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A Tool to Support Ontology Creation Based on IncrementalMini-ontology Merging

Zonghui Lian

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Introduction

Ontology-based information extraction Robust to change Multi-slot filling Source-independent Drawback: ontology has to be generated manually

Tango (Table ANalysis for Generating Ontologies) An information gathering engine that infers the

unknown objects and relations in a known context into ontologies automatically

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TANGO

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TANGO

Source table understanding Constraints discovery Concept matching Ontology merging Domain ontology adjusting

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The Flow of Ontology Integration

Ontology mapping

KB conflict checking

Make suggestion

Data storage

Ontology Merging

Mini-ontology

User’s interactions

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Research Issues

Name conflict detection Union/selection detection and merging Composition/decomposition detection and merging Constraint conflict detection Relationship set conflict detection New concept detection and merging Ontology consistency checking after integration

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Name Conflict Detection

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Union/Selection Detection & Merging

Graduate Student is a subset of Student

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Composition/Decomposition Detection & Merging

Name = First Name + Last Name

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Constraint Conflict Detection

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Constraint Conflict Detection

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Relationship Set Conflict Detection

?

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Relationship Set Conflict Detection

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Other Issues

New concept detection and merging Ontology consistency checking after

mapping

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Ontology Mapping

Based on mapping technique introduced in EXD04

Need to make improvement and change according to the requirements of ontology mapping

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Ontology Mapping

Data-value characteristics detectionSchema mapping: data values in tablesOntology mapping: dictionaries & data values

in a set of source tables Reference ontology inference

Schema mapping: reference ontologyOntology mapping: data frame library (option)

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Ontology Mapping

New concept detectionSchema mapping: noneOntology mapping: mark unmatched attributes

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Ontology Mapping

Relationship set mappingSchema mapping: noneOntology mapping

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Ontology MappingPerson|Student has Name

Graduate Student has Name

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Ontology Mapping

? Phone Extension

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Ontology Mapping

Detailed mapping information detectionSchema mapping: need to be improvedOntology mapping:

Base on values to detect subset/superset and merge/split

Human experts refine interactively

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Ontology Merging

Name conflict Based on growing ontology

Union/selection mergingGeneralization/specialization

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Graduate Student is a subset of Student

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Ontology Merging

Composition/decomposition merging Aggregation

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Name = First Name + Last Name

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Ontology Merging

Relationship set mergingMap w/out conflicts: mergeMap with conflict(s):

Fake conflicts: resolve the conflict Real conflicts: Add new relationship set(s) or

change the current one

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Evaluation

Users A package (more than just software) Users’ report Analysis

Precision

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Contributions

Can extend DEG's ontology-based data extraction system with a set of ontology growing features

Can contribute to generate a domain-specific ontology with minimal human intervention