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_at_bbn.com

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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?

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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 agents 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)

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A Simple Example

• 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?

Dispatcher

x
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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.)

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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.

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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.

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Dynamic Information Sharing

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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.

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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.