Explaining Cognitive Assistants that Learn

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Explaining Cognitive Assistants that Learn

• Deborah McGuinness1, Alyssa Glass1,2, Michael
  Wolverton2
• 1Knowledge Systems, AI Laboratory
• Stanford University
• dlm glass _at_ksl.stanford.edu
• 1SRI International
• mjw_at_ai.sri.com
• thanks to Paulo Pinheiro da Silva, Li Ding,
  Cynthia Chang, Honglei Zeng, Vasco Furtado, Jim
  Blythe, Karen Myers, Ken Conley, David Morley

2
General Motivation
Provide interoperable knowledge provenance
infrastructure that supports explanations of
sources, assumptions, learned information, and
answers as an enabler for trust.

• Interoperability as systems use varied sources
  and multiple information manipulation engines,
  they benefit more from encodings that are
  shareable interoperable
• Provenance if users (humans and agents) are to
  use and integrate data from unknown, unreliable,
  or evolving sources, they need provenance
  metadata for evaluation
• Explanation/Justification if information has
  been manipulated (i.e., by sound deduction or by
  heuristic processes), information manipulation
  trace information should be available
• Trust if some sources are more trustworthy than
  others, representations should be available to
  encode, propagate, combine, and (appropriately)
  display trust values

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Inference Web Infrastructure primary
collaborators Ding, Chang, Pinheiro da Silva,
Zeng, Fikes

• Framework for explaining question answering tasks
  by
• abstracting, storing, exchanging,
• combining, annotating, filtering, segmenting,
• comparing, and rendering proofs and proof
  fragments
• provided by question answerers.

4
ICEE Integrated Cognitive Explanation
Environment

• Improve Trust in Cognitive Assistants that learn
  by providing transparency concerning   
  provenance    information manipulation   
  task processing    learning

5
ICEE Architecture
Collaboration Agent
Task Manager (TM)
Explanation Dispatcher
TM Wrapper
TM Explainer
Justification Generator
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During the demo, notice

• User can ask questions at any time
• Reponses are context-sensitive
• Dependant on current task processing state and on
  provenance of underlying process
• Explanations generated completely automatically
• No additional work required by user to supply
  information
• Follow-up questions provide additional detail at
  users discretion
• Avoids needless distraction

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• Example Usage
• Video Clip

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Task Explanation

• Ability to ask why at any point
• Context appropriate follow-up questions are
  presented

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Explainer Strategy (for cognitive assistants)

• Present
• Query
• Answer
• Abstraction of justification (using PML
  encodings)
• Provide access to meta information
• Suggests drill down options (also provides
  feedback options)

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Sample Introspective Predicates Provenance

• Author
• Modifications
• Algorithm
• Addition date/time
• Data used
• Collection time span for data
• Author comment
• Delta from previous version
• Link to original

Glass, A., and McGuinness, D.L. 2006.
Introspective Predicates for Explaining Task
Execution in CALO. Technical Report, KSL-06-04,
Knowledge Systems Lab., Stanford Univ.
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Task Action Schema

• Wrapper extracts portions of task intention
  structure through introspective predicates
• Store extracted information in action schema
• Designed to achieve three criteria
• Salience
• Reusability
• Generality

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SupportsTopLevelGoal(x) IntentionPreconditionMet
(x) TerminationConditionNotMet(x) gt
Executing(x)
TopLevelGoal(y) Supports(x,y) gt
SupportsTopLevelGoal(x)
ParentOf (x,y) Supports(y,z) gt Supports (x,z)
ParentOf (x,y) Supports(y,z) gt Supports (x,z)
GS GetSignature BL BuyLaptop GA GetApproval
Supports (x,x)
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User Trust Study

• Interviewed 10 Critical Learning Period (CLP)
  participants
• Programmers, researchers, administrators
• Focus of study
• Trust
• Failures, surprises, and other sources of
  confusion
• Desired questions to ask CALO
• Initial results
• Explanations are required in order to trust
  agents that learn
• To build trust, users want transparency and
  provenance
• Identified question types most important to CALO
  users --gt motivation for future work

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Future Directions

• We will leverage results from our trust study to
  focus and prioritize our strategies explaining
  cognitive assistants e.g., learning specific
  provenance
• We will expand our explanations of learning to
  augment learning by instruction and design and
  implement explanation of learning by
  demonstration (initially focusing on LAPDOG).
• We will expand our initial design of explaining
  preferences in PTIME
• Write up and distribute user trust study to CALO
  participants
• Consider using conflicts to drive learning and
  explanations I have not finished because x
  has not completed.
• Advanced dialogues exploiting TOWEL and other
  CALO components
• Potentially exploit our work on IW Trust - a
  method for representing, propagating, and
  presenting trust within the CALO setting
  already have results in intelligence analyst
  tools, integration with text analytics,
  Wikipedia, likely to be used in IL, etc.

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Explaining Learning by Demonstration

• General Motivation
• LAPDOG (Learning Assistant Procedures from
  Demonstration, Observation, and Generalization)
  generalizes the users demonstration to learn a
  procedure
• While LAPDOGs generalization process is designed
  to produce reasonable procedures, it will
  occasionally get it wrong
• Specifically, it will occasionally over
  generalize
• Generalize the wrong variables, or too many
  variables
• Produce too general a procedure because of a
  coarse-grained type hierarchy
• ICEE needs to explain the relevant aspects of the
  generalization process in a user-friendly format
• To help the user identify and correct over
  generalizations
• To help the user understand and trust the learned
  procedures
• Specific elements of LAPDOG reasoning to explain
• Ontology-Based Parameter Generalization
• The variables (elements of the users
  demonstration) that LAPDOG chooses to generalize
• The type hierarchy on which the generalization is
  based
• Procedure Completion
• The knowledge-producing actions that were added
  to the demonstration
• The generalization done on those actions
• Background knowledge that biases the learning
• E.g., rich information about the email, calendar
  events, files, web pages, and other objects upon
  which it executes it actions
• Primarily for future versions of LAPDOG

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Explaining Preferences

• General Motivation
• PLIANT (Preference Learning through Interactive
  Advisable Non-intrusive Training) uses
  user-elicited preferences and past choices to
  learn user scheduling preferences for PTIME,
  using a Support Vector Machine.
• Inconsistent user preferences, over-constrained
  schedules, and necessity of exploring the
  preference space result in user confusion about
  why a schedule is being presented.
• Lack of user understanding of PLIANTs updates
  creates confusion, mistrust, and the appearance
  that preferences are being ignored.
• ICEE needs to provide justifications of PLIANTs
  schedule suggestions, in a user-friendly format,
  without requiring the user to understand SVM
  learning.
• Providing Transparency into Preference Learning
• Augment PLIANT to gather additional
  meta-information about the SVM itself
• Support vectors identified by SVM
• Support vectors nearest to the query point
• Margin to the query point
• Average margin over all data points
• Non-support vectors nearest to the query point
• Kernel transformation used, if any
• Represent SVM learning and meta-information as
  justification in PML, using added SVM rules
• Design abstraction strategies for presenting
  justification to user as a similarity-based
  explanation

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Advantages to ICEE Approach

• Unified framework for explaining task execution
  and deductive reasoning.
• Architecture for reuse among many task execution
  systems.
• Introspective predicates and software wrapper
  that extract explanation-relevant information
  from task reasoner.
• Reusable action schema for representing task
  reasoning.
• A version of Inference Web for generating formal
  justifications.

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Resources

• Overview of ICEE
• McGuinness, D.L., Glass, A., Wolverton, M., and
  Pinheiro da Silva, P. Explaining Task Processing
  in Cognitive Assistants that Learn. AAAI 2007
  Spring Symposium on Interaction Challenges for
  Intelligent Assistants (to appear). (Updated
  version will be in FLAIRS 2007).
• Introspective predicates
• Glass, A., and McGuinness, D.L. Introspective
  Predicates for Explaining Task Execution in CALO.
  Technical Report, KSL-06-04, Knowledge Systems,
  AI Lab., Stanford University, 2006.
• Video demonstration of ICEE
• http//iw.stanford.edu/2006/10/ICEE.640.mov
• Explanation interfaces
• McGuinness, D.L., Ding, L., Glass, A., Chang, C.,
  Zeng, H., and Furtado, V. Explanation Interfaces
  for the Semantic Web Issues and Models. 3rd
  International Semantic Web User Interaction
  Workshop (SWUI06). Co-located with the
  International Semantic Web Conference, Athens,
  Georgia, 2006.
• Inference Web (including above publications)
• http//iw.stanford.edu/

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Extra

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How PML Works
isQueryFor
IWBase
Query fooquery1 ltformal internal
structured querygt
Question fooquestion1 ltInput language
questiongt
hasAnswer
Justification Trace
hasLanguage
NodeSet foons1 (hasConclusion )
Language
hasInferencEngine
fromQuery
isConsequentOf
InferenceEngine
hasRule
InferenceStep
InferenceRule
hasAntecendent
Source
NodeSet foons2 (hasConclusion )

hasVariableMapping
Mapping
isConsequentOf
fromAnswer
hasSourceUsage
hasSource
SourceUsage
InferenceStep
usageTime
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Sample Task HierarchyPurchase equipment

• Purchase equipment
• Collect requirements
• Get quotes
• Do research
• Choose set of quotes
• Pick single item
• Get approval
• Place order

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Sample Task HierarchyGet travel authorization

• Get travel authorization
• Collect requirements
• Get approval, if necessary
• Note this conditional step was added to the
  original procedure through learning by
  instruction
• Submit travel paperwork

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PML in Swoop
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Explaining Extracted Entities
Source fbi_01.txt Source Usage span from 01 to
78
Same conclusion from multiple extractors
conflicting conclusion from one extractor
This extractor decided that Person_fbi-01.txt_46
is a Person and not Occupation
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Task Management Framework


Activity Recognizer
Advice
Preferences
Advice
Preferences
Preferences
Time
Time
Task
Task
Manager
Manager
Manager
Manager
Location Estimator
PTIME
PTIME
SPARK
SPARK
Process Models
Process Models
Procedure
Execution Monitor
Execution Monitor
Task Explainer
Task Explainer
Learners
Predictor
Predictor
ICEE
ICEE
Tailor, LAPDOG, PrimTL, PLOW
ProPL
ProPL