Towards A Context-Based Dialog Management Layer for Expert Systems Victor Hung, Avelino Gonzalez & Ronald DeMara Intelligent Systems Laboratory University of Central Florida eKNOW Conference February 4, 2008

University of Central Floridawww.ucf.edu Agenda  Introduction  Background  Approach  Evaluation  Project LifeLike

University of Central Floridawww.ucf.edu Expert System Introduction Interface Knowledge Base User

University of Central Floridawww.ucf.edu Introduction  Focus on Interface Component  Text-based  Conversation-based  Idealistic view of Human Computer Interaction  Media and science fiction expectations  Open, unconstrained dialog  Natural conversational flow

University of Central Floridawww.ucf.edu Background  Natural Language Processing (NLP)  Relevant techniques  Not primary focus  Dialog System Design  General issue at hand  Context-Based Reasoning (CxBR)  Main architectural method

University of Central Floridawww.ucf.edu Natural Language Processing  Major issues in NLP (Wilks, 2005)  Linguistic Systems  Resolve ambiguities (ASR, syntactic, semantic)  Knowledge Representation  Relationship of language and logic  Information Corpora  Ontologies, tree banks, Semantic Web project  Statistical and Quantitative Methods  Machine learning techniques on linguistic data

University of Central Floridawww.ucf.edu Dialog System Design Dialog Manager Dialog History Interpreter Generator Dialog Model System Task Model Domain Knowledge Manager Domain Task Model Knowledge Base 1 Knowledge Base 2 Knowledge Base 3 Flycht-Eriksson and Jönsson, 2000

University of Central Floridawww.ucf.edu Chatbot Systems  Conversation Agents  General chatting techniques  ELIZA (Weizenbaum, 1966)  Persona-AIML (Galvão et al, 2004)  Genericity (Sansonnet et al, 2006)  Embodied Conversation Agents  Sam (Cassell et al, 2000)  Laura (Bickmore and Picard, 2004)  Mel (Lee et al, 2005)  Sergeant Blackwell (Traum, 2006)

University of Central Floridawww.ucf.edu Dialog Systems  Open issues  Evaluation process is too subjective  No tremendous breakthroughs since ELIZA  Naturalness still a barrier  Scarce work on context-based dialog management  Cognitive model-based systems require extensive expertise

University of Central Floridawww.ucf.edu Context-Based Reasoning  Contexts  Context-Transition Logic  Missions  Agent Interface Agent Interface Environment Data Agent Action Inference Engine Stensrud et al, 2004

University of Central Floridawww.ucf.edu Context-Based Methods in NLP  Situational contexts used for general NLP tasks  Speech recognition  Fügen et al, 2004  Sarma and Palmer, 2004  Serridge, 1997  Young, 1989  Context-based ML (Lieberman et al, 2005)

University of Central Floridawww.ucf.edu Context-Based Methods in NLP  Open issues  Context-based methods treated as a gimmicky technique  Still at a state of infancy  Use of context heavily prevalent for NLP ambiguity resolution tasks  Dialog management applications not fully explored

University of Central Floridawww.ucf.edu Approach  Goal Management  Allow for non-linear conversation flow  Support for goals  Asynchronous  Multiple  Illusion of open dialog  Limited to an expert domain, and the user is cognizant of the dialog system’s functionality as an expert entity  User’s goals are limited to those related to the chatbot’s expertise

University of Central Floridawww.ucf.edu Contexts In Goal Management  Context  Internal and external circumstances  Goal  Desired end state  CxBR  Context-goal relationships

University of Central Floridawww.ucf.edu Knowledge In Goal Management

University of Central Floridawww.ucf.edu Framework for Goal Management  Goal Recognition  NLP-based context activation  Goal Bookkeeping  Discourse Goal Stack Model (Branting et al, 2004)  Context Topology  Agent Goals  User Goals

University of Central Floridawww.ucf.edu Evaluation  Plagued by subjectiveness  Measuring Naturalness  PARADISE (Walker et al, 1997)  User questionnaire (Semeraro et al, 2003) (Rzepka et al, 2005)  Universal chatbot evaluation system (Shawar and Atwell, 2007)

University of Central Floridawww.ucf.edu Project LifeLike

University of Central Floridawww.ucf.edu Knowledge Manager Speech Disambiguator Context-based Dialog Manager LifeLike Dialog System LifeLike Recognizer NSF User Data General Knowledge AskAlex Ontology Spell Check Semantics Check Context Specific Knowledge LifeLike Speech Output Dictation String Phrase String Context Disambiguated String Context Dataset Context Dataset Response String Updated Data

University of Central Floridawww.ucf.edu Questions