Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Argumentation in MAS
Carles Sierra1
1
Thanks to Leila Amgoud for the first part
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Outline
1
Argumentation
What is argumentation?
Abstract argumentation systems
2
Agents that reason and negotiate by arguing
3
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Argumentation-based approaches (Cont.)
John: Newspapers have no right to publish information I
Mary: Why ?
John: Because it is about X’s private life (a)
Mary: The information I is not private because X is a
minister and all information concerning ministers is public
(b)
John: But X is not a minister since he resigned last month
(c)
c
−→
b
−→
a
Question: Do newspapers have right to publish information I?
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Argumentation-based approaches (Cont.)
John: Newspapers have no right to publish information I
Mary: Why ?
John: Because it is about X’s private life (a)
Mary: The information I is not private because X is a
minister and all information concerning ministers is public
(b)
John: But X is not a minister since he resigned last month
(c)
c
−→
b
−→
a
Question: Do newspapers have right to publish information I?
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Argumentation-based approaches (Cont.)
John: Newspapers have no right to publish information I
Mary: Why ?
John: Because it is about X’s private life (a)
Mary: The information I is not private because X is a
minister and all information concerning ministers is public
(b)
John: But X is not a minister since he resigned last month
(c)
c
−→
b
−→
a
Question: Do newspapers have right to publish information I?
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Argumentation-based approaches (Cont.)
John: Newspapers have no right to publish information I
Mary: Why ?
John: Because it is about X’s private life (a)
Mary: The information I is not private because X is a
minister and all information concerning ministers is public
(b)
John: But X is not a minister since he resigned last month
(c)
c
−→
b
−→
a
Question: Do newspapers have right to publish information I?
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Argumentation-based approaches (Cont.)
John: Newspapers have no right to publish information I
Mary: Why ?
John: Because it is about X’s private life (a)
Mary: The information I is not private because X is a
minister and all information concerning ministers is public
(b)
John: But X is not a minister since he resigned last month
(c)
c
−→
b
−→
a
Question: Do newspapers have right to publish information I?
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Argumentation-based approaches (Cont.)
John: Newspapers have no right to publish information I
Mary: Why ?
John: Because it is about X’s private life (a)
Mary: The information I is not private because X is a
minister and all information concerning ministers is public
(b)
John: But X is not a minister since he resigned last month
(c)
c
−→
b
−→
a
Question: Do newspapers have right to publish information I?
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Argumentation-based approaches (Cont.)
John: Newspapers have no right to publish information I
Mary: Why ?
John: Because it is about X’s private life (a)
Mary: The information I is not private because X is a
minister and all information concerning ministers is public
(b)
John: But X is not a minister since he resigned last month
(c)
c
−→
b
−→
a
Question: Do newspapers have right to publish information I?
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
What is Argumentation?
Argumentation = a reasoning model based on the
exchange and the evaluation of arguments
Argument = a reason / justification for some claim
The core of an argument: Reasons + a claim
Reason: Because Tweety is a bird and birds fly
Claim: Tweety flies
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
What is Argumentation?
Argumentation = a reasoning model based on the
exchange and the evaluation of arguments
Argument = a reason / justification for some claim
The core of an argument: Reasons + a claim
Reason: Because Tweety is a bird and birds fly
Claim: Tweety flies
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
What is Argumentation?
Argumentation = a reasoning model based on the
exchange and the evaluation of arguments
Argument = a reason / justification for some claim
The core of an argument: Reasons + a claim
Reason: Because Tweety is a bird and birds fly
Claim: Tweety flies
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
What is Argumentation?
Argumentation = a reasoning model based on the
exchange and the evaluation of arguments
Argument = a reason / justification for some claim
The core of an argument: Reasons + a claim
Reason: Because Tweety is a bird and birds fly
Claim: Tweety flies
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
What is argumentation? (Cont.)
=⇒ Two types of arguments:
Epistemic arguments
They support beliefs
Practical arguments
They support decisions/proposals
Deductive reasoning
Abductive reasoning
Using conditional syllogism
P
If P then Q
Using practical syllogism
G is a goal for agent X
Doing action A is sufficient for agent X
to carry out goal G
Then, agent X ought to do action A
Therefore Q
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
What is argumentation? (Cont.)
=⇒ Two types of arguments:
Epistemic arguments
They support beliefs
Practical arguments
They support decisions/proposals
Deductive reasoning
Abductive reasoning
Using conditional syllogism
P
If P then Q
Using practical syllogism
G is a goal for agent X
Doing action A is sufficient for agent X
to carry out goal G
Then, agent X ought to do action A
Therefore Q
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
What is argumentation? (Cont.)
=⇒ Two types of arguments:
Epistemic arguments
They support beliefs
Practical arguments
They support decisions/proposals
Deductive reasoning
Abductive reasoning
Using conditional syllogism
P
If P then Q
Using practical syllogism
G is a goal for agent X
Doing action A is sufficient for agent X
to carry out goal G
Then, agent X ought to do action A
Therefore Q
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
What is argumentation? (Cont.)
=⇒ Two types of arguments:
Epistemic arguments
They support beliefs
Practical arguments
They support decisions/proposals
Deductive reasoning
Abductive reasoning
Using conditional syllogism
P
If P then Q
Using practical syllogism
G is a goal for agent X
Doing action A is sufficient for agent X
to carry out goal G
Then, agent X ought to do action A
Therefore Q
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
What is argumentation? (Cont.)
=⇒ Two types of arguments:
Epistemic arguments
They support beliefs
Practical arguments
They support decisions/proposals
Deductive reasoning
Abductive reasoning
Using conditional syllogism
P
If P then Q
Using practical syllogism
G is a goal for agent X
Doing action A is sufficient for agent X
to carry out goal G
Then, agent X ought to do action A
Therefore Q
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
What is argumentation? (Cont.)
Epistemic argument
cp
Practical argument
Big car is a goal
cp→ ca
Therefore ca
Polo→ Big car
Then, buyer ought to buy Polo
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Why study argumentation?
Internal agent’s reasoning:
1
2
3
4
5
6
Handling inconsistency in knowledge bases,
Merging information coming from different sources
Decision making
Goal generation and revision
Causality
Trust evaluation
Learning
Modeling interactions between agents:
1
2
3
4
Persuasion dialogs
Negotiation
Deliberation
Coalition formation
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems
Argumentation process =⇒ Four main steps
1
Constructing arguments
2
Defining the interactions between arguments
3
Defining the status of arguments
4
Concluding
Drawing conclusions using a consequence relation
Comparing decisions using a given principle
C. Sierra
Argumentation
→ Inference
→ Decision
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems
Argumentation process =⇒ Four main steps
1
Constructing arguments
2
Defining the interactions between arguments
3
Defining the status of arguments
4
Concluding
Drawing conclusions using a consequence relation
Comparing decisions using a given principle
C. Sierra
Argumentation
→ Inference
→ Decision
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems
Argumentation process =⇒ Four main steps
1
Constructing arguments
2
Defining the interactions between arguments
3
Defining the status of arguments
4
Concluding
Drawing conclusions using a consequence relation
Comparing decisions using a given principle
C. Sierra
Argumentation
→ Inference
→ Decision
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems
Argumentation process =⇒ Four main steps
1
Constructing arguments
2
Defining the interactions between arguments
3
Defining the status of arguments
4
Concluding
Drawing conclusions using a consequence relation
Comparing decisions using a given principle
C. Sierra
Argumentation
→ Inference
→ Decision
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems
Argumentation process =⇒ Four main steps
1
Constructing arguments
2
Defining the interactions between arguments
3
Defining the status of arguments
4
Concluding
Drawing conclusions using a consequence relation
Comparing decisions using a given principle
C. Sierra
Argumentation
→ Inference
→ Decision
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.) (Dung 1995)
An argumentation system is a pair hA, Ri where:
A = a set of arguments
R ⊆ A × A = an attack relation among arguments
Example 1.
Usually, Quakers are pacifist
Usually, Republicans are not pacifist
Nixon is both a Quaker and a Republican
=⇒ two arguments:
a : Nixon is a pacifist since he is a Quaker
b : Nixon is not a pacifist since he is a Republican
a
←→
C. Sierra
b
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.) (Dung 1995)
An argumentation system is a pair hA, Ri where:
A = a set of arguments
R ⊆ A × A = an attack relation among arguments
Example 1.
Usually, Quakers are pacifist
Usually, Republicans are not pacifist
Nixon is both a Quaker and a Republican
=⇒ two arguments:
a : Nixon is a pacifist since he is a Quaker
b : Nixon is not a pacifist since he is a Republican
a
←→
C. Sierra
b
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.) (Dung 1995)
An argumentation system is a pair hA, Ri where:
A = a set of arguments
R ⊆ A × A = an attack relation among arguments
Example 1.
Usually, Quakers are pacifist
Usually, Republicans are not pacifist
Nixon is both a Quaker and a Republican
=⇒ two arguments:
a : Nixon is a pacifist since he is a Quaker
b : Nixon is not a pacifist since he is a Republican
a
←→
C. Sierra
b
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.) (Dung 1995)
Which arguments to accept together? =⇒ acceptability
semantics
Let B ⊆ A.
B is conflict-free iff @a, b ∈ B such that (a, b) ∈ R
B defends an argument a iff ∀ b ∈ A, if (b, a) ∈ R, then ∃ c
∈ B such that (c, b) ∈ R
Example 2.
c
−→
b
−→
a
The set {c} is conflict-free and defends the argument A
The sets {a, b}, {b, c} and {a, b, c} are not conflict-free
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.) (Dung 1995)
Which arguments to accept together? =⇒ acceptability
semantics
Let B ⊆ A.
B is conflict-free iff @a, b ∈ B such that (a, b) ∈ R
B defends an argument a iff ∀ b ∈ A, if (b, a) ∈ R, then ∃ c
∈ B such that (c, b) ∈ R
Example 2.
c
−→
b
−→
a
The set {c} is conflict-free and defends the argument A
The sets {a, b}, {b, c} and {a, b, c} are not conflict-free
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.) (Dung 1995)
Which arguments to accept together? =⇒ acceptability
semantics
Let B ⊆ A.
B is conflict-free iff @a, b ∈ B such that (a, b) ∈ R
B defends an argument a iff ∀ b ∈ A, if (b, a) ∈ R, then ∃ c
∈ B such that (c, b) ∈ R
Example 2.
c
−→
b
−→
a
The set {c} is conflict-free and defends the argument A
The sets {a, b}, {b, c} and {a, b, c} are not conflict-free
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.) (Dung 1995)
Which arguments to accept together? =⇒ acceptability
semantics
Let B ⊆ A.
B is conflict-free iff @a, b ∈ B such that (a, b) ∈ R
B defends an argument a iff ∀ b ∈ A, if (b, a) ∈ R, then ∃ c
∈ B such that (c, b) ∈ R
Example 2.
c
−→
b
−→
a
The set {c} is conflict-free and defends the argument A
The sets {a, b}, {b, c} and {a, b, c} are not conflict-free
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.) (Dung 1995)
Which arguments to accept together? =⇒ acceptability
semantics
Let B ⊆ A.
B is conflict-free iff @a, b ∈ B such that (a, b) ∈ R
B defends an argument a iff ∀ b ∈ A, if (b, a) ∈ R, then ∃ c
∈ B such that (c, b) ∈ R
Example 2.
c
−→
b
−→
a
The set {c} is conflict-free and defends the argument A
The sets {a, b}, {b, c} and {a, b, c} are not conflict-free
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.) (Dung 1995)
Which arguments to accept together? =⇒ acceptability
semantics
Let B ⊆ A.
B is conflict-free iff @a, b ∈ B such that (a, b) ∈ R
B defends an argument a iff ∀ b ∈ A, if (b, a) ∈ R, then ∃ c
∈ B such that (c, b) ∈ R
Example 2.
c
−→
b
−→
a
The set {c} is conflict-free and defends the argument A
The sets {a, b}, {b, c} and {a, b, c} are not conflict-free
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Admissible extensions (Dung 1995)
Let B ⊆ A. B is an admissible extension iff
1
2
B is conflict-free
B defends all its elements
Example 1. (Cont.)
a
←→
b
∅, {a}, {b} are admissible extensions
{a, b} is not an admissible extension
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Admissible extensions (Dung 1995)
Let B ⊆ A. B is an admissible extension iff
1
2
B is conflict-free
B defends all its elements
Example 1. (Cont.)
a
←→
b
∅, {a}, {b} are admissible extensions
{a, b} is not an admissible extension
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Admissible extensions (Dung 1995)
Let B ⊆ A. B is an admissible extension iff
1
2
B is conflict-free
B defends all its elements
Example 1. (Cont.)
a
←→
b
∅, {a}, {b} are admissible extensions
{a, b} is not an admissible extension
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Stable extensions (Dung 1995)
Let B ⊆ A. B is a stable extension iff
1
2
B is conflict-free
B attacks any argument in A\B
Example 1. (Cont.)
a
←→
b
{a}, {b} are stable extensions
∅, {a, b} are not stable extensions
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Stable extensions (Dung 1995)
Let B ⊆ A. B is a stable extension iff
1
2
B is conflict-free
B attacks any argument in A\B
Example 1. (Cont.)
a
←→
b
{a}, {b} are stable extensions
∅, {a, b} are not stable extensions
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Stable extensions (Dung 1995)
Let B ⊆ A. B is a stable extension iff
1
2
B is conflict-free
B attacks any argument in A\B
Example 1. (Cont.)
a
←→
b
{a}, {b} are stable extensions
∅, {a, b} are not stable extensions
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Stable extensions (Cont.) (Dung 1995)
Let B ⊆ A. B is a stable extension iff
1
2
B is conflict-free
B attacks any argument in A\B
Example 3.
a
%
c
&
←−
b
e
No stable extension =⇒ no accepted argument
We would like to accept the argument e since it is not
attacked
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Stable extensions (Cont.) (Dung 1995)
Let B ⊆ A. B is a stable extension iff
1
2
B is conflict-free
B attacks any argument in A\B
Example 3.
a
%
c
&
←−
b
e
No stable extension =⇒ no accepted argument
We would like to accept the argument e since it is not
attacked
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Preferred extensions (Dung 1995)
Let B ⊆ A. B is a preferred extension iff
1
2
B is an admissible extension
B is maximal for set inclusion among admissible extensions
Example 3. (Cont.)
a
%
&
←−
c
b
One preferred extension =⇒ {e}
Thus, e is accepted
C. Sierra
Argumentation
e
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Preferred extensions (Dung 1995)
Let B ⊆ A. B is a preferred extension iff
1
2
B is an admissible extension
B is maximal for set inclusion among admissible extensions
Example 3. (Cont.)
a
%
&
←−
c
b
One preferred extension =⇒ {e}
Thus, e is accepted
C. Sierra
Argumentation
e
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Preferred extensions (Dung 1995)
Let B ⊆ A. B is a preferred extension iff
1
2
B is an admissible extension
B is maximal for set inclusion among admissible extensions
Example 3. (Cont.)
a
%
&
←−
c
b
One preferred extension =⇒ {e}
Thus, e is accepted
C. Sierra
Argumentation
e
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.)
What is the status of an argument a in A?
E1 , . . . , Ek = the extensions (under a given semantics) of
hA, Ri.
a is skeptically accepted iff ∀Ei=1,...,k , a ∈ Ei
a is credulously accepted iff ∃Ei such that a ∈ Ei
a is rejected iff @Ei such that a ∈ Ei
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.)
What is the status of an argument a in A?
E1 , . . . , Ek = the extensions (under a given semantics) of
hA, Ri.
a is skeptically accepted iff ∀Ei=1,...,k , a ∈ Ei
a is credulously accepted iff ∃Ei such that a ∈ Ei
a is rejected iff @Ei such that a ∈ Ei
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.)
What is the status of an argument a in A?
E1 , . . . , Ek = the extensions (under a given semantics) of
hA, Ri.
a is skeptically accepted iff ∀Ei=1,...,k , a ∈ Ei
a is credulously accepted iff ∃Ei such that a ∈ Ei
a is rejected iff @Ei such that a ∈ Ei
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.)
What is the status of an argument a in A?
E1 , . . . , Ek = the extensions (under a given semantics) of
hA, Ri.
a is skeptically accepted iff ∀Ei=1,...,k , a ∈ Ei
a is credulously accepted iff ∃Ei such that a ∈ Ei
a is rejected iff @Ei such that a ∈ Ei
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.)
What is the status of an argument a in A?
E1 , . . . , Ek = the extensions (under a given semantics) of
hA, Ri.
a is skeptically accepted iff ∀Ei=1,...,k , a ∈ Ei
a is credulously accepted iff ∃Ei such that a ∈ Ei
a is rejected iff @Ei such that a ∈ Ei
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.)
Example 1 (Cont.)
a
←→
b
{a}, {b} are the stable extensions of the system
the two arguments a and b are credulously accepted
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
What is argumentation?
Abstract argumentation systems
Abstract argumentation systems (Cont.)
Example 3 (Cont.)
a
%
c
&
←−
b
e
{e} is the only preferred extension of the system
the argument e is skeptically accepted
The arguments a, b, c are rejected
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Introduction
Negotiation is a process that takes place between two or more
agents who are attempting to achieve goals which they cannot,
or prefer not to, achieve on their own.
A proposal, is some kind of solution to the problem that the
agents face. It may be a single complete solution, single partial
solution, or a group of complete or partial solutions.
A critique may just be a remark as to whether or not the
proposal is accepted or a comment on which parts of the
proposal the agent likes, and which parts it dislikes. A more
complex kind of critique is a counter-proposal.
An explanation is additional information explaining why a
proposal was made that an agent can supply in support of its
proposal.
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Generic multi-context agents
Units: Structural entities representing the main
components of the architecture.
Logics: Declarative languages, each with a set of axioms
and a number of rules of inference. Each unit has a single
logic associated with it.
Theories: Sets of formulae written in the logic associated
with a unit.
Bridge rules: Rules of inference which relate formulae in
different units.
Agent = h{ui }i∈I , ∆i where I is the set of unit indices,
ui = hLi , Ai , ∆i i, where Li , Ai and ∆i respectively are the
language, axioms and rules of inference defining the logic, and
∆ is the set of all bridge rules between the units.
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Examples of Bridge rules
u1 : ϕ, u2 : ψ ⇒ u3 : θ
I : I(α) ⇒ B : B(dI(α)e)
For instance, we can declare a metapredicate (T ) and then by
means of bridge rules define which terms the predicate will
apply over. The following:
u1 : p ⇒ u2 : T (atom(p))
is a bridge rule which embeds atoms of the theory of unit u1
into the propositional metatheory of unit u2 , and:
u2 : p(X , a) ⇒ u3 : T (literal(name(p), args(variable(X ), constant(a)))
does a similar job in the case of a first order language defined
as a metalanguage for u2 in u3 .
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Execution model
An agent’s deductive mechanism, `i , can be realised by the use
of an execution model based on the following assumptions:
1
Concurrency. The execution of each unit is a
non-terminating deductive process (which may be
formulated using dynamic logic (or π-calculus)). All units
execute concurrently as well as the bridge rules. They
examine the theories of the units in their premises for sets
of formulae that match them, whenever a new match is
found the concluding formula is asynchronously added to
the theory of its associated unit.
2
Reactivity. The communication unit immediately processes
(and thus adds to its theory) all messages it receives from
other agents.
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Multi-context BDI Agents
Strong realism. The set of intentions is a subset of the set
of desires which in turn is a subset of the beliefs. That is, if
an agent does not believe something, it will neither desire
nor intend it.
Realism. The set of beliefs is a subset of the set of desires
which in turn is a subset of the set of intentions. That is, if
an agent believes something, it both desires and intends it.
Weak realism. A case in between strong realism and
realism. Agents do not desire properties the negation of
which are believed, do not intend propositions the
negations of which are desired, and do not intend
propositions the negations of which are believed.
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Home Improving agents
: Ia (Can(a, hang(picture)))
(1)
B
I
: Ba (Have(a, picture))
(2)
B
: Ba (Have(a, screw))
(3)
B
: Ba (Have(a, hammer ))
(4)
B
: Ba (Have(a, screwdriver ))
(5)
B
: Ba (Have(b, nail))
(6)
B
: Ba (Have(X , hammer ) ∧ Have(X , nail) ∧ Have(X , picture) →
Can(X , hang(picture)))
B
(7)
: Ba (Have(X , screw) ∧ Have(X , screwdriver ) ∧ Have(X , mirror ) →
Can(X , hang(mirror )))
C. Sierra
(8)
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Home Improving agents (cntd)
I
: Ib (Can(b, hang(mirror )))
(9)
B
: Bb (Have(b, mirror ))
(10)
B
: Bb (Have(b, nail))
(11)
B
: Bb (Have(X , hammer ) ∧ Have(X , nail) ∧ Have(X , mirror ) →
Can(X , hang(mirror )))
C. Sierra
(12)
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
A simple theory of action
Ownership. When an agent (X) is the owner of an artifact (Z)
and it gives Z to another agent (Y), Y becomes its
new owner:
B : Bi (Have(X , Z ) ∧ Give(X , Y , Z ) → Have(Y , Z ))
(13)
Unicity. When an agent (X) gives an artifact (Z) away, it no
longer owns it:
B : Bi (Have(X , Z )∧Give(X , Y , Z ) → ¬Have(X , Z ))
(14)
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
A simple theory of action (cntd)
Benevolence. When an agent i has something (Z) that it does
not intend to use and is asked to give it to another
agent (X), i adopts the intention of giving Z to X:
B : Bi (Have(i, Z ) ∧ ¬Ii (Have(i, Z ))
∧Ask(X , i, Give(i, X , Z )) →
Ii (Give(i, X , Z )))
C. Sierra
Argumentation
(15)
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
A simple theory of planning
Parsimony. If an agent believes that it does not intend
something, it does not believe that it will intend the
means to achieve it.
B : Bi (¬Ii (Q)) ∧ Bi (P1 ∧ · · · ∧ Pj ∧ · · · ∧ Pn → Q) → ¬Bi (Ii (Pj ))
Reduction. If there is only one way of achieving an intention,
an agent adopts the intention of achieving its
preconditions.
B : Bi (Ii (Q)) ∧ Bi (P1 ∧ · · · ∧ Pj ∧ · · · ∧ Pn → Q)
∧ ¬Bi (R1 ∧ . . . ∧ Rm → Q) → Bi (Ii (Pj ))
C. Sierra
Argumentation
(16)
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
A simple theory of planning (cntd)
Unique Choice. If there are two or more ways of achieving an
intention, only one is intended. Note that we use
5 to denote exclusive or.
B : Bi (Ii (Q)) ∧ Bi (P1 ∧ · · · ∧ Pj ∧ · · · ∧ Pn → Q)∧
Bi (R1 ∧ . . . ∧ Rm → Q) →
Bi (Ii (P1 ∧ · · · ∧ Pn )) 5 Bi (Ii (R1 ∧ · · · ∧ Rm ))(17)
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Some bridge rules
Request. When an agent (i) needs something (Z) from
another agent (X), it asks for it:
I : Ii (Give(X , i, Z )) ⇒ C : Ask(i, X , Give(X , i, Z ))
(18)
Offer. When an agent (i) has the intention of offering
something (Z) to another agent (X), it informs the
recipient of this fact:
I : Ii (Give(i, X , Z )) ⇒ C : Tell(i, X , Give(i, X , Z ))
(19)
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Some bridge rules (cntd)
Trust. When an agent (i) is told of a belief of another
agent (X), it accepts that belief:
C : Tell(X , i, BX (ϕ)) ⇒ B : Bi (ϕ)
(20)
Awareness of intentions. Agents are aware of their intentions.
I : Ii (α) ⇒ B : Bi (Ii (α))
(21)
I : ¬Ii (α) ⇒ B : Bi (¬Ii (α))
(22)
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
More bridge rules
Awareness of illocutions. Agents are aware of the
requirements received by the communication unit.
C : α ⇒ B : Bi (α)
(23)
Impulsiveness. When an agent believes it has an intention, it
adopts that intention.
B : Bi (Ii (α)) ⇒ I : Ii (α)
C. Sierra
Argumentation
(24)
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Multi-context multi-agent argumentation
Argumentation is summarised by the following schema:
Γ ` (ϕ, G)
where Γ is the set of formulae available for building arguments,
` is a suitable consequence relation, ϕ is the proposition for
which the argument is made and G indicates the set of
formulae used to infer ϕ, G ⊆ Γ.
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Multi-context multi-agent argumentation (cntd)
We use:
Γ `d ϕ
with d = a{r1 ,...,rn } , to mean that the formula ϕ is deduced by
agent a from the set of formulae Γ by using the set of inference
rules or bridge rules {r1 , . . . , rn }. For instance:
{I : Ia (Give(b, a, nail))} `a{18}
{I : p, I : p → q} `a{mp}
C. Sierra
C : Ask(a, b, Give(b, a, nail))
I:q
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Some definitions
Definition
Given an agent a, an argument for a formula ϕ is a pair (ϕ, P)
where P = {s1 , . . . , sn } and either si is a formula in the theories
of agent a or si = Γi `di ψ and pj ∈ Γi is either a formula in the
theories of a or the conclusion of a previous step in P, and ψ is
a formula in the language of a, and sn = Γn `dn ϕ.
Definition
We say that an argument (ϕ, P) is consistent if there are no
si , sj ∈ P such that si = Γi `di ψ and sj = Γj `dj ¬ψ
Definition
An argument (ϕ, P) is non-trivial if it is consistent.
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
More definitions
Definition
An argument (ϕ, P) is tautological if all deductive steps in P are
built using only rules of inference, bridge rules and axioms of
the logics of the agent’s units.
Definition
An argument (ϕi , Pi ) rebuts an argument (ϕj , Pj ) if ϕi attacks
ϕj .
Definition
An argument (ϕi , Pi ) undercuts an argument (ϕj , Pj ) if there
exists sk ∈ Pj such that (1) sk is a formula and ϕi attacks sk , or
(2) sk = Γk `dk ψ and ϕi attacks ψ
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Selection
A1 The class of all arguments that may be made from Γ.
A2 The class of all non-trivial arguments made from Γ.
A3 The class of all arguments that may be made from Γ for
propositions for which there are no rebutting arguments
that may be made from Γ.
A4 The class of all arguments that may be made from Γ for
propositions for which there are no undercutting arguments
that may be made from Γ.
A5 The class of all tautological arguments made from Γ.
Informally, the idea is that arguments in higher numbered
classes are more acceptable because they are less
questionable.
A5 (Γ) ⊆ A4 (Γ) ⊆ A3 (Γ) ⊆ A2 (Γ) ⊆ A1 (Γ)
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Attack in BDI Agents
In our BDI agents, there is no conflict between an agent which
believes ϕ, that is Bi (ϕ), and one which believes ¬ϕ, that is
Bj (¬ϕ). Conflicts only occur when:
1
agents have opposite intentions, or
2
one agent intends to change a particular mental state in
another agent.
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Attack in BDI Agents (cndtd)
That is:
1
Ii (ϕ) attacks Ij (¬ϕ). For example, the fact “Carles intends
to be Prime Minister”, ICarles (Prime(Carles)), attacks the
fact “Simon intends that Carles is not Prime Minister”,
ISimon (¬Prime(Carles)).
2
Ii (Mj (ϕ)) attacks Mj (¬ϕ). For example, the fact “Kate
intends that Simon believes that God exists”,
IKate (BSimon (God)), attacks the fact “Simon believes that
God does not exist”, BSimon (¬God).
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Definition of attack in BDI Agents
Definition
Given agents i and j, we say that a formula ϕi of the language
of agent i attacks a formula ϕj of the language of agent j if one
of following cases hold:
1
ϕi = Ii (ϕ) and ϕj = Ij (¬ϕ)
2
ϕi = Ii (Mj1 (Mj2 (. . . (Mjn (ϕ)) . . . ))) and
ϕj = Mj1 (. . . (¬Mjk (. . . (Mjn (ϕ)) . . . )) . . . ) with 1 ≤ k ≤ n or
ϕj = Mj1 (Mj2 (. . . (Mjn (¬ϕ)) . . . )).
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Negotiation as argumentation
1
Selection by agent a of an intention to be satisfied, Ia (ϕ).
2
Looking for a proof for Ia (ϕ) based on its own resources. If possible,
finish.
3
If not possible, start a negotiation with the owner of the resource(s), b
4
Agent a builds an argument (ψa , Pa ) and sends it to b
5
Agent b then examines (ψa , Pa ). If it agrees, finish
6
If b disagrees
1
2
b can build an argument (ψb , Pb ) such that ψb attacks ψa .
b can build an undercutting argument (ψb0 , Pb0 ) for (ψa , Pa ).
Because ψa conflicts with one of b’s intentions (Definition 7
case 1), or because a made an incorrect assumption about
one of b’s beliefs (Definition 7 case 2).
In either case b informs a of its attacking argument.
7
Iterate the negotiation.
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Example. Step 1
Step 1: Agent a tries to find a proof for Can(a, hang(picture)) because of its
intention Ia (Can(a, hang(picture))). Agent a builds an argument
(Ia (Give(b, a, nail)), Pa )
where Pa is:
{Ia (Can(a, hang(picture)))}
`21
Ba (Ia (Can(a, hang(picture))))
(25)
{(25), (16), (7)}
`mp
Ba (Ia (Have(a, nail)))
(26)
{(6), (13)}
`mp
Ba (Give(b, Y , nail) → Have(Y , nail))
(27)
{(27), (26), (16)}
`mp
Ba (Ia (Give(b, a, nail)))
(28)
{(28)}
`24
Ia (Give(b, a, nail))
(29)
This is then converted into an action using bridge rule 18
{(29)} `18 Ask (a, b, Give(b, a, nail))
When agent a generates the argument (Ia (Give(b, a, nail)), Pa ) it is placed in
acceptability class A4 since a cannot build any undercutting arguments
against it and so a deems it to be a suitable suggestion to be passed to b.
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Example: Step 2
Step 2: Unit C of agent b receives the formula Ask(a, b, Give(b, a, nail)),
which, as specified, brings with it the argument:
(Ia (Give(b, a, nail)), {(25), (26), (27), (28), (29)})
Now, agent b has its own goal, Ib (Can(b, hang(mirror ))), which as we will
see forms the basis of its argument:(Ib (¬Give(b, a, nail)), Pb ) where Pb :
{Ib (Can(b, hang(mirror )))}
`21
Bb (Ib (Can(b, hang(mirror )))) (30)
{(30), (12), (16)}
`mp
Bb (Ib (Have(b, nail)))
(31)
{(31), (14)}
`mt
Bb (Ib (¬Give(b, Y , nail)))
(32)
{(32)}
`pt
Bb (Ib (¬Give(b, a, nail)))
(33)
This argument rebuts the argument for Ia (Give(b, a, nail)). This means that
for agent b both arguments are in class A2 (since they mutually rebut one
another but they are consistent). Assuming rationality, b prefers the second
argument since this enables it to satisfy one of its intentions (hanging the
mirror). b will return the second argument to a as a critique.
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Example: Step 3
Step 3: In response, agent a generates a new argument which provides an
alternative way of hanging the mirror that will satisfy b’s goal without using
the nail:
(Ba (¬Ib (Have(b, nail))), Pa0 )
0
where Pa is:
{¬Ia (Can(a, hang(mirror )))}
`22
Ba (¬Ia (Can(a, hang(mirror ))))
{(34), (16), (8)}
`mp
¬Ba (Ia (Have(a, screw)))
{(35)}
`sr
¬Ia (Ia (Have(a, screwdriver )))
∧ ¬Ba (Ia (Have(a, screwdriver )))
∧ ¬Ia (Ia (Have(a, screw)))
{(35), (3), (5), (15)}
`mp,pt
(34)
(35)
(36)
Ba (Ask (b, a, Give(a, b, screw)) →
Ia (Give(a, b, screw)))
∧ Ba (Ask (b, a, Give(a, b, screwdriver )) →
Ia (Give(a, b, screwdriver )))
C. Sierra
Argumentation
(37)
(38)
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Example: Step 3
{(37), (8)}
`mp
Ba (Ask (b, a, Give(a, b, screw))
∧ Ask(b, a, Give(a, b, screwdriver ))
{(17), (39), (12)}
`mp
→ Can(b, hang(mirror )))
(39)
Ba (¬Ib (Have(b, nail)))
(40)
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Crucial points:
1
This argument is classified in A4 by a that sends it to b. Agent b
classifies it in A4 .
2
b cannot construct a rebuttal for the new argument as a subargument of
its previous argument because it can no longer use the reduction
planning rule (16). Moreover, the second argument can no longer be
maintained for the same reason, so a’s original argument is reclassified
as being in A4 . Hence agent a will receive the nail, agent b will ask for
the screw and the screwdriver and both will reach their goals.
3
Note that step 36 is crucial in the construction of the undercutting
argument. This step depends upon the fact that agent a has the bridge
rules associated with strong realism and so can go from
¬Ba (Ia (Have(a, screw))) to ¬Da (Ia (Have(a, screw))) and hence to
¬Ia (Ia (Have(a, screw))).
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Open questions
To study the properties of protocols allowing to reach
optimal solutions
How an optimal solution can be reached quickly?
A need of a meta-model of decision making for choosing
the next move to play in a dialogue
A need of a general framework for multi-attributes
negotiations
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
The home improving agents
C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Bibliography
L. Amgoud, Y. Dimopoulos, and P. Moraitis. A Unified and General
Framework for Argumentation-based Negotiation. AAMAS’2007.
L. Amgoud, S. Parsons, and N. Maudet. Arguments, dialogue, and
negotiation. ECAI’ 2000.
L. Amgoud and H. Prade. Explaining qualitative decision under
uncertainty by argumentation. AAAI’06.
P. M. Dung. On the acceptability of arguments and its fundamental role
in nonmonotonic reasoning, logic programming and n-person games.
AIJ’1995.
N. R. Jennings, P. Faratin, A. R. Lumuscio, S. Parsons, and C. Sierra.
Automated negotiation: Prospects, methods and challenges.
International Journal of Group Decision and Negotiation, 2001.
A. Kakas and P. Moraitis. Adaptive agent negotiation via argumentation.
AAMAS’2006.
C. Sierra
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The home improving agents
Bibliography (Cont.)
S. Kraus, K. Sycara, and A. Evenchik. Reaching agreements through
argumentation: a logical model and implementation. AIJ’1998.
S. Parsons and N. R. Jennings. Negotiation through argumentationa
preliminary report. ICMAS’1996.
I. Rahwan, S. D. Ramchurn, N. R. Jennings, P. McBurney, S. Parsons,
and E. Sonenberg. Argumentation-based negotiation. Knowledge
Engineering Review, 18 (4):343375, 2003.
J. Rosenschein and G. Zlotkin. Rules of Encounter: Designing
Conventions for Automated Negotiation Among Computers,. MIT Press,
Cambridge, Massachusetts, 1994., 1994.
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C. Sierra
Argumentation
Argumentation
Agents that reason and negotiate by arguing
The home improving agents
Thank you
Questions
C. Sierra
Argumentation