence negative
• Influence fortement negative

Cognitive Mapping Cognitive Mapping

[Carlson et Walden,96]

Cognitive Map : graphical representation of individual or collective beliefs,

regarding a specific domain

Cognitive mapping is used by psychologists and decision makers to :

understand the behavior of actors participating in a decision making process detect conflicts (incoherent viewpoints) discuss points of view

very positive influence positive influence negative influence very negative influence

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

• n

Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

• 2

26 6 March March 200 2003 3

Theoretical foundations: using cognitive maps to model individual and collective beliefs

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Cognitive Mapping Cognitive Mapping

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

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Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

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• -

b1 - Adapt employees to changes e3 - Employees confidence e2 - Employees notion of "group" t5 - Dialogue t1 - Interact t3 - Accept suggestions t4 - Periodical reunions e1 - Age of employees : 30 / 35 t2 - Internal debates

(-,++)

e4 - Resistance to change working habitudes

+ + + ++ + (- -,++) +

b2 - Inovate working processes t6 - Create propositions

+ (+,++)

t7 - Research to improve working processes

++

t8 - Invest in R & D

++

t9 - Professionnal learning

(-,+) +

Reflexive character of CM - we each construct our private versions of reality and deal

• nly with those constructions, which may or may not correspond to some real world

[Lissack & Ross,99]

Example of a partial cognitive map [Louçã,00]

Theoretical foundations: using cognitive maps to model individual and collective beliefs

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Collective interpretation using CM - according to Karl Weick and others, organizations can also be seen, at another abstraction level, as systems

• f construction and interpretation of reality

[Weick,95] [Lissack & Gunz,99]

Different levels

• f

construction and interpretation of reality:

individual collective

Cognitive Mapping Cognitive Mapping

• -

b1 - Adapter le

personnel au changement

e3 - Confiance

du personnel

e2 - Cohésion

du personnel

t5 - Dialoguer t1 - Interagir t3 - Accepter

suggestions

t4 - Faire des

réunions périodiques

e1 - Age du

personnel : 30 / 35

t2 - Faire

réflexion interne

• e4 - Résistances à

changer d'habitudes de travail

+ + + ++ + ++ +

t9 - Faire formati

professionnelle

• -

+

CM facilitate reasoning, communication and discussion about individual and corporate knowledge

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

• n

Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

• 2

26 6 March March 200 2003 3

Theoretical foundations: using cognitive maps to model individual and collective beliefs

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[M arch an t, 9 9 ] [W ellm an , 9 4 a] [C o n so le et al.,8 9 ] [Z h an g et al., 9 2 et 9 4 ] [P ark & K im , 9 5 ] [C h aib - d raa, 9 7 a, 9 7 b et 9 8 ] IA d o m ain In feren ce fro m fu z zy im p licatio n C au sal in feren ce in q u alitativ e p ro b ab ilistic n etw o rk s In feren ce in cau sal n etw o rk s C au sal in feren ce ; M A S ; n eu ral n etw o rk s C au sal in feren ce w ith circu its C au sal in feren ce ; M A S F o rm al m o d el C o g n itiv e m ap as a lo g ical system C o gn itiv e M ap C au sal lin k as an im p licatio n fo rm u la N P N L o g ic L o g iq u e et R ela tio n s N P N L o g ic a n d R ela tio n s w ith circu its C o g n itiv e M ap K in d o f lin k s b etw een co n cep ts F u z zy im p licatio n P ro b ab ilistic cau sality C au sality C au sality C au sality C au sality R easo n in g fro m C o g n itiv e M ap s yes yes R easo n fro m cau sal n etw o rk s yes yes yes D etect an d so lv e co n flicts in M A S n o n o n o yes n o yes

Research in AI using Cognitive Maps Research in AI using Cognitive Maps

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

• n

Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

• 2

26 6 March March 200 2003 3

Theoretical foundations: state of the art

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Modeling Modeling context context-

• aware distributed knowledge

aware distributed knowledge

Individual solution to a goal

M a t r i x c

• m

p

• s

i t i

• n

Solution to an allocated goal Interaction Matrix

Evidence conflicts

• ---------------Cognitive Map Aggregation-------------------------

Solution to an allocated goal Solution to an allocated goal Collective Solution Collective Solution with conflicts

Goal allocation : results from other reasoning processes

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

• n

Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

• 2

26 6 March March 200 2003 3

Proposition: distributed and incremental reasoning process

An agent uses the set of concepts represented in its cognitive map. The agent composes its individual solution to the goal, represented by a partial cognitive map. Each agent that receives an allocation message including a sub-goal, starts its own reasoning process and, in return, responds with a solution to the sub-goal. This distributed reasoning process allows representing several points of view concerning the sub- goals.

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Modeling Modeling context context-

• aware distributed knowledge

aware distributed knowledge

Individual solution to a goal

M a t r i x c

• m

p

• s

i t i

• n

Solution to an allocated goal Interaction Matrix

Evidence conflicts

• ---------------Cognitive Map Aggregation-------------------------

Solution to an allocated goal Solution to an allocated goal Collective Solution Collective Solution with conflicts

Goal allocation : results from other reasoning processes

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

• n

Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

• 2

26 6 March March 200 2003 3

Proposition: an incremental, distributed and incremental reasoning process

The composition of the interaction matrix is done through the NPNe Methodology

• f

Aggregating Cognitive Maps [Louçã,02a]. Only the most acute opinions are considered to compose the collective solution. A link such as (+,--) evidences a conflict in the

• rganization.

This way, the collective reasoning mechanism will detect and evidence conflicts in the collective solution, graphically represented in the form

• f a cognitive map, allowing a

clear discussion and negotiation between the actors.

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Cognitive maps composed on one hand by concepts and by causal links between those concepts, in a strictu senso way [Weik,79] and on the other hand to consider the context of concepts, allowing some kind of inference This way, we can define mental states from cognitive maps by getting their content from the concepts being causally related to their context. More precisely, a mental state is represented by a concept and its context. In cognitive mapping terms we have : (1) concepts can’t be understood without context, (2) the context of a concept is composed by concepts that influence and that are influenced by the main concept and by links between those concepts, (3) each concept is coupled to its context, which can be called a scheme [Bougon & Komocar,94]

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

• n

Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

• 2

26 6 March March 200 2003 3

Propositions: cognitive maps standing for mental states

Modeling Modeling context context-

• aware distributed knowledge

aware distributed knowledge

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• -

b1 - Adapt employees to changes e3 - Employees confidence e2 - Employees notion of "group" t5 - Dialogue t1 - Interact t3 - Accept suggestions t4 - Periodical reunions e1 - Age of employees : 30 / 35 t2 - Internal debates

(-,++)

e4 - Resistance to change working habitudes

+ + + ++ + (- -,++) +

b2 - Inovate working processes t6 - Create propositions

+ (+,++)

t7 - Research to improve working processes

++

t8 - Invest in R & D

++

t9 - Professionnal learning

(-,+) +

Scheme – a concept and its context [Louçã,02]

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

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Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

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26 6 March March 200 2003 3

Propositions: cognitive maps standing for mental states

Modeling Modeling context context-

• aware distributed knowledge

aware distributed knowledge

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to interact agents communicate schemes communicating schemes influence agent’s mental states and develops collective knowledge

If concepts are not similar, then “CM aggregation”

If concepts are similar and if there are conflicts, then the graphical interface supports discussion (and argumentation) between individuals, to converge to a common scheme

Différents niveaux de détail dans la visualisation d’une solution collective avec mise en évidence de conflits

• -

• e4 - Résistances à

+ + + ++ + ++ + t9 - Faire formati

• -

+

Scheme

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

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Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

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26 6 March March 200 2003 3 Modeling

Modeling context context-

• aware distributed knowledge

aware distributed knowledge

Propositions: cognitive maps standing for mental states

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Application Application

Prototype and application in an industrial entreprise

These propositions above were tested in StrAgent, a distributed software system to support decision-making in human organizations

SETCOM – Electronica, S.A. (Palmela)

industrial enterprise in the domain of telecommunications and electronics Cognitive Maps were built from documents and interviews 5 teams - organisation, products, markets, human resources and information departments

Main goal : to model collective discussion and consensual decision

• to represent actors knowledge
• to show conflicts
• to support conflict resolution

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

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Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

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Conclusion Conclusion

A model of multi-dimensional reasoning in a multi-agent system is proposed. Cognitive maps are used as instruments to represent agent’s mental states. Schemes are used to compose a collective solution to a goal through a distributed and incremental process, based on agent’s interactions. The emergence of collective knowledge is represented in the cognitive map of each agent.

AAAI AAAI Spring Symposium Spring Symposium 2003 2003 on

• n

Agent Agent-

• Mediated Knowledge

Mediated Knowledge Management Management (AMKM 2003) (AMKM 2003) San San Francisco Francisco, 2 , 24 4-

• 2

26 6 March March 200 2003 3