Turkmen - Wikilangs Models
Comprehensive Research Report & Full Ablation Study
This repository contains NLP models trained and evaluated by Wikilangs, specifically on Turkmen Wikipedia data. We analyze tokenizers, n-gram models, Markov chains, vocabulary statistics, and word embeddings.
π 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 | 3.867x | 3.87 | 0.1563% | 394,866 |
| 16k | 4.295x | 4.30 | 0.1736% | 355,501 |
| 32k | 4.665x | 4.67 | 0.1885% | 327,292 |
| 64k | 4.949x π | 4.95 | 0.2000% | 308,505 |
Tokenization Examples
Below are sample sentences tokenized with each vocabulary size:
Sample 1: Wakalar Sebitler boΓ½unΓ§a Tema boΓ½unΓ§a <noinclude> DΓΌnΓ½Γ€ inenler Aradan Γ§ykanlar
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βwakalar βsebitler βboΓ½unΓ§a βtema βboΓ½unΓ§a β< noinclude > βdΓΌnΓ½Γ€ βinenler ... (+2 more) |
12 |
| 16k | βwakalar βsebitler βboΓ½unΓ§a βtema βboΓ½unΓ§a β< noinclude > βdΓΌnΓ½Γ€ βinenler ... (+2 more) |
12 |
| 32k | βwakalar βsebitler βboΓ½unΓ§a βtema βboΓ½unΓ§a β< noinclude > βdΓΌnΓ½Γ€ βinenler ... (+2 more) |
12 |
| 64k | βwakalar βsebitler βboΓ½unΓ§a βtema βboΓ½unΓ§a β< noinclude > βdΓΌnΓ½Γ€ βinenler ... (+2 more) |
12 |
Sample 2: Wakalar Sebitler boΓ½unΓ§a Tema boΓ½unΓ§a <noinclude> DΓΌnΓ½Γ€ inenler Aradan Γ§ykanlar
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βwakalar βsebitler βboΓ½unΓ§a βtema βboΓ½unΓ§a β< noinclude > βdΓΌnΓ½Γ€ βinenler ... (+2 more) |
12 |
| 16k | βwakalar βsebitler βboΓ½unΓ§a βtema βboΓ½unΓ§a β< noinclude > βdΓΌnΓ½Γ€ βinenler ... (+2 more) |
12 |
| 32k | βwakalar βsebitler βboΓ½unΓ§a βtema βboΓ½unΓ§a β< noinclude > βdΓΌnΓ½Γ€ βinenler ... (+2 more) |
12 |
| 64k | βwakalar βsebitler βboΓ½unΓ§a βtema βboΓ½unΓ§a β< noinclude > βdΓΌnΓ½Γ€ βinenler ... (+2 more) |
12 |
Sample 3: SeΓ½di etraby β Lebap welayatynyΕ bir etrabydyr. etraplary welaΓ½aty welaΓ½atyndaky...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βseΓ½ di βetraby ββ βlebap βwelayat ynyΕ βbir βetraby dyr ... (+5 more) |
15 |
| 16k | βseΓ½di βetraby ββ βlebap βwelayat ynyΕ βbir βetraby dyr . ... (+4 more) |
14 |
| 32k | βseΓ½di βetraby ββ βlebap βwelayatynyΕ βbir βetrabydyr . βetraplary βwelaΓ½aty ... (+2 more) |
12 |
| 64k | βseΓ½di βetraby ββ βlebap βwelayatynyΕ βbir βetrabydyr . βetraplary βwelaΓ½aty ... (+2 more) |
12 |
Key Findings
- Best Compression: 64k achieves 4.949x compression
- Lowest UNK Rate: 8k with 0.1563% 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 | 11,088 | 13.44 | 23,947 | 14.6% | 32.8% |
| 2-gram | Subword | 355 π | 8.47 | 4,493 | 61.5% | 98.3% |
| 3-gram | Word | 7,047 | 12.78 | 19,707 | 21.5% | 35.2% |
| 3-gram | Subword | 2,934 | 11.52 | 34,530 | 22.8% | 66.5% |
| 4-gram | Word | 20,732 | 14.34 | 46,279 | 14.6% | 21.3% |
| 4-gram | Subword | 14,717 | 13.85 | 159,071 | 11.4% | 36.9% |
| 5-gram | Word | 15,656 | 13.93 | 36,681 | 16.0% | 22.7% |
| 5-gram | Subword | 46,546 | 15.51 | 363,230 | 6.8% | 23.5% |
Top 5 N-grams by Size
2-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | Γ½a da |
2,786 |
| 2 | aradan Γ§ykanlar |
2,220 |
| 3 | tema boΓ½unΓ§a |
2,220 |
| 4 | dΓΌnΓ½Γ€ inenler |
2,217 |
| 5 | sebitler boΓ½unΓ§a |
2,216 |
3-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | wakalar sebitler boΓ½unΓ§a |
2,208 |
| 2 | boΓ½unΓ§a tema boΓ½unΓ§a |
2,201 |
| 3 | sebitler boΓ½unΓ§a tema |
2,201 |
| 4 | dΓΌnΓ½Γ€ inenler aradan |
2,174 |
| 5 | inenler aradan Γ§ykanlar |
2,174 |
4-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | sebitler boΓ½unΓ§a tema boΓ½unΓ§a |
2,201 |
| 2 | wakalar sebitler boΓ½unΓ§a tema |
2,196 |
| 3 | dΓΌnΓ½Γ€ inenler aradan Γ§ykanlar |
2,174 |
| 4 | tema boΓ½unΓ§a noinclude dΓΌnΓ½Γ€ |
2,119 |
| 5 | boΓ½unΓ§a noinclude dΓΌnΓ½Γ€ inenler |
2,119 |
5-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | wakalar sebitler boΓ½unΓ§a tema boΓ½unΓ§a |
2,196 |
| 2 | tema boΓ½unΓ§a noinclude dΓΌnΓ½Γ€ inenler |
2,119 |
| 3 | sebitler boΓ½unΓ§a tema boΓ½unΓ§a noinclude |
2,112 |
| 4 | boΓ½unΓ§a tema boΓ½unΓ§a noinclude dΓΌnΓ½Γ€ |
2,112 |
| 5 | noinclude dΓΌnΓ½Γ€ inenler aradan Γ§ykanlar |
2,085 |
2-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | a r |
188,493 |
| 2 | l a |
152,165 |
| 3 | a n |
151,310 |
| 4 | _ b |
146,537 |
| 5 | a _ |
138,776 |
3-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | l a r |
82,667 |
| 2 | a r y |
58,594 |
| 3 | y Ε _ |
57,971 |
| 4 | a n _ |
55,883 |
| 5 | r . _ |
53,874 |
4-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | l a r y |
41,638 |
| 2 | n y Ε _ |
30,386 |
| 3 | _ w e _ |
29,297 |
| 4 | y n d a |
26,755 |
| 5 | l e r i |
26,718 |
5-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ b i l e |
16,563 |
| 2 | i l e n _ |
16,493 |
| 3 | y n d a _ |
16,259 |
| 4 | y n y Ε _ |
15,844 |
| 5 | b i l e n |
14,698 |
Key Findings
- Best Perplexity: 2-gram (subword) with 355
- Entropy Trend: Decreases with larger n-grams (more predictable)
- Coverage: Top-1000 patterns cover ~23% 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 | 0.8425 | 1.793 | 5.31 | 167,857 | 15.8% |
| 1 | Subword | 1.0332 | 2.047 | 8.72 | 1,227 | 0.0% |
| 2 | Word | 0.1779 | 1.131 | 1.35 | 888,328 | 82.2% |
| 2 | Subword | 1.0291 | 2.041 | 6.32 | 10,675 | 0.0% |
| 3 | Word | 0.0393 | 1.028 | 1.06 | 1,193,586 | 96.1% |
| 3 | Subword | 0.8531 | 1.806 | 4.15 | 67,431 | 14.7% |
| 4 | Word | 0.0110 π | 1.008 | 1.01 | 1,255,469 | 98.9% |
| 4 | Subword | 0.6220 | 1.539 | 2.69 | 279,783 | 37.8% |
Generated Text Samples (Word-based)
Below are text samples generated from each word-based Markov chain model:
Context Size 1:
we hemiΕe eline dΓΌΕΓΌpdir aΓ½allaryΓ± hΓ€kimlik edΓ½Γ€r bangkokdaky Γ½urduΕ 12 15 eretriΓ½adan hem de Γ½ylyΕ ...bilen icc bΓΌtindΓΌnΓ½Γ€ gΓΌni kyΓ½amat gΓΌnΓΌni alada ΓΌns berilΓ½Γ€r asteroidler Γ½aly dΓΌzΓΌp ol birwagtlar zaΓ½...hem satuwa Γ§ykaryldy awstro wengriΓ½a bilen kagyz Γ½ΓΌzΓΌndeligine galdy ΕΎ gulart kΓ€bir bΓΆlekleriniΕ geΓ§...
Context Size 2:
Γ½a da mikaΓ½yl bin seljuk bin dΓΌkak Γ½ylda mΓ€lik Εa ΓΌΓ§in jelaly kalendaryny hijri kalendaryny mysal hΓΆ...tema boΓ½unΓ§a noinclude dΓΌnΓ½Γ€ inenler aradan Γ§ykanlar kategoriΓ½adΓΌnΓ½Γ€ inenler aradan Γ§ykanlar salgylanmalar
Context Size 3:
wakalar sebitler boΓ½unΓ§a tema boΓ½unΓ§a noinclude dΓΌnΓ½Γ€ inenler aradan Γ§ykanlar 31boΓ½unΓ§a tema boΓ½unΓ§a noinclude dΓΌnΓ½Γ€ inenler aradan Γ§ykanlar 104sebitler boΓ½unΓ§a tema boΓ½unΓ§a noinclude dΓΌnΓ½Γ€ inenler aradan Γ§ykanlar 29
Context Size 4:
sebitler boΓ½unΓ§a tema boΓ½unΓ§a noinclude dΓΌnΓ½Γ€ inenler aradan Γ§ykanlar 26wakalar sebitler boΓ½unΓ§a tema boΓ½unΓ§a noinclude dΓΌnΓ½Γ€ inenler aradan Γ§ykanlar baΓ½ramΓ§ylyklarboΓ½unΓ§a noinclude dΓΌnΓ½Γ€ inenler aradan Γ§ykanlar towΕan esenowa hydyr derΓ½aΓ½ew kerim gurbannepesow
Generated Text Samples (Subword-based)
Below are text samples generated from each subword-based Markov chain model:
Context Size 1:
_botaΓ½Γ€rkmp),_ΓΆza_gumgitdar_nyleebury_der._Γ½asah
Context Size 2:
ar._oduΕli_dΓΌΕdirlar.ilbaΕdyry,_oban_emlΓΌndama_(Γ½ar
Context Size 3:
laryΕ_daΕly_ΕΓΌbhesary_12-150-nji_milyΕ_aΓ½atynyΕ_keΕler
Context Size 4:
lary_deΕde_gΓΆlli,_onyΕ_bolandygynda_ru_we_goΕuny,_hassa_t
Key Findings
- Best Predictability: Context-4 (word) with 98.9% predictability
- Branching Factor: Decreases with context size (more deterministic)
- Memory Trade-off: Larger contexts require more storage (279,783 contexts)
- Recommendation: Context-3 or Context-4 for text generation
4. Vocabulary Analysis
Statistics
| Metric | Value |
|---|---|
| Vocabulary Size | 70,850 |
| Total Tokens | 1,266,247 |
| Mean Frequency | 17.87 |
| Median Frequency | 4 |
| Frequency Std Dev | 172.27 |
Most Common Words
| Rank | Word | Frequency |
|---|---|---|
| 1 | we | 29,419 |
| 2 | bilen | 14,593 |
| 3 | hem | 9,723 |
| 4 | bu | 9,296 |
| 5 | bir | 7,148 |
| 6 | ΓΌΓ§in | 7,116 |
| 7 | da | 6,676 |
| 8 | boΓ½unΓ§a | 6,346 |
| 9 | ol | 6,099 |
| 10 | Γ½ylda | 5,569 |
Least Common Words (from vocabulary)
| Rank | Word | Frequency |
|---|---|---|
| 1 | halaΓ§da | 2 |
| 2 | byradarlygynyΕ | 2 |
| 3 | halaja | 2 |
| 4 | bakynyΕ | 2 |
| 5 | esaslandyrylanlar | 2 |
| 6 | ailΙsi | 2 |
| 7 | yΓΆrΓΌkler | 2 |
| 8 | Γ½arymgoragΓ§ysy | 2 |
| 9 | jizak | 2 |
| 10 | kolhozΓ§i | 2 |
Zipf's Law Analysis
| Metric | Value |
|---|---|
| Zipf Coefficient | 0.9487 |
| RΒ² (Goodness of Fit) | 0.992202 |
| Adherence Quality | excellent |
Coverage Analysis
| Top N Words | Coverage |
|---|---|
| Top 100 | 22.4% |
| Top 1,000 | 47.7% |
| Top 5,000 | 70.0% |
| Top 10,000 | 79.1% |
Key Findings
- Zipf Compliance: RΒ²=0.9922 indicates excellent adherence to Zipf's law
- High Frequency Dominance: Top 100 words cover 22.4% of corpus
- Long Tail: 60,850 words needed for remaining 20.9% 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 | 0.8902 | 0.2916 | N/A | N/A |
| mono_64d | 64 | 0.8799 | 0.2188 | N/A | N/A |
| mono_128d | 128 | 0.6945 | 0.1696 | N/A | N/A |
| aligned_32d | 32 | 0.8902 π | 0.2952 | 0.0120 | 0.1680 |
| aligned_64d | 64 | 0.8799 | 0.2224 | 0.0560 | 0.2240 |
| aligned_128d | 128 | 0.6945 | 0.1700 | 0.0840 | 0.3140 |
Key Findings
- Best Isotropy: aligned_32d with 0.8902 (more uniform distribution)
- Semantic Density: Average pairwise similarity of 0.2279. Lower values indicate better semantic separation.
- Alignment Quality: Aligned models achieve up to 8.4% 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 | -0.035 | Low formulaic 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 |
|---|---|
-a |
awyny, andrΓ½u, alta |
-s |
saklanΓ½andyr, saΓ½ylmadyk, stories |
-g |
gyΕy, guzlar, gallipoli |
-b |
beloklaryny, basΓlio, basylan |
-m |
meΓ½i, maersk, mortier |
-k |
kekene, klisfeniΕ, kesil |
-d |
diskriminasiΓ½a, deΕlemek, dakylΓ½ar |
-t |
theodore, territoriΓ½asyndaky, taΓ½ynlapdyr |
Productive Suffixes
| Suffix | Examples |
|---|---|
-Ε |
operasiΓ½alaryΕ, klisfeniΕ, aΕgabadyΕ |
-r |
saklanΓ½andyr, guzlar, mortier |
-y |
beloklaryny, gyΕy, awyny |
-a |
diskriminasiΓ½a, alta, gatyΕmagynda |
-yΕ |
operasiΓ½alaryΕ, aΕgabadyΕ, wahΓ½yΕ |
-n |
humaΓ½un, basylan, araΓ§Γ€kleΕΓ½Γ€n |
-i |
meΓ½i, redmi, eriΕleri |
-an |
basylan, gan, barylΓ½an |
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 |
|---|---|---|---|
kmen |
3.11x | 26 contexts | rkmen, sΓΆkmen, Γ§ekmen |
anla |
1.82x | 155 contexts | sanlar, panlar, hanlar |
asyn |
1.76x | 181 contexts | Γ½asyn, masyn, gasyn |
erin |
1.91x | 103 contexts | lerin, erine, yerin |
rkme |
3.11x | 14 contexts | rkmen, tΓΌrkmer, turkmen |
tlar |
1.70x | 133 contexts | atlar, otlar, otlara |
rler |
1.83x | 86 contexts | Γ€rler, ΓΏrler, Γ½erler |
nlar |
1.84x | 79 contexts | onlar, gunlar, hunlar |
erle |
1.63x | 96 contexts | Γ½erler, α»³erler, gerlen |
ylar |
1.63x | 72 contexts | lylar, kylar, sylar |
rlar |
1.60x | 76 contexts | arlar, durlar, Γ½arlar |
klar |
1.67x | 63 contexts | uklar, klark, oklar |
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 |
|---|---|---|---|
-g |
-y |
123 words | gaΕy, gatnawy |
-g |
-r |
121 words | gaΓ§ypdyrlar, girilΓ½Γ€r |
-g |
-a |
96 words | gidrogeologiΓ½a, graflyklara |
-b |
-r |
92 words | bir, bazaar |
-g |
-n |
89 words | gaΓ½tarylan, gelmeΓ½Γ€n |
-g |
-i |
88 words | geΓ§megi, gΓΌΓ½Γ§li |
-s |
-Ε |
87 words | sahypalaryΕ, sΓΌΓ½ΓΌmleriniΕ |
-s |
-y |
80 words | sostawyny, satmagy |
-g |
-Ε |
76 words | goΓ½umdarlarynyΕ, guramaklygyΕ |
-b |
-y |
75 words | bozulmagy, bidgatΓ§y |
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 |
|---|---|---|---|
| slawΓ½anlarda | slawΓ½anl-ar-da |
7.5 | ar |
| gΓΆrkezipdir | gΓΆrkezip-di-r |
7.5 | di |
| oktΓ½abrdan | oktΓ½abr-da-n |
7.5 | da |
| balyklaryΓ± | balykl-ar-yΓ± |
7.5 | ar |
| sazandalary | sazandal-ar-y |
7.5 | ar |
| bolanlary | bolanl-ar-y |
7.5 | ar |
| garΕydaΕlary | garΕydaΕl-ar-y |
7.5 | ar |
| halykynyΕ | halyky-n-yΕ |
7.5 | n |
| manjurlaryΕ | manjurl-ar-yΕ |
7.5 | ar |
| mukdarlary | mukdarl-ar-y |
7.5 | ar |
| ybadatlarda | ybadatl-ar-da |
7.5 | ar |
| guΕaklyklary | guΕaklykl-ar-y |
7.5 | ar |
| amallaryΕ | amall-ar-yΕ |
7.5 | ar |
| ugurlarda | ugurl-ar-da |
7.5 | ar |
| Γ½akynlarda | Γ½akynl-ar-da |
7.5 | ar |
6.6 Linguistic Interpretation
Automated Insight: The language Turkmen shows high morphological productivity. The subword models are significantly more efficient than word models, suggesting a rich system of affixation or compounding.
7. Summary & Recommendations
Production Recommendations
| Component | Recommended | Rationale |
|---|---|---|
| Tokenizer | 64k BPE | Best compression (4.95x) |
| N-gram | 2-gram | Lowest perplexity (355) |
| Markov | Context-4 | Highest predictability (98.9%) |
| 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) Γ 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.
RΒ² (Coefficient of Determination)
Definition: Measures how well the linear fit explains the frequency-rank relationship. Ranges from 0 to 1.
Intuition: RΒ² near 1.0 means the data closely follows Zipf's law; lower values indicate deviation from expected word frequency patterns.
What to seek: RΒ² > 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
- π Website: wikilangs.org
- π€ Models: huggingface.co/wikilangs
- π Data: wikipedia-monthly
- π€ Author: Omar Kamali
- π€ Sponsor: Featherless AI
Generated by Wikilangs Models Pipeline
Report Date: 2026-01-11 01:05:04



















