IIIA - Artificial Intelligence Research Institute CSIC – Spanish Council for Scientific Research Deliverable 2.1: e-Institutions oriented to the use of reputation Jordi Sabater-Mir Isaac Pinyol Daniel Villatoro Guifré Cuní Carles Sierra Juan Antonio Rodriguez Josep Lluís Arcos WP2 – Tools development

IIIA-CSIC Annex I: 1.Using the tool for e-institutions developed by partner number 4, study and design of the extra elements that are necessary to facilitate and study the use of reputation in an e-institution environment. 2.Development of an alpha version of the e-institution tool for reputation modelling. 3.Help to develop the applications allowing the different experiments described in the rest of workpackages to be run. Corresponding deliverables list: T (D2.1): e-Institutions oriented to the use of Reputation T (D2.2): e-Institution reputation software

E-Institutions IIIA-CSIC In human societies, institutions regulate the behaviour of people by enforcing laws, fixing protocols, etc. Open multiagent systems are populated by autonomous entities and therefore, there is no guarantee about what will be the behaviour of these entities. An e-institutions is the electronic equivalent of a traditional institution but for virtual environments.

E-Institutions IIIA-CSIC Some vocabulari: Role. Standardised patterns of behaviour required by all agents playing part in a given functional relationship. Dialogic Framework. Ontological elements and communication language (ACL) employed during an agent interaction. Scene. Agents meetings whose interaction is shaped by a well-defined protocol. Performative Structure. Complex activities specified as connections among scenes. Normative rules. Define the consequences of the agent actions within scenes.

E-Institutions IIIA-CSIC Performative structure Scenes Institutional agents

E-Institutions IIIA-CSIC governor

E-Institutions IIIA-CSIC

Using reputation in e-institutions IIIA-CSIC Integration of reputation mechanisms in the eI. Integration of a cognitive agent architecture in the context of an eI. Specification and implementation of a common ontology for reputation. Human interface with the eI.

IIIA-CSIC Integration of reputation mechanisms Centralized reputation (eBay, Sporas...) Distributed reputation (RepAge, ReGreT...) E-Institution Agent Governor Rep. system E-Institution Agent Governor Rep. system eI-service

Using reputation in e-institutions IIIA-CSIC Integration of reputation mechanisms in the eI. Integration of a cognitive agent architecture in the context of an eI. Specification and implementation of a common ontology for reputation. Human interface with the eI.

IIIA-CSIC EIAgent architecture

IIIA-CSIC EIAgent architecture

IIIA-CSIC Jadex architecture

IIIA-CSIC Jadex architecture

IIIA-CSIC Jadex architecture

IIIA-CSIC Jadex architecture

Using reputation in e-institutions IIIA-CSIC Integration of reputation mechanisms in the eI. Integration of a cognitive agent architecture in the context of an eI. Specification and implementation of a common ontology for reputation. Human interface with the eI.

CTR 1 CTR 2 CTR 3 OK! ??? ? ? ? The problem What if agents using different reputation models are in the same community? Different semantics, different representation of evaluations…. Pepe is Good? Pepe is 0.7? Pepe is 5? IIIA-CSIC

Let’s speak the same language! CTR 1 CTR 2 Ontology Mapping for CTR 1 Common Reputation Ontology Ontology Mapping for CTR 2 Communication IIIA-CSIC

The Ontology: Social Evaluation Evaluation Target Strength Value Context Source Entity Focus has belongs to Value [0,1]  R belongs to Voice Eval. Gossiper Recipient belongs to has 0..1 has belongs to Norm Single Agent Group Institution is Skill Standard is IIIA-CSIC

The Ontology: Evaluative Belief Voice has belongs to 1 Eval. EvaluationEntity Entities has belongs to 1..n 1 Eval. Evaluation Entity EntitiesVoice IdTransEval. Real has belongs to 1 1..n 111 Reputation SharedImage ImageDExperienceSharedVoice EvalBelief SimpleBelief MetaBelief is IIIA-CSIC

Value Representation Evaluation Target Context Value Strength Source Entity Focus has belongs to [0,1]  R Value belongs to Voice Eval. Gossiper Recipient belongs to has 0..1 has belongs to - Accuracy + Boolean False/True Discrete Sets {VB, B, N, G, VG} Probability Distribution Fuzzy Sets VBBNGVG Value Bounded Real [0,1] IIIA-CSIC

Boolean {False,True} Discrete Sets {VB, B, N, G, VG} Probability Distribution VBBNGVG Value Bounded Real [0,1] Max Min goodness FalseTrue Max Min goodness VBBNGVG Max Min goodness BooleanDiscrete Set Bounded Real VBBNGVG 0 1 VBBNGVG 0 1 Prob. Distribution Min Max Semantic of the representations IIIA-CSIC

Conversions between types VBBNGVG Some of them… X ≥ 0.5 VG0.9 G0.7 N0.5 B0.3 VB0.1 [0.8,1)VG [0.6,0.8)G [0.4,0.6)N [0.2,0.4)B [0,0.2)VB Prob. Distribution Discrete Set {VB,B,N,G,VG} Real [0,1] Boolean {False,True} VBBNGVG VBBNGVGVBBNGVG falsetrue VBVG IIIA-CSIC

Conversion Uncertainty (CU) Uncertainty produced by conversion between representation types. To From BooleanDiscrete SetBounded RealProb. Dist. Boolean Discrete Set Bounded Real Prob. Dist0000 CU values Let X,Y be representation types, then the CU value associated to the conversion from type X to Y is defined as: CU(X,Y) = H(Y | X) (Conditional entropy) IIIA-CSIC

Input calls Output calls directExp(DExperience) comm(EvalBelief) getReputation(Entity)  Reputation getReputation(Entity,Focus)  Reputation getImage(Entity,Focus)  Image API Interface Implementation(1) Decision Making Module Communication Module CTR y API y API interface and agent architecture IIIA-CSIC

Implementation(2) API interface for Abdul-Rahman & Hailes Model Distributed Model Agents evaluate direct experiences with {VU,U,T,VT} Agents can receive recommendations (direct experiences) from others. The model returns a degree of trust of agent A in context C with the values {Very Trustworthy, Trustworthy, Untrustworthy, Very Untrustworthy } or with an uncertain value: U +, U 0, U - (between VT-T, T-U, U-VU) Comm(DExperience) directExp(DExperience) getImage(Entity, Focus)  Image Evaluation: discrete sets {VB,B,G,VG} VU UTVTU-U- U0U0 U+U+ Evaluation: probability distribution API Implementation IIIA-CSIC

Implementation(3) API interface for eBay Model Centralized Model Users evaluate their transactions sending to the system {+1,0,-1} The reputation of a concrete user is a number between 0 and , represented by a system of colored stars. API Implementation Comm(DExperience) getReputation(simpleAgent)  Reputation Evaluation: discrete sets VB 0N +1VG Evaluation: bounded real IIIA-CSIC

Using reputation in e-institutions IIIA-CSIC Integration of reputation mechanisms in the eI. Integration of a cognitive agent architecture in the context of an eI. Specification and implementation of a common ontology for reputation. Human interface with the eI.

IIIA-CSIC