--- title: "A Morphologically Sensitive Clustering Algorithm for Identifying Arabic Roots — Roeck 2000" description: "The paper groups Arabic words that share a root, for indexing in retrieval, with no dictionary. 21 references, cited by 12 papers here." authors: ["Anne N. De Roeck", "Waleed Al-Fares"] year: 2000 venue: "Proceedings of the 38th Annual Meeting of the Association for Computational Linguistics" source: "https://aclanthology.org/P00-1026/" doi: "10.3115/1075218.1075244" licence: "CC BY-NC-SA 3.0 (ACL Anthology, before 2016)" licence_url: "https://creativecommons.org/licenses/by-nc-sa/3.0/" summary_licence: "Elamur Cosmic License" canonical: "https://research.elamur.ai/free/en/papers/roeck-2000-morphologically-sensitive-clustering-algorithm-identifying/" --- [Elamur Research](https://md.research.elamur.ai/free/en/) · [this page in HTML](https://research.elamur.ai/free/en/papers/roeck-2000-morphologically-sensitive-clustering-algorithm-identifying/) [home](https://md.research.elamur.ai/free/en/) / [papers](https://md.research.elamur.ai/free/en/papers/) / [2000](https://md.research.elamur.ai/free/en/papers/2000/) / A Morphologically Sensitive Clustering Algorithm for Identifying Arabic Roots # A Morphologically Sensitive Clustering Algorithm for Identifying Arabic Roots **Authors:** [Anne N. De Roeck](https://md.research.elamur.ai/free/en/authors/anne-de-roeck/); Waleed Al-Fares · **Year:** 2000 · **Venue:** Proceedings of the 38th Annual Meeting of the Association for Computational Linguistics **Link:** [aclanthology.org/P00-1026](https://aclanthology.org/P00-1026/) · library `aclbulk-2000-roeck-morphologically-sensitive-clustering-algorithm-identifying` · **Licence:** [CC BY-NC-SA 3.0](https://creativecommons.org/licenses/by-nc-sa/3.0/) — summary only [**66** citations](https://openalex.org/works?filter=cites:W2012191724) OpenAlex, 2026-10-14 · [**12** citations in our library](https://md.research.elamur.ai/free/en/papers/roeck-2000-morphologically-sensitive-clustering-algorithm-identifying/cited-by/) of the 140,884 papers whose bibliographies we read · [Proceedings of the 38th Annual Meeting of the Association for Computational Linguistics](https://aclanthology.org/volumes/P00-1/) · [licence](https://creativecommons.org/licenses/by-nc-sa/3.0/) - [Publisher's page](https://aclanthology.org/P00-1026/) - [PDF](https://aclanthology.org/P00-1026.pdf) - [DOI 10.3115/1075218.1075244](https://doi.org/10.3115/1075218.1075244) - [OpenAlex](https://openalex.org/W2012191724) **Authors (2)** 1. [Anne N. De Roeck](https://openalex.org/A5109882660) [Semantic Scholar](https://www.semanticscholar.org/author/1619230985) · h 21 · 3,360 citations · 139 works 2. Waleed Al-Fares Citations and author metrics: OpenAlex, 2026-10-14; authors with the same name are not always told apart. ## What it is about The paper groups Arabic words that share a root, for indexing in retrieval, with no dictionary. It starts from Adamson and Boreham's bigram Dice score with single-link clustering and adds: light stemming to strip obvious affixes; word-boundary blanks; a "cross" bigram that joins the letters on either side of a weak letter; per-bigram weights (0.25 for weak letters, 0.5 for suspected affixes, 1 for the rest); and a Jaccard score in place of Dice. It was tested on five hand-clustered samples of unedited newspaper Arabic, from 232 to 750 words, with the three development sets used for tuning. On the held-out fifth set (314 words, a different domain) multi-word clusters containing infixes were found at 72.72%, against 9.09% for the baseline, and the abstract reports accuracy up to 94.06%. Single-word clusters stayed as clean as the baseline. The authors say the data are small and that scale is untested. ## Ideas - I2. The cross bigram for Hebrew verbs that lose a first or middle radical (pe-yod, ayin-waw): add the bigram that joins the neighbours of the weak letter, and measure on the verb forms in MACULA. - I3. A held-out test: cluster a few hundred Hebrew forms by hand into root groups, count the recall of multi-word groups that contain weak or infixed forms, and run it once per release. Recall is the measure, as in the paper. ## For Mova - I1. Use the weighting scheme for unknown Hebrew words: lower the weight of weak consonants (aleph, waw, yod, and he of lamed-he verbs) and mark the prefix letters (ה ו ב כ ל מ ש) as suspect, in a similarity score between an unknown unpointed token and the known lemmas in `tools/hbo`. I1 and I2 apply to the fallback that guesses the lemma of an unknown word in `tools/hbo`, with the lexicon in [languages/hbo/10-lexicon.md](https://mova.elamur.ai/free/en/docs/languages/hbo/10-lexicon/). I3 is a held-out test set for that fallback. ## Institutions [🎓**University of Essex** Colchester · United Kingdom 22 works · 2,852 citations](https://md.research.elamur.ai/free/en/universities/university-of-essex/) Topics[Morphology](https://md.research.elamur.ai/free/en/topics/morphology/) · [Semitic languages](https://md.research.elamur.ai/free/en/topics/semitic-languages/) ## Cite Cite as Anne N. De Roeck and Waleed Al-Fares. 2000. A Morphologically Sensitive Clustering Algorithm for Identifying Arabic Roots. Proceedings of the 38th Annual Meeting of the Association for Computational Linguistics. The paper itself, not this card. BibTeX from the library's record of the work. [DOI 10.3115/1075218.1075244](https://doi.org/10.3115/1075218.1075244) ```bibtex @inproceedings{roeck2000morphologically, title = {{A Morphologically Sensitive Clustering Algorithm for Identifying Arabic Roots}}, author = {Anne N. {De Roeck} and Waleed Al-Fares}, booktitle = {Proceedings of the 38th Annual Meeting of the Association for Computational Linguistics}, year = {2000}, doi = {10.3115/1075218.1075244}, url = {https://doi.org/10.3115/1075218.1075244} } ``` - [← previous Multitiered Nonlinear Morphology Using Multitape Finite Automata: A Case Study on Syriac and Arabic](https://md.research.elamur.ai/free/en/papers/kiraz-2000-multitiered-nonlinear-morphology-multitape-finite/) - [next → Importance of Pronominal Anaphora Resolution in Question Answering Systems](https://md.research.elamur.ai/free/en/papers/vicedo-2000-importance-pronominal-anaphora-resolution-question/) - [↑ back to papers of 2000](https://md.research.elamur.ai/free/en/papers/2000/) ## References 21 references, 1 of them with a card of ours. ↗ leads to the work, «find» searches for one we have no id for yet. 1. Adams, E. (1991) A Study of Trigrams and their feasibility as Index Terms in a full text Information Retrieval System. PhD Thesis, George Washington University, USA. [find](https://scholar.google.com/scholar?q=Adams%2C+E%2E+%281991%29+A+Study+of+Trigrams+and+their+feasibility+as+Index+Terms+in+a+full+text+Information+Retrieval+System%2E+PhD+Thesis%2C+George+Washington+University%2C+USA%2E) 2. Adamson, George W. and J. Boreham (1974) The use of an association measure based on character structure to identify semantically related pairs of words and document titles. Information Storage and Retrieval,. Vol 10, pp 253-260 [find](https://scholar.google.com/scholar?q=Adamson%2C+George+W%2E+and+J%2E+Boreham+%281974%29+The+use+of+an+association+measure+based+on+character+structure+to+identify+semantically+related+pairs+of+words+and+document+titles%2E+Information+Storage+and+Ret) 3. Al-Fedaghi Sabah S. and Fawaz Al-Anzi (1989) A new algorithm to generate Arabic root-pattern forms. 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