---
license: cc-by-sa-4.0
language:
- tr
pretty_name: Turkish Stopword Lists (static, dynamic, hybrid)
tags:
- stopwords
- turkish
size_categories:
- 100K<n<1M
viewer: false
---

# Turkish Stopword Lists

Part of a Turkish text preprocessing toolkit built for CMPE 561 (Natural Language Processing), Application Project 1, Boğaziçi University, 2026. All code is our own; no external NLP library is used in the systems. Status: progress report, 20 October 2026.

General-domain Turkish stopword lists built three ways, as the assignment requires: a **static** list curated from
an existing resource, a **dynamic** list extracted from corpus statistics, and their **hybrid** union. Companion
repositories: [normalization](https://huggingface.co/datasets/eminesener/normalization),
[sentence_splitter](https://huggingface.co/datasets/eminesener/sentence_splitter).

At run time a stopword is removed when its Turkish-lowercased form is in the chosen list. Hybrid = static ∪ dynamic
(797 words).

## Files

| File | Format | Contents |
|---|---|---|
| `lists/stopwords_static_expanded.txt` | one word per line | **static list, 686 words**: stopwords-iso repaired (37 mis-encoded entries), 31 entries removed (8 content words, 23 number words), + 223 inflected forms and the question-particle paradigm, + 23 closed-class additions |
| `lists/stopwords_static.txt` | one word per line | intermediate cleaned list, 440 words |
| `lists/stopwords_dynamic.txt` | one word per line | **dynamic list, 200 words**: Wikipedia + news, worst-rank combination, Poisson measure, k chosen on dev |
| `curation/stopwords_static_exclusions.tsv` | `word ⇥ reason` | every removed entry with its reason |
| `curation/stopword_inflections.tsv` | `lemma ⇥ forms` | inflected forms of 24 function words (hand-written from Turkish grammar) |
| `curation/stopwords_static_additions.tsv` | `word ⇥ rule ⇥ note` | 23 added closed-class words (rules D23/D24) |
| `guidelines/GUIDELINES.md` | Markdown | our stopword definition and annotation rules D2–D27 |
| `rankings/wikipedia/ranked_<measure>.tsv` | `term ⇥ score` | full rankings of 581,412 word types from a 20,000-article Wikipedia sample by term frequency, document frequency, entropy and a Poisson score |
| `results/` | JSON, Markdown | all dev/test scores, static-list ablation, per-genre scores, error analysis, Jaccard distances, corpus statistics |
| `figures/` | PNG | test comparison, static list step by step, dynamic vs. static, threshold curves, Zipf plot, flow diagrams (titles in Turkish) |

Lines starting with `#` in the list files are provenance comments. The news rankings are not included because the
news corpus has no stated licence.

## Results (test, provisional)

| System | Size | P | R | F1 | Acc |
|---|---|---|---|---|---|
| NLTK | 53 | 97.6 | 43.7 | 60.3 | 84.4 |
| Can et al. 2008 | 147 | 95.8 | 71.8 | 82.1 | 91.5 |
| Lucene | 209 | 91.8 | 74.6 | 82.3 | 91.3 |
| stopwords-iso (raw) | 504 | 88.8 | 81.3 | 84.9 | 92.2 |
| **Static (ours)** | 686 | 93.0 | 89.4 | **91.2** | **95.3** |
| Dynamic (ours) | 200 | 75.9 | 68.7 | 72.1 | 85.6 |
| Hybrid (ours) | 797 | 78.4 | 90.5 | 84.0 | 90.6 |

Evaluation is token-level on 100 + 100 sentences of UD Turkish-BOUN dev/test (20 per genre; 952 / 1,045 word tokens),
positive class = stopword. **The reference labels were revised by an LLM (Claude, Anthropic) following
`GUIDELINES.md` and are awaiting human review**; all scores are provisional, and the reference files will be added
after the review.

## Sources

| Source | Licence | Use |
|---|---|---|
| stopwords-iso Turkish ([stopwords-iso/stopwords-tr](https://github.com/stopwords-iso/stopwords-tr)) | MIT | base of the static list |
| NLTK ([nltk/nltk_data](https://github.com/nltk/nltk_data)), Lucene ([apache/lucene](https://github.com/apache/lucene)), spaCy ([explosion/spaCy](https://github.com/explosion/spaCy)), trstop ([uzay00/trstop](https://github.com/uzay00/trstop)), Can et al. 2008 (JASIST 59(3)) | Apache 2.0 / Apache 2.0 / MIT / MIT / article | comparison only, not included |
| Turkish Wikipedia, dump 20231101 ([wikimedia/wikipedia](https://huggingface.co/datasets/wikimedia/wikipedia), `20231101.tr`) | CC BY-SA 3.0 / GFDL | dynamic extraction (20,000-article sample, seed 13) |
| TTC-4900 news ([savasy/ttc4900](https://huggingface.co/datasets/savasy/ttc4900)); Yıldırım & Yıldız 2018 | not stated; not redistributed | second corpus for the cross-corpus filter |
| UD Turkish-BOUN ([UniversalDependencies/UD_Turkish-BOUN](https://github.com/UniversalDependencies/UD_Turkish-BOUN)) | CC BY-SA 4.0 | reference sentences |

## Main literature

Nothman, Qin & Yurchak 2018 (NLP-OSS); Can et al. 2008 (JASIST); Saif et al. 2014 (LREC); Sarica & Luo 2021
(PLOS ONE); Schofield, Magnusson & Mimno 2017 (EACL); Fan, Arora & Treude 2023 (NLBSE).