---
license: mit
task_categories:
- token-classification
language:
- ar
tags:
- segmentation
dataset_info:
  features:
  - name: doc_id
    dtype: string
  - name: tokens
    list: string
  - name: labels
    list: int64
  - name: text
    dtype: string
  - name: label_str
    dtype: string
  splits:
  - name: test
    num_bytes: 3079281
    num_examples: 262
  - name: dev
    num_bytes: 3193451
    num_examples: 222
  - name: train
    num_bytes: 2497791
    num_examples: 174
  download_size: 1656979
  dataset_size: 8770523
configs:
- config_name: default
  data_files:
  - split: test
    path: data/test-*
  - split: dev
    path: data/dev-*
  - split: train
    path: data/train-*
---

# Arabic Sentence Segmentation Shared Task 2026
For details about the shared task, evaluation scripts, leaderboard, and submission guidelines, visit:
https://www.araseg.aramlab.ai/


## Dataset Summary

AraSeg is the first comprehensive benchmark for Arabic sentence segmentation.
The corpus is designed to support research on sentence segmentation in Modern Standard Arabic (MSA), particularly in settings where punctuation is inconsistent, missing, or noisy.
AraSeg contains manually annotated documents collected from diverse sources and genres, enabling robust evaluation across different writing styles and domains.

AraSeg-PA is the Paragraph-Aware (PA) variant of the corpus where documents include paragraph boundaries and punctuation marks.

---
## Dataset Structure

### Data Instances
```
{'doc_id': 'doc_00b450a96684',
'tokens': ['الفصل','الأول','حين','ركبت','السيارة','لم','أكن','أتصور','أنني','أبدأ', ...],
'labels': [0, 1, 0, 0, 0, 0, 0, 0, 0, 0, ...],
'text': 'أبدأ الفصل الأول حين ركبت السيارة لم أكن أتصور أنني...',
'label_str': '0100000000...'}
```


### Data Fields
- **doc_id**: Unique document identifier.
- **tokens**: White-space-tokenized document represented as a list of tokens.
- **labels**: Token-level sentence boundary labels. `1` indicates that a sentence boundary follows the current token, while `0` indicates no boundary.
- **text**: Document.
- **label_str**: Sentence boundary labels as a binary string. `1` indicates that a sentence boundary follows the current token, while `0` indicates no boundary.

### Data Splits
- **train**: 174 documents (10,657 sentences and 128K words).
- **dev**: 222 documents (12,985 sentences and 164K words).
- **test**: 262 documents (12,509 sentences and 159K words).
---
## Task Definition
Sentence segmentation is formulated as a binary token classification task. 

Given a sequence of tokens: ```[token_1, token_2, ..., token_n]```, the model predicts for each token whether a sentence boundary follows it.
For example:

| Token | Label |
|---|---|
| ذهب | 0 |
| الطالب | 0 |
| إلى | 0 |
| المدرسة | 1 |

The label `1` indicates that the sentence ends after the token.

---

## Evaluation
We evaluate systems using boundary-level metrics:

- **Boundary Precision (P):** Percentage of predicted sentence boundaries that are correct.
- **Boundary Recall (R):** Percentage of gold sentence boundaries correctly identified.
- **Boundary F1 (F1):** Harmonic mean of precision and recall.
  
Metrics are computed at the document level and averaged across the corpus.

We provide evaluation scripts on this [repo](https://github.com/mbzuai-nlp/araseg-shared-task-2026).

---