Towards Resolving Morphological Towards Resolving Morphological Ambiguity in ArabicAmbiguity in Arabic

Intelligent Language Tutoring Intelligent Language Tutoring FrameworkFramework

Khaled ShaalanKhaled Shaalan

Doaa SamyDoaa Samy

Marwa MagdyMarwa Magdy

• Introduction.• Arabic Morphological Ambiguity

Problem• The Proposed Disambiguation System• Evaluation & Results• Conclusions

Outlines

• Introduction• Arabic Morphological Ambiguity

Problem• The Proposed Disambiguation System• Evaluation & Results• Conclusions

Outlines

Introduction

curriculum sequence

adaptive presentation

Adaptive navigation

error remediation

Intelligent Language Tutoring System

• A computer-based educational system that allows simulation of a human tutor.• its objective is to enhance teaching and learning of foreign languages.

Intelligent feedback to student solutions

• Lack of resources, such as Learner corpus for Arabic language

• Lack of tools dealing with ill-formed input• In ILTS, relaxing the constraints of the

language to analyze learner’s answer results in handling more interpretations than systems designed for only well-formed input

Main Challenges

Main Challenges (cont‘d)Main Challenges (cont‘d)

Intelligent Language Tutoring System

Analyzes

Erroneous Learner Answer

Use techniques, such as constraints

relaxation

More Interpretation

(said) قالت

In well formed systems:

- 3rd female sg past verb

In ILTS:•3rd person female sg

•1st person sg past verb•2nd person male sg past verb2nd person female sg past verb

• Introduction• Arabic Morphological Ambiguity

Problem• The Proposed Disambiguation System• Evaluation & Results• Conclusions

Outlines

• Arabic language is one of the Semitic languages that is defined as a diacritized language.

• Unfortunately, diacritics are rarely used in current Arabic writing conventions.

• So two or more words in Arabic are homographic

Arabic Morphological Ambiguity

Homographic Example

WordLemmaDifferent Interpretations

(bring back ) يع�دأعاديعد

(return ) يعدعاد

(promise ) يع�دوعد

�عد�عد ( count )َی

ع�د�أعد ( prepare )َی

Factors of Arabic Ambiguity

Orthographic alteration operations

such as deletion

Some verb prefixes

and suffixes can be

homographic

Ambiguity of

Undiacritized verb Arabic

patterns

Prefixes and suffixes can

produce a form homographic with

another word class

Main Factors

For example, the deletion of the letter (و) in taking the present (imperfect) tense of the trilateral root - د- ع w-E-d/, it appears in/ وwritten texts as يعد (promise).

For example, the perfect verb suffix ت can indicate either: 1) first person singular, 2) second person singular masculine, 3) second person singular feminine, or 4) third person singular feminine.

For example, the /faEala/ فعلand فع�ل /faE~ala/.

For example, the word أسد can be interpreted as أسد (lion) or د� -I) أس�Block).

• Introduction• Arabic Morphological Ambiguity

Problem• The Proposed Disambiguation System• Evaluation & Results• Conclusions

Outlines

The Proposed SystemThe Proposed System

Arabic ILTS

Item banking

Disambiguation Module

Word Analyzer Module

Error Classification

ModuleTutoring Module

Learner Answer

Feedback Message

Possible Word Analyses

Selected Word Analysis

Error Type

Question:Build a sentence using the following roots:

- - - - م- و د ق، ح ل، و -q-w-l, H-q, d/ قw-m/

The question goal is:conjugation hollow verb in imperfect tense active voice

Suffix ’‘

TenseVoice activeMood indicative

Subject Features 1st sgObject Features ’‘

Feature Value

Answer أقول

Root - ل- و ق

Lexical Category verb

Pattern فعل

Verb Type hollow

Prefix أ

imperfect

دائما الحق قالتو(I always said the truth) Tense

Voice active

Subject Features 1st sg

Object Features ’‘

Feature Value

Stem قال

Prefix ’‘

Suffix ت

Lexical Category verb

Verb Type hollow

Pattern فعل

perfect

Stem Error Representation:Added middle letter

ل ا ق

Affix Error Representation:Added final letter

ت+ و قال

•Verb tense error•Verb conjugation•Vowel letters

•Incorrect use of perfect verb instead of imperfect

Disambguation ModuleDisambguation Module

Affix Collection

Prioritized Conditions

Pattern Collection

No Action

Multiple Analyses

Multiple Analyses

Selected Analysis

Prioritized ConditionsPrioritized Conditions

Item banking

The question goal is to test passive voice

Multiple Analyses

Yes

No

Select Passive Analysis

Select Active Analysis

Prioritized ConditionsPrioritized Conditions

Item banking

The question goal is to test

imperative tense

Multiple Analyses

Yes

No

Select Imperative Verb

Analysis

Select perfect or imperfect verb

Analysis

ExampleExample

If the learner writes the following sentence:االرز جدتي ( My-grandmother sells the-rice)تباع

:The system produces two analyses

If the learner writes the following sentence:االرز جدتي ( My-grandmother sells the-rice)تباع

The system produces two analyses:

Third person singular feminine imperfect verb in the active

voice with converted middle letter

Third person singular feminine imperfect verb in the passive

voice

Disambguation ModuleDisambguation Module

Affix Collection

Prioritized Conditions

Pattern Collection

No Action

Multiple Analyses

Multiple Analyses

Selected Analysis

ExampleExample

If the learner writes the following sentence:قتل جريمة في تورطت Mohamed was-involved in )محمد

murder crime )

:The system produces four analyses

If the learner writes the following sentence:قتل جريمة في تورطت Mohamed was-involved in)محمد

murder crime )

The system produces four analyses:

First person singular perfect

verb in the active voice

Second person singular

masculine perfect verb in the active voice

Second person singular feminine

perfect verb in the active voice

Third person singular feminine

perfect verb in the active voice

Singular perfect verb conjugation in the

active voice

Disambguation ModuleDisambguation Module

Affix Collection

Prioritized Conditions

Pattern Collection

No Action

Multiple Analyses

Multiple Analyses

Selected Analysis

ExampleExample

If the learner writes the following sentence:جديد بيت الي نقلوا وجدتي my-grandfather and )جدي

my-grandmother moved to a new house )

:The system produces two analyses

If the learner writes the following sentence:جديد بيت الي نقلوا وجدتي my-grandfather and)جدي

my-grandmother moved to a new house )

The system produces two analyses:

Third person masculine plural perfect verb in the active voice following the

pattern 'فعل'.

Third person masculine plural perfect verb in the active voice following the

pattern 'فع�ل'.

Third person masculine plural perfect verb in the

active voice instead of dual

• Introduction.• Arabic Morphological Ambiguity

Problem.• The Proposed Disambiguation System.• Evaluation & Results• Conclusions

Outlines

Evaluations & Results• A real test set that consists of 116 real Arabic

sentences is collected • The system successfully solved 60% of the cases

Evaluation & Results

Evaluation Problems Classification

Orthographic match

between un-diacritized

forms

Additional- orthographic matches as a

result of relaxing a constraint

ProblemsFor example, the word تناول; 1) the noun تناول /tanAwul/ (dealing with/ eating), 2) the perfect verb تناول /tanAwala/ (he/it-dealt with/ ate), or 3) the imperfect verb تناول /tu-nAwil/ (hand over/ deliver).

For example, the erroneous word :أجوب

1) the imperfect verb أجيب />u-jiyb/ (I-answer),

2) 2) or imperfect verb أجوب />a-juwb/ (I-explore).

• Introduction• Arabic Morphological Ambiguity

Problem• The Proposed Disambiguation System• Evaluation & Results• Conclusions

Outlines

• The ambiguity problem presents a challenge to ILTS • The preferred method in ILTS for disambiguating

multiple readings should consider the likelihood of an error and the difficulty of concepts

• If a large tagged learner corpus exist then the ambiguity problem can be resolved by considering the likelihood of errors

Conclusions

Thank you