ESAW 2004 Extending Electronic Institutions: An Explorer’s Log Pablo Noriega IIIA-CSIC Barcelona

EUMAS 04 Barcelona December 16,17 REGISTER SOON

ESAW 04 3 Goals of this Talk Present the underlying intuitions of our proposals Share our present cogitations Invite you to participate

ESAW 04 4 EI gang at IIIA-CSIC Currently: Josep Lluis Arcos * Eva Bou * Guifre Cuni * Andres Garcia Pere Garcia * Andrea Giovanucci * Carlos Hernandez Pablo Noriega Juan Antonio Rodriguez Aguilar Marco Schloemerer Carles Sierra Formerly: Mark Esteva Jordi Sabater

ESAW 04 5 EI -Influencias Dialogues Economics Norms Coordination MASMAS

ESAW 04 6 “Institution: collection of artificial constraints that regulate agent interactions” A.D. North

ESAW 04 7 EI and ordinary institutions Fix meaning Clarify expectations on the behavior of others Implement due process Interface: Individual rationality and social outcomes Purpose: reduce uncertainty

ESAW 04 8 EI : alternative views EIs as Dialogues: Dialogical language Types of dialogue (protocol, point of conversation) Changes of conversation Obligations EIs as Norms Logical theories Context Compliance / enforcement EIs as Interface: Coordination artifact Interaction-centered problem solving Success / failure Computational Environments Applications Social Perspective

ESAW 04 9 Adscription

ESAW A-open MAS Adscription-open System Definition: An Adscription-open System is a distributed system involving autonomous, independent entities that are willing to conform to a shared set of interaction conventions

ESAW A-open MAS: H 0 Participants are commitment-making agents All interactions are construable as speech acts Interactions are repetitive Interactions produce social commitments

ESAW EI = I(H 0 ) Dialogical Framework: Linguistic and social structure to give meaning to agent interactions. Performative Structure: scenes and relationships between scenes (navigation, precedence, causality) Rules: Role-dependent conventions to establish social commitments

ESAW Electronic Institution Components PERFORMATIVE STRUCTURE (NETWORK OF PROTOCOLS) SCENE (MULTI-AGENT PROTOCOL) AGENT ROLES Buyers’ Payment NORMS

ESAW Simple Electronic Institutions: EI 0 = I 0 (I(H 0 )) Dialogical Framework: Linguistic and social structure to give meaning to agent interactions. Performative Structure: scenes and relationships between scenes (navigation, precedence, causality) Rules: Role-dependent conventions to establish social commitments DF = S = PS = (  n j =1 uttered(s j,w kj,i lj )   m k =1 e k )  (  n’ j =1 uttered(s’ j,w’ kj,i’ lj )   m’ k = 0 e’ k )

ESAW EI 0 : Dialogical Framework We define a dialogical framework as a tuple DF = where: O stands for the institutional ontology; I is the set of illocutionary particles; L stands for a representation language; R I is the set of internal roles; R E is the set of external roles; and R S is the list of relationships over roles; Illocution: i ( , ,  ) Declare (auct,all, offer(good,price), t)

ESAW Performative Structure Complex activities can be specified by establishing relationships among scenes that: capture causal dependency. define synchronisation mechanisms. establish parallelism mechanisms. define choice points that allow roles leaving a scene to choose which activity to engage in next. establish the role flow policy.

ESAW Sellers’ admission Buyers’ admission FM Scenes Bidding Sellers’ settlements Buyers’ settlements & Delivery Buyers Sellers

ESAW EI 0 : Performative Structure A performative structure is a tuple PS = where: S is a finite, non-empty set of scenes; T is a finite and non-empty set of transitions; s 0  S is the root scene; s   S is the output scene; E = E I  E O is a set of arc identifiers where E I  S x T is a set of edges from scenes to transitions and E O  T x S is a set of edges from transitions to scenes; f L : E  2 VA x R is the labelling function; f T : T  {AND-AND,AND-OR,OR-OR,OR-AND} maps each transition to its type; f E O : E O  E maps each arc to its type; C: E I  CONS maps each arc to a boolean expression representing the arc's constraints.  : S  {0,1} sets if a scene can be multiply instantiated at execution time

ESAW FM Performative Structure (ISLANDER)

ESAW Scene A scene is a pattern of multi-agent conversation. A scene is specified by a finite state oriented graph where the nodes represent the different states and oriented arcs are labelled with illocution schemes or timeouts. During the enactment new agents can join the scene or some of the participants can leave the scene at definite states depending on their role. A scene may have multiple (simultaneous) instantiations, and be enacted by different groups of agents.

ESAW Voice Bidding

ESAW EI 0 : Scene Formally, a scene is a tuple: S = where: R is the set of roles of the scene; DF is a dialogical framework; W is a finite, non-empty set of scene states; w 0  W is the initial state; W f  W is the non-empty set of final states; (WA r ) r  R  W is a family of non-empty sets such that WA r stands for the set of access states for the role r  R; (WE r ) r  R  W is a family of non-empty sets such that WE r stands for the set of exit states for the role r  R;   W x W is a set of directed edges; :   L is a labelling function; min,Max: R  N min(r) and Max(r) return respectively the minimum and maximum number of agents that must and can play the role r  R

ESAW Norms Social Committments Illocutionary meaning Individual Navigation

ESAW EI 0 : Norms Individual behavior rules define the conditions for an agent to take an action and the effects of taking such actions within the institution. Conditions: Current state of the scene (conversation) Role played by speaker and hearers of a given illocution Prevailing state of social commitments Effects: Changes in the state of a conversation and social commitments Obligations imposed to agents. Trajectories that agents can follow. Example A buyer winning a bidding round is required to proceed to the buyers settlement scene to pay for the good.

ESAW FM: Individual Behavior Rules

ESAW EI 0 Norm Enforcement device: Governor Agent whose purpose is to mediate between the institution and participating agents. Each external agent is attached to a governor that sees to it that the agent behaves according to the institutional conventions: IDENTITY NAVIGATION INFORMATION PASSING MESSAGES TIMING

ESAW EI : An Idealized Trajectory FM-TestBed FishMarket Auctions MASFIT FM EI EI 0 ISLANDER EIDE : ISLANDER Simdei AMELI Abuilder SADDE EIDE : ISLANDER Simdei AMELI Abuilder

ESAW EI 0 : Tools

ESAW EI : Potential Development EI EI 0 Theory Methodology Applications Tools EI plus

ESAW EI 0 : Cogitations We have taken a strong “dialogical stance” We have also dealt with static scene definitions We have taken a “policing” approach to norm compliance, and norm enforcement (so far). Integrated framework: representation / methodology / tools Unified metaphor from Design to deployment Applicable Extend to dynamic protocols and less structured interactions. other normative conceptions complex regulated social environments

ESAW EI : Extensions EI EI 0 Theory Methodology Applications Tools EI plus STRUCTURAL EXTENSIONS NORMATIVE EXTENSIONS META INSTITUTIONAL EXTENSIONS

ESAW EI : Structural Extensions (1) DB UB CB Vickrey Auction PS Scene Interchange

ESAW EI : Structural Extensions (2) UB CB PS Splicing

ESAW Splicing Splicing Techniques Clipping Chopping Interleaving Growing Nesting Splicing Algebra ? atomic operations separability, correctness, commitment consistency, …

ESAW Revising Scenes Scenes as Functors auction ( ; ) Scenes as Goals Price-fixing  {fixed,auction,clearing,negotiation} PS as Problem Decomposition AuctHouse:=registration + adminsion + price-fixing + settlements

ESAW Structural Extensions: Taxonomy ScenePS Fixed with flexible parametersFixed STATICSTATIC FLEXIBLEFLEXIBLE Interchangeable from set of available fixed scenes Fixed DYNAMICDYNAMIC Interchangeable from set of Available fixed PSs Flexible Assemblable from available subPSc OPENOPEN Dialogical Patterns

Ag 1 Ag 2 Ag n Destination Data I Ir 12 I I INPUT Output Competivness Positioning Susteinability Profit Scenarios r 2n r 1n I = Institution Ag n = Agent “n” r i n = Relationship Ag i y Ag n Touring Machine

ESAW EI : Meta-institutional Environments $ ? Contr

ESAW EI : Other Extensions EI envr EI EI 0 EI 1 Theory Methodology Tools EI 2 EI  From “buildings” to “urbanism”

ESAW Other Extensions: Taxonomy (2) Promulgation External, Internal Compliance Obligatory Facultative Enforcement Strict Sanctions Self-enforced

ESAW Id PromulgationPS StructureComplianceEnforcement EI 0 ExternalFixedObligatoryStrict e-commerce EI n ExternalFlexibleFacultativeSanctions e-government procedures External & internal EvolvingFacultativeIncentives Complaints, conflict resolution EI  InternalFlexibleObligatorySelf Parlamentary Procedures EI env External / internalFlexibleFacultativeIncentives Tourism Destination Supply Network Extensions: Application Domain Examples

ESAW EI Extensions Applications EI 0 e-commerce EI n Due process EI  Adscription open interactions EI env ( Meta Institutional Environments ) Supply networks Localities Tools e 0 ISLANDER, AMELIE,… e n ISLANDER+, AMELIE+,… e  ISLANDER*,AMELI*… Engineering Environments

ESAW Ongoing Work

ESAW Ongoing Work FREE CD and Demo

QUESTIONS ?

ESAW FIN

ESAW BACKUP SLIDES Juan Antonio Rodriguez, Marc Esteva, Josep Lluis Arcos, Et.al.

ESAW EI adscription-open MAS

ESAW EI adscription-open MAS

ESAW 04 50

ESAW Electronic Institution Infrastructure

ESAW AMELI functionalities MEDIATION To facilitate agent communication within conversations (scenes). COORDINATION AND ENFORCEMENT To guarantee the correct evolution of each conversation (preventing errors made by the participating agents by filtering erroneous illocutions, thus protecting the institution). To guarantee that agents ’ movements between scenes comply with the specification. To control which obligations participating agents acquire and fulfil. INFORMATION MANAGEMENT To facilitate participating agents the information they need to participate in the institution.

ESAW AMELI architecture INSTITUTION MANAGER SCENE MANAGERS TRANSITION MANAGERS GOVERNORS

ESAW Governor Mediates between institution and participating agent. Controls that an agent behaves according to the institution specification (rules).

ESAW AMELI implementation features Agent-based Realised as a middleware layer Architecturally neutral General purpose (can interpret any institution specification) Communication neutral Scalable (it can be distributed among several machines)

ESAW Operations

ESAW Operations

ESAW Operations

ESAW Operations

ESAW Operations

ESAW Conclusions Engineering open multi-agent systems is a highly complex task. Electronic institutions reduce this complexity by introducing regulatory environments. We have presented AMELI, a social middleware that facilitates the deployment of electronic institutions. Given any institution specification, our social middleware is capable of enforcing the institutional rules. The combination of ISLANDER and AMELI targeted at supporting environment engineering in open multi-agent systems.

ESAW Transition Management Movements are done asynchronously. For movements to current scene executions the transition informs the scene managers. For movements to new scene execution the transition manager informs the institution manager, which creates a scene manager for it.

ESAW Transition management Each transition is managed by a transition manager. Agents within a transition can ask for target scenes to join. The transition manager is in charge of controlling when the transition can be fired (agents can move).

ESAW Norm Management Java Expert System Shell (JESS) to manage norms. A governor has one thread devoted to manage its connection to JESS. For each norm N i, this thread adds the corresponding R1 i into the JESS rule base. Later on this thread adds the illocutions (appearing on the norms) as the facts of the system. JESS informs the thread whenever a rule is fired.

ESAW Norm management Norms managed as a rule-based system. Constructed from an ISLANDER specification. The facts are illocutions uttered by agents. Each governor manages his agent’s obligations.

ESAW Norm Management A norm N i : is transformed into: Antecedent Defeasible Antecedent Obligations Norm Activation Obligations fulfilment

ESAW Agent to Governor Messages

ESAW Governor to Agent Messages

ESAW Electronic Institution Specification with ISLANDER Common Ontology and language Agent Roles Multi-agent protocols Network of protocols Norms

ESAW Institution Execution Electronic institutions will be populated at execution time by heterogenous and self-interested agents. The institution execution can be regarded as the execution of its different scenes. Agents devote their time: interacting with other agents in the different scene executions moving among them. As a consequence agents acquire and fulfill obligations.

ESAW Institution execution

ESAW Institution execution

ESAW Institution execution

ESAW Approach ENVIRONMEN T ELECTRONIC INSTITUTION NORMS AGENT 1 AGENT 2 AGENT 3 AGENT 1 AGENT 2 AGENT 3  EXECUTION STATE: 

ESAW Approach ENVIRONMEN T ELECTRONIC INSTITUTION NORMS AGENT 1 AGENT 2 AGENT 3 AGENT 1 AGENT 2 AGENT 3  Action Correct? EXECUTION STATE: 

ESAW Approach ENVIRONMEN T ELECTRONIC INSTITUTION NORMS AGENT 1 AGENT 2 AGENT 3 AGENT 1 AGENT 2 AGENT 3 ’’ EXECUTION STATE:  →  ’

ESAW Execution State  = stands for an institution execution state where: Ag = {ag 1,..., ag n } is a finite set of participating agents.  = {  i k | s i  S, k  N} is the set of all scene executions. T = {T 1,..., T n } stands for all transition executions. Obl {obl 1,..., obl n } is the set of agents’ pending obligations.  i k = { , , A} stands for scene execution state where:  represents the scene’s current state.  = {  1,...,  n } stands for the context (bindings) produced by illocutions. A = {(ag,r) | ag  Ag, r  R} is the set participating agents along with their roles. Each transition execution state T i = { (ag,  ) | ag  Ag,  = { (  i k, r) |  i k  , r  R}} contains agents’ target scenes.