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How Useful are Natural Language Interfaces to the Semantic Web for Casual End-users?. Esther Kaufmann and Abraham Bernstein Presented By Stephen Lynn. Overview. Natural Language Interfaces Goals/Objectives Introduce 4 Interfaces Experiment Evaluation Results Future Work.
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How Useful are Natural Language Interfaces tothe Semantic Web for Casual End-users? Esther Kaufmann and Abraham Bernstein Presented By Stephen Lynn
Overview • Natural Language Interfaces • Goals/Objectives • Introduce 4 Interfaces • Experiment • Evaluation Results • Future Work
Natural Language Interfaces • Plain text queries • Phrases • Full Sentences • Challenges • Linguistic Variability (ambiguous meaning) • Domain Independence • Retrieval Performance (linked to portability) • Usefulness of NLIs
Goals/Objectives Usability of NLIs Usefulness of NLIs
Evaluation Interfaces • Portable • Domain-Independent • Good Performance • 4 Interfaces • Least to Most Restrictive
NLP-Reduce • Free-form text query • Remove Stop Words/Puncuation • Word Stemming • Identify Triple Structures (no details) • Enhanced Triple Store (WordNet) • Generate SPARQL • Return Results
Querix • Parse Query • Extract Query Skeleton from Syntax Tree • Identifies Triple Patterns • Match Triples to Knowledge Base Resources • Generate SPARQL • Enhanced with WordNet Synonyms • Return Results
Querix – Ambiguity Resolution • What is the biggest state in the US?
Ginseng • UI based on a grammar • Built dynamically from target knowledgebases • Incremental Parser • Offer possible completions (code completion) • Only accepts entries in list • No invalid queries • Convert to SPARQL • Return Results
Symantic Crystal • Graphical Display of Ontology • Select Elements in Ontology • No Invalid Queries • Specify Constraints • Incrementally Build Query • Generate SPARQL • Return Results
Usability Study • How usable and useful are NLI applications? • Setup • 48 subjects • 4 interfaces • Same 4 questions for each interface (minor changes) • Area of Alaska? • Number of lakes in Florida? • States that have city named Springfield? • Rivers run through state that has largest city in US? • Change sequence of interfaces
Experiment • Read Introduction Notes • Instructions on Interface #1 • Answer 4 questions with interface • Fill out Usability survey about Interface • Repeat 2-4 for other Interfaces • Fill out Comparison Questionnaire
Strengths • Good General Points • Automation is good (not Sematic Crystal) • Result format affects user trust • Balance between freedom and restriction • User Evaluation • Analysis
Weaknesses • Completion time not a deciding factor in satisfaction • Still pushing Semantic Crystal • Personal Attachment • Unclear distinction between QL and Interface
Future Work • Compare with more NLIs • Multiple Domains • Single Infrastructure w/Different Uis • Evaluate Usability/Usefulness