1.
Lexical simplification approach to
support the accessibility guidelines
Lourdes Moreno, Rodrigo Alarcón,
Isabel Segura-Bedmar, Paloma Martínez

2.
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10% of the world’s population,
or 650 million people
lived with some type of disability
3
by 2050 there will be 2 billion
people over 60, or in Europe,
33% of society will be older
than 65

4.
Introduction Accessibility barriers involve everyone
in society.
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The readability and understandability of
texts that contain:
◎ long sentences
◎ unusual words
◎ complex linguistic structures
People with intellectual and learning
disabilities
A lack of approaches that improve
cognitive accessibility
=> Offer simplified texts
Introduction
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Websites which include simplified text
content, the simplification has been
created manually
◎ Manual simplification is expensive
◎ Information is constantly being
produced
Few tools that provide systematic
support to simplification processes.
Introduction
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Proposal Select cognitive
accessibility
guidelines for
design web user
interfaces
Develop tools to
provide support
to automatic
simplified text
processes
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Web Content Accessibility Guidelines
(WCAG) 2.1
◎ Standard to be followed in the majority
of the regulatory frameworks
Easy to Read guidelines
◎ People with intellectual disabilities
◎ International Federation of Library
Associations and Institutions (IFLA),
(ILSMH)
Plain Language guidelines
◎ All citizens, eAdministration documents
◎ Plain Language Action(PLAIN).
plainlanguage.gov ,
www.plainenglish.co.uk
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The Natural Language Processing (NLP)
provides methods and systematic
support to comply with cognitive
accessibility guidelines
This work:
Guideline: “Use simple lexicon”
Develop lexical simplification system
using NLP methods
Spanish and not dependent-domain
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Lexical
Simplification
System
Simplification process
(Shardlows, 2016)
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Step 1) CWI
Machine Learning approach (Support-
Vector Machine (SVM) classification
algorithm)
Data set from Complex Word
Identification (CWI) Shared Task,
Workshop BEA 2018
◎ Information of Wikipedia pages in
Spanish (collection of 14,280 entries)
Features:
◎ Length and Frequency
◎ Binary
◎ Word Embedding
◎ Easy to Read (E2R)
Lexical
Simplification
System
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Step 1) CWI
E2R dictionary which indicates if a
word is automatically qualified as
simple or not.
◎ Sources: web documents and
books in E2R elaborated by experts
(13400 simple words)
Process:
■ Tokenized
■ Lematized
■ Tagged
Lexical
Simplification
System
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Step 1) CWI
Evaluation
Workshop BEA 2018
c
The E2R dictionary provides a
significant improvement of
almost 2 points,
Lexical
Simplification
System
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Step 2) Substitution Generation
Select candidate substitutions for
each complex word
Linguistic database querying
strategy
◎ Dictionaries: Babelnet, Thesaurus
◎ For each complex word, a set of
synonyms are obtained
E2R dictionary and CWI process to
discard those complex synonyms
Lexical
Simplification
System
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Step 3) Substitution Selection
The most appropriate candidate is chosen
based on it being the simplest option within
the context of the sentence
Semantic similarity filtering strategy:
detect the synonyms that had the most
similar meaning to the original word
◎ Word embedding models (Word2Vec,
FastTest)
Lexical
Simplification
System
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User Interface for the system. It
generates accessible interfaces with
the generated simplified text
”Accessible technologies 2019" grant
awarded by:
EASIER tool
(ongoing)
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Conclusions
Complexity of the textual content
◎ Cognitive barriers experienced by
people with intellectual and learning
disabilities
Proposal:
◎ Cognitive accessibility guidelines:
■ Easy to Read
■ Plain Language
■ WCAG
◎ A lexical simplification system
Ongoing and future research:
◎ System: better performance, metrics
to measure lexical difficulty
◎ Tool Easier
◎ Test with users
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18.
Lexical simplification approach to
support the accessibility guidelines
Lourdes Moreno, Rodrigo Alarcón,
Isabel Segura-Bedmar, Paloma Martínez