Towards Resolving Morphological Ambiguity in Arabic Intelligent Language Tutoring Framework Khaled Shaalan Doaa Samy Marwa Magdy Outlines • 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 Introduction curriculum sequence Adaptive navigation Intelligent Language Tutoring System adaptive presentation • A computer-based educational system that allows simulation of remediation a human tutor. error • its objective is to enhance teaching and learning of foreign languages. Intelligent feedback to student solutions Main Challenges • 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 (cont‘d) Use techniques, such as constraints قالت (said) Analyzes relaxation In well formed systems: -In 3rdILTS: female sg past Intelligent Language Tutoring System•3rd person female verb sg •1st person sg past verb •2nd person male sg past verb 2nd person female sg past verb Erroneous Learner Answer More Interpretation Outlines • Introduction • Arabic Morphological Ambiguity Problem • The Proposed Disambiguation System • Evaluation & Results • Conclusions Arabic Morphological Ambiguity • 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 Homographic Example Word Lemma Different Interpretations يعد أعاد عاد وعد (bring back) ي ِعد (return) يعُد (promise) ي ِعد عد أعد (count) ّيَعُد (prepare) ّيُ ِعد Factors of Arabic Ambiguity Fordeletion example,ofthe perfect verb suffix ت For example, the the For example, the word أسدcan be can indicate either: 1) first person letter ( )وin taking the present Factors For example, فعلor س ًد interpreted as أسدthe (lion) ٌ (أIsingular, 2)Main second person singular (imperfect) tense of the trilateral and ف ًعل Block)./faEala/ masculine, 3) second person singular root د-ع- و/w-E-d/, it appears in /faE~ala/. feminine, or 4) third person singular written texts asfeminine. ( يعدpromise). 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 Outlines • Introduction • Arabic Morphological Ambiguity Problem • The Proposed Disambiguation System • Evaluation & Results • Conclusions The Proposed System Error Arabic ILTSAffix Stem Feature ErrorRepresentation: Representation: Value Feature Value final letter Added Added middle letter Stem ت ل و+اقال قالق Answer Possible Word أقولAnalyses Prefix ‘’ Root ل- و-ق Suffix •Verb tense تerror Question: LexicalWord Category verb Analyzer Disambiguation •Verb conjugation Build a sentence using the following Lexical Category Module Module verb Pattern فعل The question goal is: •Vowel hollow letters roots: Verb Type Item banking conjugation Verb Type hollow hollow verb in م-وuse - د،قof- ح،ل-و- ق/q-w-l, H-q, d-w•Incorrect Pattern فعل Selected Word Analysis دائما الحق قالتو Prefix أ imperfect tense active voice Learner Answer m/ perfect verb insteadSuffix (I always said the truth) perfect ‘’Tense Feedback Message of imperfect active Errorimperfect TypeVoice Tense Error Object Features Classification‘’ Voice active Tutoring Module Mood indicative Subject FeaturesModule1st sg Subject Features 1st sg Object Features ‘’ Disambguation Module Prioritized Conditions Affix Collection Multiple Analyses Pattern Collection No Action Selected Analysis Multiple Analyses Prioritized Conditions The question goal is to test passive voice Select Passive Analysis Select Active Analysis Item banking Multiple Analyses Prioritized Conditions The question goal is to test imperative tense Item banking Multiple Analyses Select Imperative Verb Analysis Select perfect or imperfect verb Analysis Example If the learner writes the following sentence: (My-grandmother sells the-rice ) تباع جدتي االرز 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 Module Prioritized Conditions Affix Collection Multiple Analyses Pattern Collection No Action Selected Analysis Multiple Analyses Example If the learner writes the following sentence: (Mohamed was-involved in murder محمد تورطت في جريمة قتل crime ) The system produces four analyses: First person singular perfect verb in the active voice Second person Second person Singular perfect verb singular singular masculine conjugation in the feminine perfect verb in perfect verb in active voice the active voice the active voice Third person singular feminine perfect verb in the active voice Disambguation Module Prioritized Conditions Affix Collection Multiple Analyses Pattern Collection No Action Selected Analysis Multiple Analyses Example If the learner writes the following sentence: (my-grandfather and my- جدي وجدتي نقلوا الي بيت جديد grandmother moved to a new house ) The system produces two analyses: Third person masculine Third person masculine Third person masculine in the plural perfect verb inplural the perfect verb plural perfect verb in the active voice following the activeofvoice following the active voice instead pattern ''فعل. pattern ''ف ًعل. dual Outlines • Introduction. • Arabic Morphological Ambiguity Problem. • The Proposed Disambiguation System. • Evaluation & Results • Conclusions Evaluations Results Evaluation &&Results • A real test set that consists of 116 real Arabic sentences is collected • The system successfully solved 60% of the cases Evaluation Problems Classification Orthographic match between undiacritized forms For example, the erroneous word For example, the word ;تناول : أجوبProblems 1) the noun تناول/tanAwul/ (dealing 1) the imperfect verb أجيب />u-jiyb/ with/ eating), (I-answer), 2) the verb تناولverb /tanAwala/ 2) perfect 2) or imperfect أجوب/>a(he/it-dealt ate), or juwb/with/ (I-explore). 3) the imperfect verb تناول/tuAdditionalorthographic nAwil/ (hand over/ deliver). matches as a result of relaxing a constraint Outlines • Introduction • Arabic Morphological Ambiguity Problem • The Proposed Disambiguation System • Evaluation & Results • Conclusions Conclusions • • • 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 Thank you