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Building a Terminological Database from Heterogeneous Definitional Sources. Smaranda Muresan, Peter T. Davis Samuel D. Popper, Judith L. Klavans Columbia University. Why Terminology is Important?. Each agency and each department might have different ways to define the same concept

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Building a terminological database from heterogeneous definitional sources

Building a Terminological Database from Heterogeneous Definitional Sources

Smaranda Muresan, Peter T. Davis

Samuel D. Popper, Judith L. Klavans

Columbia University

May 21, 2003


Why terminology is important
Why Terminology is Important? Definitional Sources

  • Each agency and each department might have different ways to define the same concept

  • Working with multiple databases requires understanding the data across multiple agencies and domains


What s an employee
What’s an Employee? Definitional Sources

An appointed officer or employee of USDA including special Government employees (collaborators, consultants and panel members). The term excludes independent contractors.

An individual who is engaged or compensated by a railroad or by a contractor to a railroad, who is authorized by a railroad to use its wireless communications in connection with railroad operations.

US Department of Agriculture

Federal Railroad Administration

A person who works for wages or salary in the service of an employer.

The term "employee" does not include a director, trustee, or officer.

Mine Safety and Health Administration

US SEC


Desiderata for terminological resources
Desiderata for Terminological Resources Definitional Sources

  • Capture the ongoing evolution of language

  • Provide consistency, ease of sharing and integration across agencies.


Architecture
Architecture Definitional Sources

Building the terminological DB

Collection

Use

Heterogeneous Definitional Corpus

SemanticAnalysis

Database Building

GetGloss

ParseGloss

TerminologicalDatabase

Definder

database query

dynamic sources

relations among concepts and their attributes

fast access, flexibility, sharing


Collection
Collection Definitional Sources

  • Motivation

    • Definitions are rich in terminological knowledge

    • On-line dictionaries are static and generally incomplete

    • Need to capture the evolution of language

  • Solution

    • GetGloss – identification and extraction of glossaries

    • Definder - extraction of definitions from online free text

Acquisition of Heterogeneous Definitional Corpus

GetGloss

Definder


Building the terminological db

Motivation Definitional Sources

Need to identify relationships among concepts

e.g. synonyms, hypernyms, cross-reference

Need to store this conceptual information for easy and fast access and integration

Building the Terminological DB

Gasoline: See Motor Gasoline (Finished).

Motor Gasoline (Finished): A complex mixture of relatively volatile hydrocarbons with or without small quantities of additives, blended to form a fuel suitable for use in spark-ignition engines. Motor gasoline, as defined in ASTM Specification D 4814 or Federal Specification VV-G-1690C, is characterized as having a boiling range of 122 to 158 degrees Fahrenheit at the 10 percent recovery point to 365 to 374 degrees Fahrenheit at the 90 percent recovery point. "Motor Gasoline" includes conventional gasoline; all types of oxygenated gasoline, including gasohol; and reformulated gasoline, but excludes aviation gasoline.

Term: Motor Gasoline (Finished)

Source: (source (agency "EIA") (resource "Gasoline Glossary") (url …)

Paren-modifier: Finished

Full Definition: A complex mixture... for use in ….

Core Definition: A complex mixture ... for use in spark-ignition engines

Genus Phrase: A complex mixture of relatively volatile hydrocarbons

Head Genus Word: hydrocarbons

Properties:

UsedIn:

spark-ignition engines

Excludes-Includes:

includes conventional gasoline

includes gasohol

excludes aviation gasoline...

  • Solution

    • Transform definitional text into conceptual data

    • ParseGloss – partial semantic analysis of definitions to identify relations between concepts

    • Store data into a relational database

Semantic Analysis

Database Building

ParseGloss

TerminologicalDatabase

Definitional Corpus


Database use
Database Use Definitional Sources

  • Motivation

    • Enable the user to access the richness of terminological knowledge

    • Assure easy and fast access to data

    • Enable data sharing and integration across agencies

    • Enable dynamic update of data

SQL query for inflammation

1. Redness, swelling, heat and pain resulting from injury to tissue (parts of the body underneath the skin). Also known as swelling.

2. A characteristic reaction of tissues to disease or injury; it is marked by

four signs: swelling, redness, heat, and pain.

3. The reaction of tissue to injury .

4. A response to irritation , infection , or injury , resulting in pain ,

redness , and swelling .

  • Solution

    • Query module for the relational database (SQL)

TerminologicalDatabase


Putting it all together
Putting It All Together Definitional Sources

Building the terminological DB

Collection

User

Heterogeneous Definitional Corpus

SemanticAnalysis

Database Building

GetGloss

ParseGloss

TerminologicalDatabase

Definder

database query

dynamic sources

relations among concepts and their attributes

fast access, flexibility, sharing


Getgloss automatic glossary extraction
GetGloss – Automatic Glossary Extraction Definitional Sources

  • DGRC project

  • Given a URL find the glossary file

  • Challenges:

    • glossaries can constitute small parts of a web page, being embedded inside

    • there is no standard HTML tag formatting for marking <term,definition> pairs

    • a web page can contain <term,information> pairs, where information is not a definition.


True positive
True Positive Definitional Sources


False positive
False Positive Definitional Sources


Algorithm
Algorithm Definitional Sources

  • Two step algorithm

  • Identification Component

    • Find candidate glossaries

    • Keyword + Rule-based algorithm (6 rules)

      • “glossary”, “dictionary” in HTML tags

      • Terms in alphabetical order …

  • Classification Component

    • Filter out false positives

    • Rule-based method (9 rules)

      • e.g filter if term is a Named Entity (e.g California)

    • Statistical method using SVM


Evaluating the identification component
Evaluating the Identification Component Definitional Sources

  • 10,000+ pages from 5 different sites

    • 1,000 page sample: no glossaries (n=13)

  • 286,579 page sample from 268 domains

    • P=53%

  • Estimating recall is hard

  • Precision and Recall both very sensitive to perturbations (p=0 vs. p=53%)

Klavans et. al (dg.o 2002)


Evaluating the classification components
Evaluating the Classification Components Definitional Sources

  • GetGloss Categorizer assigns a score to each candidate based on a linear combination of weighted features

  • Corpus: 2400 glossary candidates

  • Test: 300 randomly chosen, manually categorized glossary candidates


Classification component performance
Classification Component Performance Definitional Sources

0 if Score < -100

1 if -100 ≤ Score < -50

2 if -50 ≤ Score < 0

3 if 0 ≤ Score < 50

4 if 50 ≤ Score < 100

5 if 100 ≤ Score




Definder
Definder Definitional Sources

  • Part of NSF funded digital library project

    • Medical domain

    • Extract definitions from consumer oriented medical text

  • Corpus

    • Medical articles written by doctors for lay audience

    • Different genre (articles, manual chapters)


Algorithm1
Algorithm Definitional Sources

  • Shallow parsing

    • Simple definitions (e.g NP-NP pairs for synonyms)

    • Candidate complex definitions

  • Full parsing (Charniak’00 parser)

    • appositions, relative clauses, complex definitional sentences


Definition patterns and examples
Definition Patterns and Examples Definitional Sources

  • Simple definitions

    NP ( NP )

    moving x-ray pictures ( angiograms )

    hypertension ( high blood pressure )

    NP -- NP --

    tachycardia – racing heartbeat -- ….

    NP of NP ( NP )

    enlargement of the heart muscle ( hypertrophy )


Definition patterns and examples1
Definition Patterns and Examples Definitional Sources

  • Complex definitions

    [S[CNP NP , [CNP CNP CNP] CNP] [VP … VP] S]

    Angina, the pressing chest pain most people associate with heart problems, ….

    [S … [CNP NP -- [CNP CNP CNP] CNP]S]

    … atherosclerosis – the progressive narrowing of the heart’s own arteries by cholesterol plaque buildups, which starves the heart itself for oxygen and nutrients.


Evaluation
Evaluation Definitional Sources

  • Quantitative

    • 4 human subjects , 10 articles

    • 53 definitions – gold standard

    • DEFINDER – p=86.27%, r = 84.60%

  • Qualitative

    • Usefulness and readability (non-specialists)

    • Completeness and accuracy (medical specialists)

Klavans and Muresan(JCDL’01)

Muresan and Klavans (LREC’02)


Coverage of on line dictionaries
Coverage of On-line Dictionaries Definitional Sources


Characteristics of automatically built definitional corpus
Characteristics of Automatically Built Definitional Corpus Definitional Sources

  • Large amount of data

  • Heterogeneous

    • Structure

    • Language

    • Semantics

  • Multiple definitions of the same term

Environment domain

Column Ozone: ozone between the Earth's surface and outer space. Ozone levels can be described in several ways. One of the most common measures is how much ozone is in a vertical column of air. The dobson unit is a measure of column ozone. Other measures include partial pressure, number density, and concentration of ozone, and can represent either column ozone or the amount of ozone at a particular altitude.

Medical domain

Arrhythmia: A disturbance in the beating pattern of the heart .

Ozone: (O3)A colorless gas with a pungent odor, having the molecular form of O3 , found in two layers of the atmosphere, the stratosphere (about 90% of the total atmospheric loading) and the troposphere (about 10%). Ozone is a form of oxygen found naturally in the stratosphere that provides a protective layer shielding the Earth from ultraviolet radiation's harmful health effects on humans and the environment. In the troposphere, ozone is a chemical oxidant and major component of photochemical smog. Ozone can seriously affect the human respiratory system. See atmosphere, ultraviolet radiation. <http://www.epa.gov/globalwarming/glossary.html.xml>

Ozone: A form of oxygen in which atoms combine in groups of three .

<1006_Oxygen_therapy>

Ozone: (O3)A colorless gas with a pungent odor, having the molecular form of O3 , found in two layers of the atmosphere, the stratosphere (about 90% of the total atmospheric loading) and the troposphere (about 10%). Ozone is a form of oxygen found naturally in the stratosphere that provides a protective layer shielding the Earth from ultraviolet radiation's harmful health effects on humans and the environment. In the troposphere, ozone is a chemical oxidant and major component of photochemical smog. Ozone can seriously affect the human respiratory system. See atmosphere, ultraviolet radiation. <http://www.epa.gov/globalwarming/glossary.html.xml>

Ozone: A form of oxygen in which atoms combine in groups of three .

<1006_Oxygen_therapy>

  • Addison Disease

  • -a rare disease that results from a deficiency in adrenocortical hormones

  • - an endocrine disorder that affects about 1 in 100,000 people

  • - a degenerative disease that is characterized by low blood pressure and dark brown pigmentation of the skin


Putting it all together1
Putting It All Together Definitional Sources

Building the terminological DB

Collection

User

Heterogeneous Definitional Corpus

SemanticAnalysis

Database Building

GetGloss

ParseGloss

TerminologicalDatabase

Definder

database query

dynamic sources

relations among concepts and their attributes

fast access, flexibility, sharing


Parsegloss partial semantic analysis
ParseGloss – Partial Semantic Analysis Definitional Sources

  • Challenges – heterogeneous collection of definitions

  • Focus on identifying the main semantic relations among concepts

  • Partial Semantic Analysis based on shallow parsing

    • Genus phrase and genus term

    • Synonyms, cross-reference

    • Other common relations between the defined term and the concepts inside the definition


Example
Example Definitional Sources

Term: Motor Gasoline (Finished)

Source: (source (agency "EIA") (resource "Gasoline Glossary") (url …)

Paren-modifier: Finished

Full Definition: A complex mixture... for use in ….

Core Definition: A complex mixture ... for use in spark-ignition engines

Genus Phrase: A complex mixture of relatively volatile hydrocarbons

Head Genus Word: hydrocarbons

Properties:

UsedIn:

spark-ignition engines

Excludes-Includes:

includes conventional gasoline

includes gasohol

excludes aviation gasoline


Evaluation1
Evaluation Definitional Sources

  • Task - User based evaluation to

    • build a gold standard for genus phrase

    • to ask people to identify the most important properties inside each definition

  • Data

    • 100 term-definition pairs

    • 7 different glossaries

    • 26 subjects


Results
Results Definitional Sources

  • Complex evaluation

  • Different notions of agreement and overlap:

    • Head only – 64% precision

    • Genus phrase – 59% precision


Building the database
Building the Database Definitional Sources

  • Relational database

  • XML – data transfer

  • Statistics

    • ~8000 terms

    • ~12,500 definitions

    • ~2000 different sources (web pages, articles, etc.)



Putting it all together2
Putting It All Together Definitional Sources

Building the terminological DB

Collection

User

Heterogeneous Definitional Corpus

SemanticAnalysis

Database Building

GetGloss

ParseGloss

TerminologicalDatabase

Definder

database query

dynamic sources

relations among concepts and their attributes

fast access, flexibility, sharing


Query the terminological database
Query the terminological Database Definitional Sources

- Term: Audit

Definition: An examination of the financial statements, accounting records, and other supporting evidence of an institution…

Source: www.fdic.gov

- Term: Industrial radiography

Definition: means an examination of the structure of materials…

Source: www.nrc.gov

- Term: Medical Surveillance

Definition: is the systematic examination of medical monitoring data to determine…

Source: www.osha.gov


Conclusions
Conclusions Definitional Sources

  • Proposed a framework for solving the heterogeneous terminology problem

    • Automatically building a heterogeneous collection of definitions from dynamic sources

    • Partial semantic analysis of the definitions to identify main semantic relations between concepts

    • Building a database for fast, easy access, dynamic update of data, sharing across agencies


Future work
Future Work Definitional Sources

  • Deep domain specific semantic analysis

  • But, how to automatically classify the glossary entries and definitions?

    • Based on the classification of their source (sites, articles, etc)

  • When and how to merge different definitions for the same term?

  • Integrate this acquired terminological knowledge into the DGRC system


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