Cooperative Information Sharing Among Mixed-Initiative Human/Agent Teams

1. Cooperative Information Sharing Among Mixed-Initiative Human/Agent Teams Mark H. Burstein and David E. Diller BBN Technologies 10 Moulton Street Cambridge, MA 02138 burstein, ddiller@bbn.com

2. The Problem • In mixed human/agent organizations, complex tasks are frequently distributed (by humans) across coordinated teams of actors. • Information gathered by one tasked agent may be needed by another • This may have been part of an explicit or implicit plan, or the information may have been acquired serendipitously during execution. • Must the user describe these dependencies as part of tasking the agents or can they find each other dynamically?

3. Sharing Plans/Goals vs. Information Needs • Previous approaches to this kinds of team coordination focused on sharing plans or intentions among team members, and reasoning primarily about whether an agent’s observations implied other agents goals had succeeded/failed (which it would tell them) • TEAMCORE (Tambe 97) • Shared Plans (Grosz and Kraus 96, 99) • Shared Intentions (Cohen, Levesque 91, 97)

4. A Simple Example Dispatcher • Dispatcher sends helicopter across town to survey site of an accident (x) • Simultaneously, sends an ambulance to treat wounded. • En route, helicopter sees that primary route for ambulance is blocked by traffic. • How does it decide to send that information to the ambulance without further direction from the dispatcher? + x

5. A Question of ‘Which/How much information?’ • Given that the tasks delegated to each agent are known (partially shared goals/plans), must still decide • Which information is helpful to the other agent for planning or during execution • What information does the other agent already have (or can observe). • Catch-22 is that the plans the agents generate can be impacted by the information to be (but as yet) provided by their teammates. (So they may not even know precisely what to ask for.)

6. Coordinating Future Information Sharing • Approach is to establish shared knowledge of future agent information needs/capabilities by “word of mouth” message dissemination. • Information Requirement (IR) announcements describe classes of information (query patterns)that an agent will require to plan or achieve an intention. • Information Provision (IP) announcements describe information that an agent has or anticipates being able to provide as a result of its intended future actions.

7. Coordinating Information Goals Related to Intentions • When a new intention (to act or plan) is formed by an agent: • Announce information needs (IR) to local teammates. • Announce expectations of future knowledge gained by observations made during the planned activity (IP) • If agent has a need and receives an IP, subscribe to the agent issuing the IP announcement. • If agent has information covered by an outstanding IR announcement or subscription, send the information.

8. Dispatcher Task: Perform Situation Assessment Task: Provide Medical Assistance Info-Required, Provided:Road Status, Damage Report(site) Info-Required:Road Status, # Wounded(site) Subscribe Dynamic Information Sharing +

9. Improved Robustness • IP/IR protocols go beyond publish/ subscribe in that expectations of future knowledge (based on intentions) is the basis for coordination • IP and IR announcements reduce the ‘cognitive load’ on agents to infer what information will be wanted or available from particular other agents. • ‘Information Brokers’ can be established dynamically using IP/IR protocols to act as information coordinators for specific team plans.

10. For more information… Burstein, M.H. and Diller, D. E., “A Framework for Dynamic Information Flow in Mixed-Initiative Human/Agent Organizations.” To appear in Applied Intelligence, 2003. This work supported by DARPA contracts in the Control of Agent-based Systems (CoABS) and Mixed-Initiative Control of Automateams (MICA) programs.