I-X Approach: Task-Directed Communication for Artifact Synthesis

1. I-X Austin Tate, Jeff Dalton, Robert Inder, John Levine, Robert Rae, Jussi Stader Artificial Intelligence Applications Institute Division of Informatics University of Edinburgh http://www.aiai.ed.ac.uk/project/ix/

2. I-X Approach • The I-X approach involves the use of shared models for task directed communication between human and computer agents who are jointly exploring (via some process(es)) a range of alternative options for the synthesis of an artifact such as a design or a plan (termed a product). • I-X system or agent has two cycles: • Handle Issues • Respect Domain Constraints • I-X system or agent carries out a (perhaps dynamically determined) process which leads to the production of (one or more alternative options for) a synthesised artifact. • I-X system or agent views the synthesised artifact as being represented by a set of constraints on the space of all possible artifacts in the domain.

3. What does I-X Offer? • Outer level approach of handling issues and respecting constraints in the domain model gives an intelligible approach to what an I-X system or agent does. • Middle level provides a fractally composable cell which employs a model/viewer/controller systems integration approach. • Detailed level provides an approach which represents and reasons with constraints on the space of all possible artifacts, and allows for the provision of specialised solvers for some or all of these detailed constraints. • I-X makes contributions at level 1 and 3, and is compliant with other approaches at level 2.

4. What does I-X Stand For? • Intelligent – I-X supports the construction of intelligent systems and intelligent agents • Intelligible - I-X supports the construction of systems which are intelligible to their users and to other systems and agents. • Integrated – I-X is a systems integration architecture. • Issue-based – I-X is an issue-based and issue handling architecture.

5. Example I-X Scenarios • I-Plan Planning Agent • DERA Master Battle Planner Agent • Emergency and Unusual Procedures Assistant • Expository Scenarios • Meeting Room Booking Agent • Non-activity based, nodes are meetings • Interior Decoration Design Agent • No time points • PicoIX and I-Sim • For simple coding experiments and explanations • Car Design Example • To show both product constraint adding and activity inclusion approaches both are possible and it is a design decision which to use • Example that can use probabilities within Issue Handlers and/or Constraint Managers

6. Shared Product Model – using Constraints on the space of products (<I-N-CA>). Shared Task Model - Mixed initiative model of “mutually constraining the space of products”. Shared Space of Options – for the Product. Shared Model of Agent Capabilities - handlers for issues, functional capabilities and constraint managers. Shared Understanding of Authority - management of the authority to handle issues and act which may take into account options (Partially) Shared Models

7. Knowledge Acquisition User Communication Formal Analysis System Manipulation Uses of a Shared Model Intelligible Representation

8. Issues Issues or Implied Constraints I Node Constraints N Constraints Detailed Constraints CA Space of Legitimate Product Models <I-N-CA> Product Model Nodes C=Critical Constraints A=Auxiliary Constraints

9. Choose (IH) Do (IH) Propagate Constraints IH=Issue Handler (Agent Functional Capability) I-X and <I-N-CA> Product Model Issues Nodes Constraints

10. Generic and Activity Ontologies • Generic Ontology • Entities • Relationships • Issues • Constraints • Nodes • Node-Relatable Objects • Activity Specialisation • Entities • Relationships • Issues • Constraints • Activities • Time-points • Activity-Relatable Objects

11. <I-N-CA> Generic Ontology • Entities • Relationships • Issues • Constraints • Node Constraints • Critical Constraints • Auxiliary Constraints • Nodes • Node-Relatable Objects (NROs)

12. <I-N-OVA> Activity Ontology • Entities • Relationships • Issues • Constraints • Node Constraints • Include Node Constraints • Other Node Constraints • Critical Constraints • Critical Ordering Constraints • Critical Variable/Object Constraints • Auxiliary Constraints • Auxiliary Ordering Constraints • Auxiliary Variable/Object Constraints • World-State Constraints • Resource Constraints • Other Constraints • Activities • Time-points • Activity-Relatable Objects (AROs)

13. I-X Components Controller Issue Handlers Model Manager Product Model(s) < I - N - CA > Inter-agent messages Information from the environment User Input Inter-agent messages Information to the environment User Output I/O Handlers Events -> Issues Other Information Domain Model Constraint Managers

14. I-X Components – Level 2 Controller Issue Handlers Model Manager Product Model(s) < I - N - CA > Constraint Associator Inter-agent messages Information from the environment User Input Inter-agent messages Information to the environment User Output I/O Handlers Events -> Issues Other Information Viewers Domain Model Constraint Managers

15. Viewers Issue Handlers Constraint Managers Domain Model I-X Cell – Model/Viewer/Controller I/O Handlers Controller Model Manager

16. Viewers Issue Handlers Domain Information Constraint Managers I-X Cell – Plug-in Components I/O Handlers Controller Model Manager

17. I-X Constraint Managers Issue Handlers Optional Try add C and/or A constraint(s) -> yes/no/maybe Commit add C and/or A constraint(s) -> yes/no/maybe (I.H. must commit to at least one case of the maybe) Model Manager Constraint Associator Yes No Maybe* in terms of alternative sets of Issues and C Constraints to add Constraint Managers Domain Model Model(s) < I - N - CA > * Maybe = Provided That

18. Inter-agent Tasking Options Inter-agent Tasking Options Inter-agent Tasking Options and/or intra-agent alternatives Intra-agent Model Alternatives Intra-agent Model Alternatives I-X Options and Alternatives Inter-agent Tasking Options I/O Handlers “Current Model ” related to an Option Mapping table for Option name to option object and therefore to to current and other intra-agent Alternatives related to the option(s) Controller Issue Handlers Model Manager Constraint Associator Yes No Maybe Intra-agent Model Alternatives for current alternative model only Domain Model applies to all Options and Alternatives Domain Model Constraint Managers Model with Intra-agent Alternatives < I - N - CA > Each option has one “Current Model” associated with it

19. I-X Controller Controller Issue Handlers • Issue is handled by IH… • IH can terminate having indicated: • Okay and (if changed) current model to be associated with option • Okay with current and N-1 other inter-agent options and/or intra-agent alternatives • Failed Model Manager

20. Dealing with Probabilistic Uncertainty • I-X may be applied to build a system in which the world is probabilistically modelled. • This is allowed for at the heart of the design by letting constraint managers return issues as well as yes/no/maybe answers. • A Constraint Manager (or Issue Handler) can give a yes/no answer in definite cases, or may be the maybe answer to return an issue that the answers given are only probabilistically true to some level. • Higher level Issue Handlers or the agent tasking environment can then respond as appropriate to that issue which will be attached to the model.

21. User Input/Output Inter-agent messages Information from/to the environment Agent ACL Message I/O Other I/O to and from the Environment Viewers Example I/O Scenarios I/O Handlers

22. Example I/O Scenarios • Inter-agent messages • Robot effectors and sensors • Thermometer with preset min and max alarms • Continuous readout thermometer • Database access • Monitor output for continuous status updates and warning lights for specific events • User viewing agent process and model(s) • User controlling agent process and model development

23. Probing Questions for an I-X Design • What issues does the agent handle (Verb, NPs, Qualifiers)? • What are the principal entities in the model which the agent handles? • What constraints in the domain should the agent respect? • What types of options the agent can handle? • What sources of input and output can the agent handle? • How are events communicated to the agent? • How can a user interact with the agent? • What views can the agent present?

24. Probing Questions for an I-X Design Level 2 • Can each Issue Handler return just one answer, or more than one? Can it fail (return no answers)? • Can the various constraints identified by handled by one solver or are several specialised solvers preferable? • What answers can each constraint manager provide? • Yes/No • Yes/No and Maybe • Notes: • Maybe states the constraint is valid with respect to the current state of the model – provided that the system handles or satisfies at least one of the alternative sets of issues and constraints returned. • Any constraint returned in a maybe answer from a constraint manager is defined as a critical constraint. • Any other constraint is termed an auxiliary constraint.

25. 2 I -PE I -P Process Process Editor Panel Cooperation and Communication I-Plan I -PL Process Planning Librarian Aid Other Agents I-Technology I-View I-Face - User I-Face - Repository I-Face

26. I-X Continuing Discussion Topics • Constraint Associator/Manager/Checker interfaces • Viewers for agent process, options,and model (<I-N-CA>) • I/O interfaces for all types of I/O scenarios • Is environment/state model a separate thing to <I-N-CA> model or just a part of the CA elements for all possible models? • What about information sources used by components of the agent? • How fundamental is the nature of the “Include Node” constraint? (e.g., in the interior decoration design scenario). • Concept of Options needs refining.

27. Further Information • http://www.aiai.ed.ac.uk/project/ix/