Crimean Tatar - Wikilangs Models
Comprehensive Research Report & Full Ablation Study
This repository contains NLP models trained and evaluated by Wikilangs, specifically on Crimean Tatar 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 | 3.646x | 3.65 | 0.2038% | 212,471 |
| 16k | 4.078x | 4.08 | 0.2279% | 189,960 |
| 32k | 4.457x | 4.46 | 0.2492% | 173,772 |
| 64k | 4.779x π | 4.79 | 0.2672% | 162,079 |
Tokenization Examples
Below are sample sentences tokenized with each vocabulary size:
Sample 1: Δ°slanovo () - Rusiyede, BaΕqΔ±rtistan CumhuriyetiniΓ± KuΕnarenko rayonΔ±nda bir kΓΆy...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βΔ°s lan ovo β() β- βrusiyede , βbaΕqΔ±rtistan βcumhuriyetiniΓ± βkuΕnarenko ... (+13 more) |
23 |
| 16k | βΔ°s lanovo β() β- βrusiyede , βbaΕqΔ±rtistan βcumhuriyetiniΓ± βkuΕnarenko βrayonΔ±nda ... (+12 more) |
22 |
| 32k | βΔ°s lanovo β() β- βrusiyede , βbaΕqΔ±rtistan βcumhuriyetiniΓ± βkuΕnarenko βrayonΔ±nda ... (+12 more) |
22 |
| 64k | βΔ°slanovo β() β- βrusiyede , βbaΕqΔ±rtistan βcumhuriyetiniΓ± βkuΕnarenko βrayonΔ±nda βbir ... (+11 more) |
21 |
Sample 2: Drujbivka () - UkrainanΔ±Γ± JΔ±tomΔ±r vilΓ’yetinde Korosten rayonΔ±nda bir kΓΆy. Ealisi...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βdruj bivka β() β- βukrainanΔ±Γ± βjΔ±tomΔ±r βvilΓ’yetinde βkorosten βrayonΔ±nda βbir ... (+12 more) |
22 |
| 16k | βdruj bivka β() β- βukrainanΔ±Γ± βjΔ±tomΔ±r βvilΓ’yetinde βkorosten βrayonΔ±nda βbir ... (+12 more) |
22 |
| 32k | βdruj bivka β() β- βukrainanΔ±Γ± βjΔ±tomΔ±r βvilΓ’yetinde βkorosten βrayonΔ±nda βbir ... (+12 more) |
22 |
| 64k | βdrujbivka β() β- βukrainanΔ±Γ± βjΔ±tomΔ±r βvilΓ’yetinde βkorosten βrayonΔ±nda βbir βkΓΆy ... (+11 more) |
21 |
Sample 3: Koltunovka () - RusiyeniΓ± Belgorod vilΓ’yetinde, Alekseyevka rayonΔ±nda bir kΓΆy. E...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βkol tun ovka β() β- βrusiyeniΓ± βbelgorod βvilΓ’yetinde , βalekseyevka ... (+15 more) |
25 |
| 16k | βkol tun ovka β() β- βrusiyeniΓ± βbelgorod βvilΓ’yetinde , βalekseyevka ... (+15 more) |
25 |
| 32k | βkol tun ovka β() β- βrusiyeniΓ± βbelgorod βvilΓ’yetinde , βalekseyevka ... (+15 more) |
25 |
| 64k | βkoltunovka β() β- βrusiyeniΓ± βbelgorod βvilΓ’yetinde , βalekseyevka βrayonΔ±nda βbir ... (+13 more) |
23 |
Key Findings
- Best Compression: 64k achieves 4.779x compression
- Lowest UNK Rate: 8k with 0.2038% 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 | 849 | 9.73 | 10,213 | 56.1% | 74.4% |
| 2-gram | Subword | 348 π | 8.44 | 3,878 | 63.4% | 98.0% |
| 3-gram | Word | 1,276 | 10.32 | 13,301 | 49.1% | 71.8% |
| 3-gram | Subword | 2,220 | 11.12 | 29,221 | 33.1% | 71.8% |
| 4-gram | Word | 4,190 | 12.03 | 31,513 | 31.9% | 54.7% |
| 4-gram | Subword | 7,833 | 12.94 | 131,199 | 26.0% | 52.3% |
| 5-gram | Word | 6,061 | 12.57 | 29,487 | 24.1% | 48.5% |
| 5-gram | Subword | 16,690 | 14.03 | 285,107 | 23.4% | 46.1% |
Top 5 N-grams by Size
2-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | ealisiniΓ± sayΔ±sΔ± |
20,740 |
| 2 | rayonΔ±nda bir |
17,352 |
| 3 | meskΓΌn yerler |
12,883 |
| 4 | bir kΓΆy |
10,061 |
| 5 | kΓΆy ealisiniΓ± |
9,139 |
3-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | rayonΔ±nda bir kΓΆy |
9,314 |
| 2 | bir kΓΆy ealisiniΓ± |
9,139 |
| 3 | kΓΆy ealisiniΓ± sayΔ±sΔ± |
9,139 |
| 4 | rayonΔ±ndaki meskΓΌn yerler |
5,591 |
| 5 | kiΕi meskΓΌn yerler |
4,604 |
4-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | bir kΓΆy ealisiniΓ± sayΔ±sΔ± |
9,139 |
| 2 | rayonΔ±nda bir kΓΆy ealisiniΓ± |
8,985 |
| 3 | bir kΓΆydir ealisiniΓ± sayΔ±sΔ± |
4,601 |
| 4 | rayonΔ±nda bir kΓΆydir ealisiniΓ± |
4,565 |
| 5 | iΜhtar rayonΔ±ndaki meskΓΌn yerler |
3,615 |
5-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | rayonΔ±nda bir kΓΆy ealisiniΓ± sayΔ±sΔ± |
8,985 |
| 2 | rayonΔ±nda bir kΓΆydir ealisiniΓ± sayΔ±sΔ± |
4,565 |
| 3 | kiΕi iΜhtar rayonΔ±ndaki meskΓΌn yerler |
2,558 |
| 4 | asΔ±rnΔ±Γ± bir senesi vaqialar doΔumlar |
1,996 |
| 5 | bir senesi vaqialar doΔumlar ΓΆlΓΌmler |
1,917 |
2-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | i n |
101,089 |
| 2 | e r |
95,398 |
| 3 | a _ |
88,613 |
| 4 | r _ |
84,598 |
| 5 | . _ |
80,856 |
3-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | i Γ± _ |
43,406 |
| 2 | n i Γ± |
42,914 |
| 3 | l e r |
42,891 |
| 4 | n d e |
35,848 |
| 5 | e t i |
35,643 |
4-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | n i Γ± _ |
42,657 |
| 2 | i n d e |
34,217 |
| 3 | y e t i |
30,830 |
| 4 | Δ± n d a |
30,087 |
| 5 | _ b i r |
29,643 |
5-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | i n i Γ± _ |
28,194 |
| 2 | y e t i n |
28,057 |
| 3 | _ b i r _ |
27,628 |
| 4 | r a y o n |
26,921 |
| 5 | _ r a y o |
26,900 |
Key Findings
- Best Perplexity: 2-gram (subword) with 348
- Entropy Trend: Decreases with larger n-grams (more predictable)
- Coverage: Top-1000 patterns cover ~46% 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 | 0.6244 | 1.542 | 2.99 | 128,666 | 37.6% |
| 1 | Subword | 0.8852 | 1.847 | 6.85 | 1,505 | 11.5% |
| 2 | Word | 0.1302 | 1.094 | 1.24 | 383,467 | 87.0% |
| 2 | Subword | 0.9025 | 1.869 | 5.57 | 10,300 | 9.7% |
| 3 | Word | 0.0387 | 1.027 | 1.07 | 474,016 | 96.1% |
| 3 | Subword | 0.8153 | 1.760 | 3.87 | 57,358 | 18.5% |
| 4 | Word | 0.0242 π | 1.017 | 1.05 | 502,796 | 97.6% |
| 4 | Subword | 0.6069 | 1.523 | 2.54 | 221,948 | 39.3% |
Generated Text Samples (Word-based)
Below are text samples generated from each word-based Markov chain model:
Context Size 1:
bir cemaatΔ± ukrainanΔ±Γ± jΔ±tomΔ±r vilΓ’yetinde olevsk rayonΔ±nda bir Εeer Εeklinde qasabalar vahruΕev nog...kiΕi rayonΔ±ndaki meskΓΌn yerler kΓΆyler abatskoye rusiyeniΓ± hantΔ± mansi muhtar cumhuriyetinΔ±Γ± devlet g...sayΔ±sΔ± 0 kiΕi meskΓΌn yerler veloturizm iklim deΓ±iΕmelerine Γ§oq yΓΌklΓΌ yΓΌkni yΓΌkniΓ± yΓΌksek mΓΆlekulΓ’r o...
Context Size 2:
ealisiniΓ± sayΔ±sΔ± kiΕi senesi vilΓ’yetindeki qasabalarrayonΔ±nda bir aul adΔ±ge habl calancΓΌk kiΓ§ik iΜncik kavkazskiy pregradna ΓΌΓ§kΓΆken habez erkin Εeer rus...bir kΓΆy oktΓ’br rayonΔ±nΔ±Γ± merkezi ealisiniΓ± sayΔ±sΔ± 202 939 kiΕi senesi atΔ±flar rayonΔ±ndaki meskΓΌn yer...
Context Size 3:
rayonΔ±nda bir kΓΆy ealisiniΓ± sayΔ±sΔ± 394 kiΕi senesi atΔ±flar rayonΔ±ndaki meskΓΌn yerler kΓΆyler atΔ±flar ...bir kΓΆy ealisiniΓ± sayΔ±sΔ± 593 kiΕi iΜhtar rayonΔ±ndaki meskΓΌn yerler kΓΆyler atΔ±flar rayonΔ±ndaki meskΓΌn...kΓΆy ealisiniΓ± sayΔ±sΔ± 828 kiΕi vilΓ’yetindeki meskΓΌn yerler
Context Size 4:
bir kΓΆy ealisiniΓ± sayΔ±sΔ± kiΕi vilΓ’yetindeki meskΓΌn yerlerrayonΔ±nda bir kΓΆy ealisiniΓ± sayΔ±sΔ± 134 kiΕi vilΓ’yetindeki meskΓΌn yerlerbir kΓΆydir ealisiniΓ± sayΔ±sΔ± 25 kiΕi iΜhtar rayonΔ±ndaki meskΓΌn yerler vilΓ’yetindeki Εeer Εeklinde qas...
Generated Text Samples (Subword-based)
Below are text samples generated from each subword-based Markov chain model:
Context Size 1:
_()_-_qmΔ±_mi._beariraye_altviyΓΌri._biΕekayay._()
Context Size 2:
iniv-ufterlar,_ada_balisiyentΔ±larir_rusiyetingrayΔ±s
Context Size 3:
iΓ±_sayΔ±sΔ±_591_belgniΓ±_sayΔ±sΔ±_kir._eande_dinde_ΓΆgrendi_
Context Size 4:
niΓ±_noviΓ§i_bar._cevinde_kontsev_artemiyetinde_bir_qast_ma
Key Findings
- Best Predictability: Context-4 (word) with 97.6% predictability
- Branching Factor: Decreases with context size (more deterministic)
- Memory Trade-off: Larger contexts require more storage (221,948 contexts)
- Recommendation: Context-3 or Context-4 for text generation
4. Vocabulary Analysis
Statistics
| Metric | Value |
|---|---|
| Vocabulary Size | 51,458 |
| Total Tokens | 776,471 |
| Mean Frequency | 15.09 |
| Median Frequency | 3 |
| Frequency Std Dev | 272.01 |
Most Common Words
| Rank | Word | Frequency |
|---|---|---|
| 1 | bir | 27,753 |
| 2 | kiΕi | 20,857 |
| 3 | sayΔ±sΔ± | 20,821 |
| 4 | ealisiniΓ± | 20,770 |
| 5 | rayonΔ±nda | 17,392 |
| 6 | meskΓΌn | 13,506 |
| 7 | yerler | 12,926 |
| 8 | vilΓ’yetinde | 12,440 |
| 9 | kΓΆy | 10,901 |
| 10 | rusiyeniΓ± | 9,597 |
Least Common Words (from vocabulary)
| Rank | Word | Frequency |
|---|---|---|
| 1 | Π·ΠΈΡΠ΄Π΅ | 2 |
| 2 | atalarnΔ±Γ± | 2 |
| 3 | kotsubΔ±nskΔ±ylar | 2 |
| 4 | yΓΌneskonΔ±Γ± | 2 |
| 5 | Ψ―ΫΩΩΨ± | 2 |
| 6 | Ψ§Ψ²Ψ¨Ψ±Ϋ | 2 |
| 7 | Ψ§ΩΩΨ§Ω | 2 |
| 8 | Ψ³Ψ§Ω Ψ§ΩΪΫ | 2 |
| 9 | ΩΫΨ²Ϋ | 2 |
| 10 | samanΓ§Δ± | 2 |
Zipf's Law Analysis
| Metric | Value |
|---|---|
| Zipf Coefficient | 0.9856 |
| RΒ² (Goodness of Fit) | 0.998043 |
| Adherence Quality | excellent |
Coverage Analysis
| Top N Words | Coverage |
|---|---|
| Top 100 | 45.6% |
| Top 1,000 | 63.8% |
| Top 5,000 | 78.2% |
| Top 10,000 | 84.4% |
Key Findings
- Zipf Compliance: RΒ²=0.9980 indicates excellent adherence to Zipf's law
- High Frequency Dominance: Top 100 words cover 45.6% of corpus
- Long Tail: 41,458 words needed for remaining 15.6% 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 | 0.7031 π | 0.3722 | N/A | N/A |
| mono_64d | 64 | 0.4233 | 0.3424 | N/A | N/A |
| mono_128d | 128 | 0.1068 | 0.3377 | N/A | N/A |
| aligned_32d | 32 | 0.7031 | 0.3786 | 0.0140 | 0.1600 |
| aligned_64d | 64 | 0.4233 | 0.3386 | 0.0380 | 0.2140 |
| aligned_128d | 128 | 0.1068 | 0.3419 | 0.0560 | 0.2680 |
Key Findings
- Best Isotropy: mono_32d with 0.7031 (more uniform distribution)
- Semantic Density: Average pairwise similarity of 0.3519. Lower values indicate better semantic separation.
- Alignment Quality: Aligned models achieve up to 5.6% 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 | 0.052 | 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 |
|---|
Productive Suffixes
| Suffix | Examples |
|---|---|
-a |
terehova, biΓ§ura, observatoriya |
-ka |
novosΓΆlka, alekseyevka, kapustΓ’nka |
-vo |
korolΓΆvo, semenovo, hetovo |
-vka |
alekseyevka, dolgalovka, svetlovka |
-an |
turan, birobican, adlandΔ±rΔan |
-ovo |
semenovo, hetovo, panfilovo |
-ye |
zapolnoye, smelΔ±ye, voznesenskoye |
-en |
keΓ§irmegen, nevbetten, neogen |
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 |
|---|---|---|---|
leri |
1.60x | 110 contexts | ileri, lerik, galeri |
rler |
1.60x | 57 contexts | erler, yerler, derler |
siye |
2.05x | 21 contexts | asiye, rusiye, tevsiye |
isin |
1.57x | 31 contexts | episine, kerisin, reisini |
iniΓ± |
1.64x | 26 contexts | eviniΓ±, iliniΓ±, eliniΓ± |
nesi |
1.64x | 22 contexts | nesib, nesil, nesir |
eniΓ± |
1.75x | 16 contexts | seniΓ±, heniΓ±, ekeniΓ± |
usiy |
2.11x | 9 contexts | lusiya, rusiye, hususiy |
lΓ’ye |
1.87x | 11 contexts | belΓ’yev, gulΓ’yev, vilΓ’yet |
Γ’yet |
1.87x | 11 contexts | menΓ’yet, vilΓ’yet, ΕikΓ’yet |
sini |
1.70x | 14 contexts | siniy, sinip, aksini |
yeti |
1.59x | 17 contexts | yetip, yetim, yetiΕe |
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.
No significant affix co-occurrences detected.
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 |
|---|---|---|---|
| gazetanen | gazet-an-en |
6.0 | gazet |
| ananyevka | anan-ye-vka |
6.0 | anan |
| petrusnΔ±Γ± | petrus-nΔ±Γ± |
4.5 | petrus |
| vesiqalarΔ±nΔ±Γ± | vesiqalarΔ±-nΔ±Γ± |
4.5 | vesiqalarΔ± |
| nikiforovo | nikifor-ovo |
4.5 | nikifor |
| sistemasΔ±nΔ±Γ± | sistemasΔ±-nΔ±Γ± |
4.5 | sistemasΔ± |
| qΔ±sΔ±mlarΔ±nΔ±Γ± | qΔ±sΔ±mlarΔ±-nΔ±Γ± |
4.5 | qΔ±sΔ±mlarΔ± |
| borispolye | borispol-ye |
4.5 | borispol |
| programmanΔ±Γ± | programma-nΔ±Γ± |
4.5 | programma |
| gotlarnΔ±Γ± | gotlar-nΔ±Γ± |
4.5 | gotlar |
| qadΔ±lΔ±qnΔ±Γ± | qadΔ±lΔ±q-nΔ±Γ± |
4.5 | qadΔ±lΔ±q |
| kopelΓ’nka | kopelΓ’n-ka |
4.5 | kopelΓ’n |
| mahsulatlarnΔ±Γ± | mahsulatlar-nΔ±Γ± |
4.5 | mahsulatlar |
| nigeriyanΔ±Γ± | nigeriya-nΔ±Γ± |
4.5 | nigeriya |
| qasabanΔ±Γ± | qasaba-nΔ±Γ± |
4.5 | qasaba |
6.6 Linguistic Interpretation
Automated Insight: The language Crimean Tatar 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 (4.78x) |
| N-gram | 2-gram | Lowest perplexity (348) |
| Markov | Context-4 | Highest predictability (97.6%) |
| 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: 2026-01-03 20:48:59



















