Context
Technicity
Taste
Nutrition
WHAT TO DO ?
Easy-to-use
Security
Environment
Costs
Example
T65 ?
Millers
T80 ?
Bakers
Nutritionists
Consumers
Researchers
Government
(PNNS)
Example
T65 ?
Avoiding chemical contamination
T80 ?
Increasing nutritional components
Proposing a consumer-attractive bread
Decreasing costs
Limitating irritating fibers
Controling appetite
~60 identified arguments
Avoiding the responsability for consumer security
Maintaining sells
Preserving the profession’s technicity
Limitating salt consumption
Reducing costly widespread diseases
Questions
•
•
•
•
Models for formal representation ?
Support to analyse a complex situation ?
Methods for arbitration (compromise, …) ?
Explanations for a decision ?
Formal approach
2 existing frameworks of interest:
• Argumentation
• Multi-criteria decision
Combination of both = emerging issue
Argumentation
• Abstract argumentation framework (Dung, 1995)
(A,R) with:
- A a set of arguments
- R an attack relation
a
b
• Other elements: preferences, contexts, …
a
b
Argumentation
• An argument consists in:
- a set of assumptions (support or premises)
- a conclusion (claim or consequent)
- an implication: the conclusion can be deduced from
the assumptions
• Different kinds of attack:
- rebutting (negation of the conclusion)
- assumption attack (negation of the assumptions)
- undercutting (negation of the implication)
Prise de décision (Argumentation)
Example
 COM1 argument
T65 → T80
 economical
profit
Change in
color
Change in
texture
REBUTTING
 Satiety
Decreased
sales
 health
benefit
 COM2 argument
T65 → T80
awareness
campaign
 communication
on cereal
products
 economical
profit
Prise de décision (Argumentation)
Example
 NUTRI1 argument
 phytic acid
T65 → T80
ASSUMPTION
ATTACK
 biodisponibility
of essential
cations (Zn,Cu,…)
 health benefit
 NUTRI2 argument
T65 → T80
use of natural
yeast (sourdough)
 Acidity
 phytic
acid
Prise de décision (Argumentation)
Example
 PNNS argument (part of)
 Fibers
T65 → T80
 health
benefit
UNDERCUTTING
 NUTRI3 argument
 Fibers
T65 → T80
 insoluble
fibers
 health
benefit
Argumentation
• Notion of « extension »
• Several semantics:
- naïve extension: no conflicts + maximal
- admissible extension: no conflicts + defense
- preferred extension: no conflicts + defense + maximal
- complete extension: concerns self-defending arguments
- stable extension: no conflicts + attacks external arguments
- basic extension: recursively defined
Prise de décision (Argumentation)
Example
 Milling argument (MILL)
 extraction rate
 economical
profit
T65 → T80
 production
cost
 Baking argument (BAK)
 fibers
T65 → T80
 water
 flour
 economical
profit
Prise de décision (Argumentation)
Example
NUTRI3
PNNS
MILL
COM1
NUTRI1
BAK
COM2
NUTRI2
PREFERRED EXTENSIONS:
{COM1, NUTRI3, NUTRI2}
{COM2, MILL, BAK, PNNS, NUTRI2}
{COM2, MILL, BAK, NUTRI3, NUTRI2}
Argumentation-based decision
• Argument = {S,d,g} with:
- S the knowledge that supports the argument
- d the supported decision
- g a goal
(Amgoud and Prade, 2009)
• A simple mode of decision : choose the option
that is supported by most "acceptable"
arguments
Example
(d)
T65 ?
T65 contains less peripheric grain layers
 Avoiding chemical contamination
(S)
(g)
T65 produces more crusty breads
 Proposing a consumer-attractive bread
T65 contains more soluble fibers
 Limitating irritating fibers
T80 ?
Peripheric layers are rich in vitamins and minerals
 Increasing nutritional components
T80 bread requires less flour and more water
 Decreasing costs
First approach:
6 arguments versus 5
T65 provides less contammination risks
 T65
 Avoiding the responsability for consumer security
The market of T65 bread works well
 Maintaining sells
T65 involves complex fractionation steps by millers
 Preserving the profession’s technicity
T80 increases satiety
 Controling appetite
T80 is consumed in smaller quantities
 Limitating salt consumption
T80 participates in public health control
 Reducing costly widespread diseases
Example
(d)
T65 ?
T65 contains less peripheric grain layers
 Avoiding chemical contamination
(S)
(g)
most
T80 ?
informed
Peripheric layers are rich in vitamins and minerals
consumers’
1st goal  Increasing nutritional components
T65 produces more crusty breads consumers’
 Proposing a consumer-attractive bread st
1 goal
T65 contains more soluble fibers
 Limitating irritating fibers
T80 bread requires less flour and more water
bakers’
 Decreasing costs
1st goal
T80 increases satiety
 Controling appetite
Second approach:
nutritionists’
Satisfying most actors
T80 is consumed in smaller quantities
st goal
T65 provides less contammination risks
1
 T80
 Limitating salt consumption
 Avoiding the responsability for consumer security
The market of T65 bread works well millers’
1st goal
 Maintaining sells
T65 involves complex fractionation steps by millers
 Preserving the profession’s technicity
government’s
T80 participates in public health control
1st goal  Reducing costly widespread diseases
Unified approach
Example
Example
Conclusion
• A simplified example of a complex situation
• Different possible modes of decision
• Interest of the approach: theory, applications
and stakes
• Sensitive point: dependant on the quality of
arguments identification
Perspectives
• Decision with several viewpoints in the unified
approach
• A lot to do to facilitate visual representation and
analysis
• Towards a implemented tool