language: kab
language_name: Kabyle
language_family: berber
tags:
- wikilangs
- nlp
- tokenizer
- embeddings
- n-gram
- markov
- wikipedia
- feature-extraction
- sentence-similarity
- tokenization
- n-grams
- markov-chain
- text-mining
- fasttext
- babelvec
- vocabulous
- vocabulary
- monolingual
- family-berber
license: mit
library_name: wikilangs
pipeline_tag: text-generation
datasets:
- omarkamali/wikipedia-monthly
dataset_info:
name: wikipedia-monthly
description: Monthly snapshots of Wikipedia articles across 300+ languages
metrics:
- name: best_compression_ratio
type: compression
value: 3.787
- name: best_isotropy
type: isotropy
value: 0.8059
- name: vocabulary_size
type: vocab
value: 0
generated: 2026-01-10T00:00:00.000Z
Kabyle - Wikilangs Models
Comprehensive Research Report & Full Ablation Study
This repository contains NLP models trained and evaluated by Wikilangs, specifically on Kabyle Wikipedia data. We analyze tokenizers, n-gram models, Markov chains, vocabulary statistics, and word embeddings.
📋 Repository Contents
Models & Assets
- Tokenizers (8k, 16k, 32k, 64k)
- N-gram models (2, 3, 4, 5-gram)
- Markov chains (context of 1, 2, 3, 4 and 5)
- Subword N-gram and Markov chains
- Embeddings in various sizes and dimensions (aligned and unaligned)
- Language Vocabulary
- Language Statistics
Analysis and Evaluation
- 1. Tokenizer Evaluation
- 2. N-gram Model Evaluation
- 3. Markov Chain Evaluation
- 4. Vocabulary Analysis
- 5. Word Embeddings Evaluation
- 6. Morphological Analysis (Experimental)
- 7. Summary & Recommendations
- Metrics Glossary
- Visualizations Index
1. Tokenizer Evaluation
Results
| Vocab Size | Compression | Avg Token Len | UNK Rate | Total Tokens |
|---|---|---|---|---|
| 8k | 3.109x | 3.11 | 0.1037% | 513,076 |
| 16k | 3.378x | 3.38 | 0.1127% | 472,257 |
| 32k | 3.612x | 3.62 | 0.1205% | 441,659 |
| 64k | 3.787x 🏆 | 3.79 | 0.1263% | 421,278 |
Tokenization Examples
Below are sample sentences tokenized with each vocabulary size:
Sample 1: Ho Chi Minh City — Tamanaɣt n tmurt n Dong Nam Bo, Vietnam. Tettwassen s isem n ...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | ▁ho ▁chi ▁min h ▁city ▁— ▁tamanaɣt ▁n ▁tmurt ▁n ... (+18 more) |
28 |
| 16k | ▁ho ▁chi ▁minh ▁city ▁— ▁tamanaɣt ▁n ▁tmurt ▁n ▁d ... (+17 more) |
27 |
| 32k | ▁ho ▁chi ▁minh ▁city ▁— ▁tamanaɣt ▁n ▁tmurt ▁n ▁dong ... (+14 more) |
24 |
| 64k | ▁ho ▁chi ▁minh ▁city ▁— ▁tamanaɣt ▁n ▁tmurt ▁n ▁dong ... (+13 more) |
23 |
Sample 2: Montargis d tamdint n Fransa. D tamaneɣt n agezdu (département) n Loiret. Zedɣen...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | ▁mont arg is ▁d ▁tamdint ▁n ▁fransa . ▁d ▁tamaneɣt ... (+18 more) |
28 |
| 16k | ▁mont arg is ▁d ▁tamdint ▁n ▁fransa . ▁d ▁tamaneɣt ... (+17 more) |
27 |
| 32k | ▁mont argis ▁d ▁tamdint ▁n ▁fransa . ▁d ▁tamaneɣt ▁n ... (+15 more) |
25 |
| 64k | ▁mont argis ▁d ▁tamdint ▁n ▁fransa . ▁d ▁tamaneɣt ▁n ... (+15 more) |
25 |
Sample 3: Oregon d yiwen seg Yiwunak Yeddukklen. Tajumma-nnes 255.026 km2. Zedɣen-t 2.241....
| Vocab | Tokens | Count |
|---|---|---|
| 8k | ▁or eg on ▁d ▁yiwen ▁seg ▁yiwunak ▁yeddukklen . ▁tajumma ... (+36 more) |
46 |
| 16k | ▁or eg on ▁d ▁yiwen ▁seg ▁yiwunak ▁yeddukklen . ▁tajumma ... (+36 more) |
46 |
| 32k | ▁oregon ▁d ▁yiwen ▁seg ▁yiwunak ▁yeddukklen . ▁tajumma - nnes ... (+34 more) |
44 |
| 64k | ▁oregon ▁d ▁yiwen ▁seg ▁yiwunak ▁yeddukklen . ▁tajumma - nnes ... (+34 more) |
44 |
Key Findings
- Best Compression: 64k achieves 3.787x compression
- Lowest UNK Rate: 8k with 0.1037% unknown tokens
- Trade-off: Larger vocabularies improve compression but increase model size
- Recommendation: 32k vocabulary provides optimal balance for production use
2. N-gram Model Evaluation
Results
| N-gram | Variant | Perplexity | Entropy | Unique N-grams | Top-100 Coverage | Top-1000 Coverage |
|---|---|---|---|---|---|---|
| 2-gram | Word | 7,571 | 12.89 | 19,430 | 16.5% | 43.3% |
| 2-gram | Subword | 303 🏆 | 8.25 | 3,654 | 66.0% | 98.4% |
| 3-gram | Word | 11,108 | 13.44 | 22,206 | 13.3% | 34.1% |
| 3-gram | Subword | 2,694 | 11.40 | 25,828 | 26.3% | 66.9% |
| 4-gram | Word | 19,522 | 14.25 | 32,796 | 10.1% | 25.2% |
| 4-gram | Subword | 15,004 | 13.87 | 120,516 | 12.4% | 38.1% |
| 5-gram | Word | 11,855 | 13.53 | 19,714 | 12.9% | 29.9% |
| 5-gram | Subword | 48,269 | 15.56 | 267,598 | 7.1% | 23.6% |
Top 5 N-grams by Size
2-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | i d |
3,560 |
| 2 | kra n |
1,303 |
| 3 | tmurt n |
1,292 |
| 4 | yiwet n |
1,270 |
| 5 | twilayt n |
1,230 |
3-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | n twilayt n |
1,040 |
| 2 | deg useggas n |
826 |
| 3 | isem is s |
557 |
| 4 | is nniḍen s |
543 |
| 5 | ismawen is nniḍen |
542 |
4-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | ismawen is nniḍen s |
542 |
| 2 | taɣiwant n twilayt n |
284 |
| 3 | is nniḍen s teqbaylit |
272 |
| 4 | isem is s latinit |
272 |
| 5 | isem is s tefransist |
272 |
5-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | ismawen is nniḍen s teqbaylit |
272 |
| 2 | ismawen is nniḍen s tmaziɣt |
270 |
| 3 | ismawen isem is s latinit |
264 |
| 4 | d taɣiwant n twilayt n |
263 |
| 5 | is nniḍen s tmaziɣt isseqdac |
254 |
2-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | n _ |
184,557 |
| 2 | _ t |
121,740 |
| 3 | e n |
95,979 |
| 4 | _ a |
93,884 |
| 5 | _ n |
91,808 |
3-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ n _ |
77,599 |
| 2 | e n _ |
58,304 |
| 3 | _ t a |
38,861 |
| 4 | _ d _ |
35,833 |
| 5 | n _ t |
32,724 |
4-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ n _ t |
23,561 |
| 2 | _ d e g |
22,211 |
| 3 | d e g _ |
21,956 |
| 4 | t _ n _ |
18,573 |
| 5 | n _ n _ |
13,088 |
5-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ d e g _ |
21,039 |
| 2 | _ n _ y i |
7,349 |
| 3 | d e g _ t |
6,497 |
| 4 | t _ n _ t |
6,453 |
| 5 | e n _ n _ |
6,375 |
Key Findings
- Best Perplexity: 2-gram (subword) with 303
- Entropy Trend: Decreases with larger n-grams (more predictable)
- Coverage: Top-1000 patterns cover ~24% of corpus
- Recommendation: 4-gram or 5-gram for best predictive performance
3. Markov Chain Evaluation
Results
| Context | Variant | Avg Entropy | Perplexity | Branching Factor | Unique Contexts | Predictability |
|---|---|---|---|---|---|---|
| 1 | Word | 0.6846 | 1.607 | 4.33 | 96,821 | 31.5% |
| 1 | Subword | 1.1181 | 2.171 | 8.37 | 1,137 | 0.0% |
| 2 | Word | 0.2442 | 1.184 | 1.61 | 417,535 | 75.6% |
| 2 | Subword | 0.9627 | 1.949 | 5.62 | 9,513 | 3.7% |
| 3 | Word | 0.0844 | 1.060 | 1.15 | 667,894 | 91.6% |
| 3 | Subword | 0.8237 | 1.770 | 4.02 | 53,433 | 17.6% |
| 4 | Word | 0.0286 🏆 | 1.020 | 1.04 | 763,067 | 97.1% |
| 4 | Subword | 0.6223 | 1.539 | 2.65 | 214,801 | 37.8% |
Generated Text Samples (Word-based)
Below are text samples generated from each word-based Markov chain model:
Context Size 1:
n tewsit a u ad snernin tamusni iǧaḥ dayen aɛyiɣ baṛka yi ddunit akken ad kecmentd yifrax seld tama akaɣeḍ ssenṭaḍen t yettwalin dakk n medden semman askasi ɣef leḥsab ndeg ddaw yifassen yessedras yessenqas seg teftist n yimɣan yeǧǧuǧǧugen taẓrigt tamezwarut i lmend n ...
Context Size 2:
i d yuran dyujin layirs d 81 tinfaliyin tivaṭikaniyin ffɣent d aṭas n tamerrit deg tagzirt akra n wakud ma yella idles afr ensis yeǧhed yeffeɣ i tlisa n snat n tamiwin atmurt n rusya aseggas n dɣa gan d arraw n yakuf di tsut tis 7 aẓaṛ nsen
Context Size 3:
n twilayt n wehran zedɣen tt 6 800 n yimezdaɣen n batnetdeg useggas n yettwaḥsab azal n 2 600 000 n yimezdaɣen di singapur gar asen 60 d imaliziyenisem is s tefransist genêt pas de nom spécifique genista tricuspidatatazeggart n weɣyulgenêt pas de ...
Context Size 4:
ismawen is nniḍen s teqbaylit ismawen is nniḍen s tmaziɣt isseqdac tiwelhiwin imeɣlalen n tizzegzuttaɣiwant n twilayt n tmenɣest zedɣen tt 28 022 n yimezdaɣen tamdint a d tin aydeg d zgant tmuraisem is s tefransist genêt purgatif ulac isem is s tefṛansist ismawen is nniḍen s teqbaylit ismawen ...
Generated Text Samples (Subword-based)
Below are text samples generated from each subword-based Markov chain model:
Context Size 1:
_zir_wayalluntawami_a_4_d_t_ad_metinan_1_an_awek
Context Size 2:
n_ualekcemniyezme_tmaztionittes-teen_walt_yel_amen_
Context Size 3:
_n_n_wassnes_clin,en_deg_160_n_macaf_tasuqi,_neɣ_s_asw
Context Size 4:
_n_taggar_n_lignett_deg_zik_(aqqaṛen_ndeg_unit_i_d-yeqqam
Key Findings
- Best Predictability: Context-4 (word) with 97.1% predictability
- Branching Factor: Decreases with context size (more deterministic)
- Memory Trade-off: Larger contexts require more storage (214,801 contexts)
- Recommendation: Context-3 or Context-4 for text generation
4. Vocabulary Analysis
Statistics
| Metric | Value |
|---|---|
| Vocabulary Size | 38,216 |
| Total Tokens | 801,998 |
| Mean Frequency | 20.99 |
| Median Frequency | 3 |
| Frequency Std Dev | 517.14 |
Most Common Words
| Rank | Word | Frequency |
|---|---|---|
| 1 | n | 78,490 |
| 2 | d | 50,398 |
| 3 | deg | 22,375 |
| 4 | s | 15,955 |
| 5 | i | 14,664 |
| 6 | ad | 9,209 |
| 7 | is | 7,643 |
| 8 | di | 6,332 |
| 9 | seg | 5,286 |
| 10 | a | 5,100 |
Least Common Words (from vocabulary)
| Rank | Word | Frequency |
|---|---|---|
| 1 | eskil | 2 |
| 2 | tatinawit | 2 |
| 3 | tahelinistit | 2 |
| 4 | tigrigiyin | 2 |
| 5 | yimensiyen | 2 |
| 6 | tychy | 2 |
| 7 | abarṭinun | 2 |
| 8 | parthenos | 2 |
| 9 | nḥerrem | 2 |
| 10 | ubani | 2 |
Zipf's Law Analysis
| Metric | Value |
|---|---|
| Zipf Coefficient | 1.0302 |
| R² (Goodness of Fit) | 0.997642 |
| Adherence Quality | excellent |
Coverage Analysis
| Top N Words | Coverage |
|---|---|
| Top 100 | 44.1% |
| Top 1,000 | 66.9% |
| Top 5,000 | 82.8% |
| Top 10,000 | 89.1% |
Key Findings
- Zipf Compliance: R²=0.9976 indicates excellent adherence to Zipf's law
- High Frequency Dominance: Top 100 words cover 44.1% of corpus
- Long Tail: 28,216 words needed for remaining 10.9% coverage
5. Word Embeddings Evaluation
5.1 Cross-Lingual Alignment
5.2 Model Comparison
| Model | Dimension | Isotropy | Semantic Density | Alignment R@1 | Alignment R@10 |
|---|---|---|---|---|---|
| mono_32d | 32 | 0.8059 🏆 | 0.3140 | N/A | N/A |
| mono_64d | 64 | 0.5286 | 0.2866 | N/A | N/A |
| mono_128d | 128 | 0.1321 | 0.2758 | N/A | N/A |
| aligned_32d | 32 | 0.8059 | 0.3266 | 0.0200 | 0.2100 |
| aligned_64d | 64 | 0.5286 | 0.2915 | 0.0480 | 0.2920 |
| aligned_128d | 128 | 0.1321 | 0.2848 | 0.0780 | 0.3160 |
Key Findings
- Best Isotropy: mono_32d with 0.8059 (more uniform distribution)
- Semantic Density: Average pairwise similarity of 0.2965. Lower values indicate better semantic separation.
- Alignment Quality: Aligned models achieve up to 7.8% R@1 in cross-lingual retrieval.
- Recommendation: 128d aligned for best cross-lingual performance
6. Morphological Analysis (Experimental)
This section presents an automated morphological analysis derived from the statistical divergence between word-level and subword-level models. By analyzing where subword predictability spikes and where word-level coverage fails, we can infer linguistic structures without supervised data.
6.1 Productivity & Complexity
| Metric | Value | Interpretation | Recommendation |
|---|---|---|---|
| Productivity Index | 5.000 | High morphological productivity | Reliable analysis |
| Idiomaticity Gap | 0.266 | High formulaic/idiomatic content | - |
6.2 Affix Inventory (Productive Units)
These are the most productive prefixes and suffixes identified by sampling the vocabulary for global substitutability patterns. A unit is considered an affix if stripping it leaves a valid stem that appears in other contexts.
Productive Prefixes
| Prefix | Examples |
|---|---|
-t |
timesrifgin, tribulus, teqbilt |
-a |
anmezray, abruri, achieving |
-ta |
taɣerdemmuct, tagi, tanefrant |
-i |
idris, inigan, imuhaɣ |
-ti |
timesrifgin, timenzimawen, tilellit |
-te |
teqbilt, teẓẓun, texḍa |
-u |
umdafar, uzawag, udfel |
-ye |
yebbwi, yeksan, yewala |
Productive Suffixes
| Suffix | Examples |
|---|---|
-n |
timesrifgin, yeksan, ḥulfun |
-en |
yikatalanen, ttɛeddayen, yḍemɛen |
-t |
ssekrent, teqbilt, taɣerdemmuct |
-s |
tribulus, idris, wegnes |
-a |
daïra, susṭara, waqila |
-in |
timesrifgin, tebɣin, tiznasin |
-e |
odense, brise, gustave |
-r |
umdafar, muɣrar, neuer |
6.3 Bound Stems (Lexical Roots)
Bound stems are high-frequency subword units that are semantically cohesive but rarely appear as standalone words. These often correspond to the 'core' of a word that requires inflection or derivation to be valid.
| Stem | Cohesion | Substitutability | Examples |
|---|---|---|---|
etta |
1.75x | 102 contexts | setta, netta, tettaf |
ttwa |
1.80x | 70 contexts | ittwa, attwaɣ, uttwaɣ |
aren |
1.82x | 48 contexts | raren, qaren, karen |
anen |
1.98x | 31 contexts | ranen, banen, ibanen |
elli |
1.42x | 95 contexts | nelli, zelli, belli |
tame |
1.90x | 28 contexts | tameṭ, tamet, tamelt |
egga |
1.46x | 79 contexts | yegga, tegga, teggar |
mazi |
1.79x | 27 contexts | mazis, amazi, maziɣ |
ettw |
2.07x | 15 contexts | yettwaɣ, tettwaɣ, yettweg |
segg |
1.76x | 23 contexts | usegg, aseggi, seggas |
zdaɣ |
2.02x | 13 contexts | imzdaɣ, tezdaɣ, yezdaɣ |
ezda |
1.53x | 31 contexts | tezdaɣ, yezdaɣ, wezdam |
6.4 Affix Compatibility (Co-occurrence)
This table shows which prefixes and suffixes most frequently co-occur on the same stems, revealing the 'stacking' rules of the language's morphology.
| Prefix | Suffix | Frequency | Examples |
|---|---|---|---|
-t |
-t |
744 words | tamattant, tḥandast |
-i |
-n |
510 words | iɣiren, izegriren |
-i |
-en |
474 words | iɣiren, izegriren |
-t |
-n |
441 words | tedqiqin, tibankiwin |
-t |
-in |
347 words | tedqiqin, tibankiwin |
-y |
-n |
170 words | yinmezrayen, yimdebbṛen |
-ye |
-n |
164 words | yemxallafen, yettwakten |
-y |
-en |
151 words | yinmezrayen, yimdebbṛen |
-ye |
-en |
132 words | yemxallafen, yettwakten |
-t |
-a |
127 words | tsuda, takma |
6.5 Recursive Morpheme Segmentation
Using Recursive Hierarchical Substitutability, we decompose complex words into their constituent morphemes. This approach handles nested affixes (e.g., prefix-prefix-root-suffix).
| Word | Suggested Split | Confidence | Stem |
|---|---|---|---|
| populations | populatio-n-s |
7.5 | n |
| americanus | america-n-us |
7.5 | n |
| ttɛawanen | ttɛawa-n-en |
7.5 | n |
| yinyutrunen | yinyutru-n-en |
7.5 | n |
| tkebbanin | tkebba-n-in |
7.5 | n |
| conclusions | conclusio-n-s |
7.5 | n |
| constantine | constanti-n-e |
7.5 | n |
| iwezlanen | iwezla-n-en |
7.5 | n |
| isemrasen | isemra-s-en |
7.5 | s |
| ticebḥanin | ticebḥ-an-in |
7.5 | an |
| uctavyanus | uctavya-n-us |
7.5 | n |
| iwindalen | iwind-al-en |
7.5 | al |
| oudjidane | oudjida-n-e |
7.5 | n |
| isbegsanen | isbegsa-n-en |
7.5 | n |
| tisinsinin | tisinsi-n-in |
7.5 | n |
6.6 Linguistic Interpretation
Automated Insight: The language Kabyle shows high morphological productivity. The subword models are significantly more efficient than word models, suggesting a rich system of affixation or compounding.
Note on Idiomaticity: The high Idiomaticity Gap suggests a large number of frequent multi-word expressions or formulaic sequences that are statistically distinct from their component parts.
7. Summary & Recommendations
Production Recommendations
| Component | Recommended | Rationale |
|---|---|---|
| Tokenizer | 64k BPE | Best compression (3.79x) |
| N-gram | 2-gram | Lowest perplexity (303) |
| Markov | Context-4 | Highest predictability (97.1%) |
| Embeddings | 100d | Balanced semantic capture and isotropy |
Appendix: Metrics Glossary & Interpretation Guide
This section provides definitions, intuitions, and guidance for interpreting the metrics used throughout this report.
Tokenizer Metrics
Compression Ratio
Definition: The ratio of characters to tokens (chars/token). Measures how efficiently the tokenizer represents text.
Intuition: Higher compression means fewer tokens needed to represent the same text, reducing sequence lengths for downstream models. A 3x compression means ~3 characters per token on average.
What to seek: Higher is generally better for efficiency, but extremely high compression may indicate overly aggressive merging that loses morphological information.
Average Token Length (Fertility)
Definition: Mean number of characters per token produced by the tokenizer.
Intuition: Reflects the granularity of tokenization. Longer tokens capture more context but may struggle with rare words; shorter tokens are more flexible but increase sequence length.
What to seek: Balance between 2-5 characters for most languages. Arabic/morphologically-rich languages may benefit from slightly longer tokens.
Unknown Token Rate (OOV Rate)
Definition: Percentage of tokens that map to the unknown/UNK token, indicating words the tokenizer cannot represent.
Intuition: Lower OOV means better vocabulary coverage. High OOV indicates the tokenizer encounters many unseen character sequences.
What to seek: Below 1% is excellent; below 5% is acceptable. BPE tokenizers typically achieve very low OOV due to subword fallback.
N-gram Model Metrics
Perplexity
Definition: Measures how "surprised" the model is by test data. Mathematically: 2^(cross-entropy). Lower values indicate better prediction.
Intuition: If perplexity is 100, the model is as uncertain as if choosing uniformly among 100 options at each step. A perplexity of 10 means effectively choosing among 10 equally likely options.
What to seek: Lower is better. Perplexity decreases with larger n-grams (more context). Values vary widely by language and corpus size.
Entropy
Definition: Average information content (in bits) needed to encode the next token given the context. Related to perplexity: perplexity = 2^entropy.
Intuition: High entropy means high uncertainty/randomness; low entropy means predictable patterns. Natural language typically has entropy between 1-4 bits per character.
What to seek: Lower entropy indicates more predictable text patterns. Entropy should decrease as n-gram size increases.
Coverage (Top-K)
Definition: Percentage of corpus occurrences explained by the top K most frequent n-grams.
Intuition: High coverage with few patterns indicates repetitive/formulaic text; low coverage suggests diverse vocabulary usage.
What to seek: Depends on use case. For language modeling, moderate coverage (40-60% with top-1000) is typical for natural text.
Markov Chain Metrics
Average Entropy
Definition: Mean entropy across all contexts, measuring average uncertainty in next-word prediction.
Intuition: Lower entropy means the model is more confident about what comes next. Context-1 has high entropy (many possible next words); Context-4 has low entropy (few likely continuations).
What to seek: Decreasing entropy with larger context sizes. Very low entropy (<0.1) indicates highly deterministic transitions.
Branching Factor
Definition: Average number of unique next tokens observed for each context.
Intuition: High branching = many possible continuations (flexible but uncertain); low branching = few options (predictable but potentially repetitive).
What to seek: Branching factor should decrease with context size. Values near 1.0 indicate nearly deterministic chains.
Predictability
Definition: Derived metric: (1 - normalized_entropy) × 100%. Indicates how deterministic the model's predictions are.
Intuition: 100% predictability means the next word is always certain; 0% means completely random. Real text falls between these extremes.
What to seek: Higher predictability for text generation quality, but too high (>98%) may produce repetitive output.
Vocabulary & Zipf's Law Metrics
Zipf's Coefficient
Definition: The slope of the log-log plot of word frequency vs. rank. Zipf's law predicts this should be approximately -1.
Intuition: A coefficient near -1 indicates the corpus follows natural language patterns where a few words are very common and most words are rare.
What to seek: Values between -0.8 and -1.2 indicate healthy natural language distribution. Deviations may suggest domain-specific or artificial text.
R² (Coefficient of Determination)
Definition: Measures how well the linear fit explains the frequency-rank relationship. Ranges from 0 to 1.
Intuition: R² near 1.0 means the data closely follows Zipf's law; lower values indicate deviation from expected word frequency patterns.
What to seek: R² > 0.95 is excellent; > 0.99 indicates near-perfect Zipf adherence typical of large natural corpora.
Vocabulary Coverage
Definition: Cumulative percentage of corpus tokens accounted for by the top N words.
Intuition: Shows how concentrated word usage is. If top-100 words cover 50% of text, the corpus relies heavily on common words.
What to seek: Top-100 covering 30-50% is typical. Higher coverage indicates more repetitive text; lower suggests richer vocabulary.
Word Embedding Metrics
Isotropy
Definition: Measures how uniformly distributed vectors are in the embedding space. Computed as the ratio of minimum to maximum singular values.
Intuition: High isotropy (near 1.0) means vectors spread evenly in all directions; low isotropy means vectors cluster in certain directions, reducing expressiveness.
What to seek: Higher isotropy generally indicates better-quality embeddings. Values > 0.1 are reasonable; > 0.3 is good. Lower-dimensional embeddings tend to have higher isotropy.
Average Norm
Definition: Mean magnitude (L2 norm) of word vectors in the embedding space.
Intuition: Indicates the typical "length" of vectors. Consistent norms suggest stable training; high variance may indicate some words are undertrained.
What to seek: Relatively consistent norms across models. The absolute value matters less than consistency (low std deviation).
Cosine Similarity
Definition: Measures angular similarity between vectors, ranging from -1 (opposite) to 1 (identical direction).
Intuition: Words with similar meanings should have high cosine similarity. This is the standard metric for semantic relatedness in embeddings.
What to seek: Semantically related words should score > 0.5; unrelated words should be near 0. Synonyms often score > 0.7.
t-SNE Visualization
Definition: t-Distributed Stochastic Neighbor Embedding - a dimensionality reduction technique that preserves local structure for visualization.
Intuition: Clusters in t-SNE plots indicate groups of semantically related words. Spread indicates vocabulary diversity; tight clusters suggest semantic coherence.
What to seek: Meaningful clusters (e.g., numbers together, verbs together). Avoid over-interpreting distances - t-SNE preserves local, not global, structure.
General Interpretation Guidelines
- Compare within model families: Metrics are most meaningful when comparing models of the same type (e.g., 8k vs 64k tokenizer).
- Consider trade-offs: Better performance on one metric often comes at the cost of another (e.g., compression vs. OOV rate).
- Context matters: Optimal values depend on downstream tasks. Text generation may prioritize different metrics than classification.
- Corpus influence: All metrics are influenced by corpus characteristics. Wikipedia text differs from social media or literature.
- Language-specific patterns: Morphologically rich languages (like Arabic) may show different optimal ranges than analytic languages.
Visualizations Index
| Visualization | Description |
|---|---|
| Tokenizer Compression | Compression ratios by vocabulary size |
| Tokenizer Fertility | Average token length by vocabulary |
| Tokenizer OOV | Unknown token rates |
| Tokenizer Total Tokens | Total tokens by vocabulary |
| N-gram Perplexity | Perplexity by n-gram size |
| N-gram Entropy | Entropy by n-gram size |
| N-gram Coverage | Top pattern coverage |
| N-gram Unique | Unique n-gram counts |
| Markov Entropy | Entropy by context size |
| Markov Branching | Branching factor by context |
| Markov Contexts | Unique context counts |
| Zipf's Law | Frequency-rank distribution with fit |
| Vocab Frequency | Word frequency distribution |
| Top 20 Words | Most frequent words |
| Vocab Coverage | Cumulative coverage curve |
| Embedding Isotropy | Vector space uniformity |
| Embedding Norms | Vector magnitude distribution |
| Embedding Similarity | Word similarity heatmap |
| Nearest Neighbors | Similar words for key terms |
| t-SNE Words | 2D word embedding visualization |
| t-SNE Sentences | 2D sentence embedding visualization |
| Position Encoding | Encoding method comparison |
| Model Sizes | Storage requirements |
| Performance Dashboard | Comprehensive performance overview |
About This Project
Data Source
Models trained on wikipedia-monthly - a monthly snapshot of Wikipedia articles across 300+ languages.
Project
A project by Wikilangs - Open-source NLP models for every Wikipedia language.
Maintainer
Citation
If you use these models in your research, please cite:
@misc{wikilangs2025,
author = {Kamali, Omar},
title = {Wikilangs: Open NLP Models for Wikipedia Languages},
year = {2025},
doi = {10.5281/zenodo.18073153},
publisher = {Zenodo},
url = {https://huggingface.co/wikilangs}
institution = {Omneity Labs}
}
License
MIT License - Free for academic and commercial use.
Links
- 🌐 Website: wikilangs.org
- 🤗 Models: huggingface.co/wikilangs
- 📊 Data: wikipedia-monthly
- 👤 Author: Omar Kamali
- 🤝 Sponsor: Featherless AI
Generated by Wikilangs Models Pipeline
Report Date: 2026-01-10 07:12:49



















