designing organizations with opera - universiteit utrecht · 2010. 8. 26. · designing opera...
TRANSCRIPT
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Designing Organizations with OperA
Virginia Dignum Delft University of Technology
Huib Aldewereld Utrecht University
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Agenda
• Introduction • OperA Model
– Organizational Model – Social Model – Interaction Model
• Design Exercise – Scenario: Conference
• Discussion
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Modeling organizations
• Organizational structure: – Structure is what persists when components or
individuals enter or leave an organization. (Ferber, 2003)
• Organizational dynamics: – Participating entities change, environment change
• Organizational strategy – What does the organization want? – And how does the organization want to achieve it?
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Components of organizations
• Entities (roles, positions, people, groups, components, …) • Relationships (networks, interactions, coordination …) • Goals (purpose, intention, shared, …) • Norms (culture, rules, …) • Environment (physical, social, open, dynamic, restrictive…)
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Characteristics of entities
• The entities to be organized are heterogeneous • The entities to be organized are expected to be rational,
cognitive – (Olmstead, 2002): The people in this definition are
physical organisms and psychological processes [...] [whose] influence is a function of both his or her psychological properties and the properties of the coordination and decision making roles assigned to him or her.
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Characteristics of relationships
• The organization should create order among entities. • Relationships result in more than the individuals
– (Morin 1977): Endowed with qualities not apprehended at the level of the components or individuals.
• The organization is responsible for the achievement of the overall goal of the system.
• The organization should create a coherence of the whole.
• Possible relations between entities are: – Delegation of tasks – Transfer of information – Obligation and norms – Synchronization of actions – Responsibility between agents – Access to resources and services
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Characteristics of goals
• Organizational goals are not necessarily goals of any of the individuals
• Combined activity is needed to achieve organizational goals • Global strategy but local decision
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Characteristics of norms
• Describe desired organizational states • Norms as Constraints
– Cannot be violated: guaranteed fulfillment • Norms as Regulations
– Can be violated: agent decides • Balance between CONTROL and EFFICIENCY
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Characteristics of environment
• Organizations need to perceive, reason, and act in relation to the surrounding environment
• Contingent: – match among (business) strategy, organizational
structure, and the characteristics of the environment is necessary for high performance
• Dynamic: – Agents can migrate, behavior can evolve. – organizational structures change, disappear or grow – organizational objectives change
• Open: – Distributed management, knowledge and data – Components are not controlled by one entity
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OPERA
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OperA Model
• Organizational Model – represents organizational aims and requirements – roles, interaction structures, scene scripts, norms
• Social Model – represents agreements concerning participation of
individual agents (‘job’ contracts for agents) – rea = role enacting agent
• Interaction Model – represents agreements concerning interaction between
the agents themselves (‘trade’ contracts between reas)
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Organizational Model
• Social Structure – roles, groups, dependencies
• Interaction Structure – scene scripts, connections, transitions
• Normative Structure – role, scene and transition norms
• Communication Structure – communicative acts, domain ontology
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Social Model
• Role negotiation scenes • Individual agents have own goals and requirements, that
not necessarily meet role specification • Social Contract
– describes a specific agreement for a role enacting agent (rea)
– Meets organizational expectations – Incorporates individual behavior
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Interaction Model
• Script negotiation scenes • Interaction contract
– describes a specific performance of a scene • Scene Instantiation
– Reas are not exactly as the role descriptions – Describe the specific interaction protocol realizing
landmarks and incorporating rea capabilities
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OperA
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Organizational Model Social Model
Social commitment
Interaction Model
Interaction commitment
role
interaction pattern
agent
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Designing OperA models
• Organizational goals imply different requirements concerning coordination
• Analysis and facilitation of social context – Organizational Model – Flexible structures: landmarks
• Analysis and facilitation of individual context – Social model: instantiation to individual requirements – Interaction model: protocols
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Example: Conference organization
• Objective: – Realize a scientific conference
• Organizational requirements – Separation of duties between program and local organization – Ensure scientific quality – Ensure large attendance – …
• Agent requirements – Present own research – Receive information about new research development – Network – …
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Designing the Coordination
• Organization – Global objectives and requirements
• Functional (what) • Interaction (how)
– Objective decomposition (to roles)
• Stakeholders – Objectives – Dependencies – Requirements – Role tables: relation to stakeholders
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Role Relation to society Objectives Dependencies
Role 1 Stakeholder X … Role N
Role M From coordination model … Role P, Role 1
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Scenario: Conference organization • Modeling the organization of a conference
• Stakeholders • Objectives • Dependencies
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Role Objectives Dependencies
Author Paper accepted Program chair
Local organizer Successful conference Program chair, Participants…
Program chair High quality conference Authors, reviewers
Reviewers Quality papers, independent evaluation
Program chair
…
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Designing the (Institutional) Environment • Identify organizational norms
– Responsibility analysis – Resource analysis – Trigger analysis – Norm specification – Sanction specification
• Norm tables
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Description Norm Analysis
Type (O, F, P)
Textual description
Responsibilities Initiator: role Action: role
Triggers Pre condition: state Post condition: state
Specification whenever state then role is O,F,P to achieve state otherwise sanction
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Norms
• Statutes: Abstract norms – Main objective of the organization, – Values that direct the fulfilling of this objective – Context – E.g. Fairness of exchange
• Concrete norms – Protocols and Rules : enable agents to comply with
organizational norms – Constraints: cannot be violated – Regulations: agent can decide
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Communication Dimension
• Abstract Level – Generic Terms
• Incontextual concepts – Model Ontology
• concepts of the framework itself • E.g. norm, rule, role, group, violation, landmark…
• Concrete Level – Concrete domain ontology – Generic communication acts
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Scenario: ontology and norms
• Ontology for the conference organization – Author, paper, session, review, PC-member, website,
deadline, notification, proceedings, …
• Norms in the conference organization – Role: PC member cannot review own papers – Interaction: Session chair can stop presentation if too
long – Global: English language must be used for all
communication
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• Social Structure – Roles – Sub-objectives are identified by means-ends analysis – Role dependencies identify interaction between roles ->
scenes
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ROLE DEFINITION Role id Identified in Environment Level Objectives Formalization of objectives identified in the role table Sub-objectives Result of means-end analysis for each role objective Rights From means-end analysis and norm analysis Norms From the Norm analysis in Environment Level Type Roles associated with the coordination model are
institutional, and operational roles are in principle external.
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Social Structure
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Role example
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Designing the Behavior
• Interaction Structure – Scene scripts – Interaction structure
• Partial ordering of scenes • Relationships between scenes
– Causal dependency: Sequence of scenes – Synchronization: AND relation between scenes – Parallelism: OR relation between scenes – Instantiation: new scene instances
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Scene script
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SCENE DEFINITION Scene identifier
From role dependency
Roles Participants in scene
Description Textual description
Results Objectives of scene -> relate to role dependency
Patterns Partial ordering of landmarks to achive result, for each scene result
Norms From norm analysis
Rationale Further information
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Scene example
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Interaction Structure
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Scenario: verification
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Further: Social and Interaction Model • Specification of role negotiation scenes • Specification of negotiator agent
• Based on the role descriptions specified in the OM – minimum requirements – negotiable characteristics, and their range
Role Negotiation Scene: Role R Roles Negotiator (N), applicant (A)
Results ρ = contract(A, R, SocialContract)
Plans Πρ = { agreed(char1) AND ... AND agreed(charN) BEFORE contract-agreed(N, A, social-contract(A, R, CC)) }
Norms PERMITTED(N, negotiate-social-contract(A, R) ). OBLIGED (N, propose-range(char1, min, MAX))...
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Roles vs. agents
• Role – Abstract representation of a function, service or
identification within a group/society – Desired activity and behavior, from society perspective
• Agent – is capable of flexible, autonomous action in order to
meet its design objectives. – Agents act, roles not
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Example rules(mary) = {supervise(s) read(p)}
rules(PC-member) = {review(p) send-cfp}
review(p) ⇒ read(p)
selfish PC(mary): supervise(s); review(p); advertise-conference
social PC(mary): review(p); advertise-conference; supervise(s)
max social PC(mary): review(p); advertise-conference
mary PC-member
PC (mary)
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Social Model
• Based on role negotiation scenes • Depending on the characteristics of the agents that apply
for society roles • Results in:
– Role enacting agent – Enactment contract
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Social Contract
Agent Anne
Role Knowledge seeker
Clauses
1. PERMITTED( Anne, access-kb([KB1, KB3, KB7]) 2. OBLIGED(Anne, publish-received-knowledge(item, KB3) | allows(KO, publish)) 3. ∀p: contract(p, Anne) → PERMITTED(p, publish(p, Anne’s-item, kb))
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SM Design Steps • For external roles:
– Identify minimum requirements – Identify negotiable characteristics, and their range
• Specify role enactment scripts – Negotiator (internal) agent – Negotiation pattern for role characteristics
• Results in role enacting agent design and contract
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Example: • Reviewer agent:
• Minimum reqs: provide areas of interest, …
• Negotiable: number papers, deadline,…
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Interaction model
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• Based on script interaction scenes • Depending on the characteristics of the agents that
apply for society roles • Results in
– Specific protocols for the scenes, that are supported by the agents
Interaction Scene: PC-member role enactment
Roles Society keeper (SK), applicant (A), society register (R)
Results ρ = contract(A, PCmember, SocialContract)
Plans Πρ = {agreed(max-papers(M)) AND agreed(review-deadline(D)) BEFORE
contract-agreed(SK, A, social-contract(A, PCmember, CC)) BEFORE
contract-registered(R, social-contract(A, PCmember, CC)) }
Norms PERMITTED(SK, negotiate-social-contract(A, PCmember) ).
OBLIGED (SK, role-description-announced(role(PCmember)).
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IM Design Steps • For each scene:
– Identify negotiable landmark range
• Specify script negotiation scripts – Negotiator (internal) agent – Negotiation pattern for landmarks – Other protocol requirements
• Results in interaction protocols and contracts
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Example: • Review scene:
• Fixed Landmarks: papers send to reviewer, review received
• Negotiable: review deadline, reminder, …
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Conclusions
• Organization is a complex and rich dimension in MAS: – represented in different ‘‘eyes’’: Designer – Observer – Agents, – expressed with two points of view: Agent-Centered vs.
Organization-Centered, – using multiple models: e.g. Joint intentions, shared plans,
dependence theory, … • Organization is built to fulfill different aims
– To help the cooperation between the agents, – To control the cooperation between the agents
• Accounting or not for the autonomy of the agents. • Multiple ways of Modeling and Programming Organizations
– Within Agents, – Within the system itself (e.g. Organization services), – Both in the Agents and in the System.
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Conclusions
• Organizing is a complex process: – Bottom up or top down, – Used in different contexts and applications:
• knowledge exchange, • Simulation, coordination.
• Reorganizing is a dynamic process: – Multiple dimensions (who, when, what, why) – Multiple styles – that could be predefined using an organizational
language (same or different form of the domain level)
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Literature / More information
• OperA – Virginia Dignum: A Model for Organizational Interaction:
Based on Agents, Founded in Logic, 2004 – My Webpage: http://www.cs.uu.nl/~virginia
• OperettA tool – Virginia Dignum and Huib Aldewereld: OperettA:
Organization-Oriented Development Environment, LADS@MALLOW, 2010.
– http://www.cs.uu.nl/research/projects/opera/
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