Dimli (individual language) - Wikilangs Models
Comprehensive Research Report & Full Ablation Study
This repository contains NLP models trained and evaluated by Wikilangs, specifically on Dimli (individual language) 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 | 3.111x | 3.11 | 0.0973% | 324,747 |
| 16k | 3.420x | 3.42 | 0.1070% | 295,419 |
| 32k | 3.692x | 3.70 | 0.1155% | 273,644 |
| 64k | 3.946x π | 3.95 | 0.1234% | 256,028 |
Tokenization Examples
Below are sample sentences tokenized with each vocabulary size:
Sample 1: .weir, nameyΓͺ bandΔ±ra sewiyaya serΓͺna jeneriko (be Δ°ngΔ±lΔ±zki: Generic top-level ...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | β. we ir , βnameyΓͺ βbandΔ±ra βsewiyaya βserΓͺna βjeneriko β( ... (+19 more) |
29 |
| 16k | β. we ir , βnameyΓͺ βbandΔ±ra βsewiyaya βserΓͺna βjeneriko β( ... (+19 more) |
29 |
| 32k | β. we ir , βnameyΓͺ βbandΔ±ra βsewiyaya βserΓͺna βjeneriko β( ... (+19 more) |
29 |
| 64k | β. we ir , βnameyΓͺ βbandΔ±ra βsewiyaya βserΓͺna βjeneriko β( ... (+19 more) |
29 |
Sample 2: Bègues, dewleta Fransa de, mıntıqaya Auvergne-Rhône-Alpes miyan de yew komuna wı...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βb Γ¨ gues , βdewleta βfransa βde , βmΔ±ntΔ±qaya βauvergne ... (+15 more) |
25 |
| 16k | βb Γ¨ gues , βdewleta βfransa βde , βmΔ±ntΔ±qaya βauvergne ... (+15 more) |
25 |
| 32k | βb Γ¨ gues , βdewleta βfransa βde , βmΔ±ntΔ±qaya βauvergne ... (+15 more) |
25 |
| 64k | βbΓ¨ gues , βdewleta βfransa βde , βmΔ±ntΔ±qaya βauvergne - ... (+14 more) |
24 |
Sample 3: Cosne-d'Allier, dewleta Fransa de, mΔ±ntΔ±qaya Overn-Ron-Alpan miyan de yew komuna...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βcos ne - d ' allier , βdewleta βfransa βde ... (+21 more) |
31 |
| 16k | βcos ne - d ' allier , βdewleta βfransa βde ... (+19 more) |
29 |
| 32k | βcos ne - d ' allier , βdewleta βfransa βde ... (+18 more) |
28 |
| 64k | βcos ne - d ' allier , βdewleta βfransa βde ... (+18 more) |
28 |
Key Findings
- Best Compression: 64k achieves 3.946x compression
- Lowest UNK Rate: 8k with 0.0973% 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 | 2,900 | 11.50 | 32,472 | 37.7% | 66.7% |
| 2-gram | Subword | 361 π | 8.50 | 6,487 | 60.7% | 98.0% |
| 3-gram | Word | 2,363 | 11.21 | 37,780 | 38.7% | 72.4% |
| 3-gram | Subword | 3,111 | 11.60 | 45,197 | 22.3% | 67.0% |
| 4-gram | Word | 3,683 | 11.85 | 77,102 | 34.1% | 68.2% |
| 4-gram | Subword | 15,466 | 13.92 | 232,167 | 13.2% | 42.0% |
| 5-gram | Word | 3,179 | 11.63 | 61,892 | 33.7% | 70.0% |
| 5-gram | Subword | 42,786 | 15.38 | 597,917 | 10.1% | 34.5% |
Top 5 N-grams by Size
2-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | de ca |
13,749 |
| 2 | de mΔ±ntΔ±qaya |
12,351 |
| 3 | ca gΓͺno |
11,945 |
| 4 | fransa de |
11,892 |
| 5 | de yew |
11,359 |
3-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | fransa de mΔ±ntΔ±qaya |
11,768 |
| 2 | dewleta fransa de |
11,147 |
| 3 | de ca gΓͺno |
10,321 |
| 4 | bΔ±vΓͺnΓͺn lista komunanΓͺ |
8,041 |
| 5 | katalogΓͺ neweyΓͺ pΓͺroyi |
7,026 |
4-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | dewleta fransa de mΔ±ntΔ±qaya |
11,101 |
| 2 | katalogΓͺ neweyΓͺ pΓͺroyi de |
7,025 |
| 3 | cΔ±sΔ±m katalogΓͺ neweyΓͺ pΓͺroyi |
7,025 |
| 4 | no cΔ±sΔ±m katalogΓͺ neweyΓͺ |
6,678 |
| 5 | lista cΔ±smanΓͺ ngc gΔ±reyΓͺ |
6,644 |
5-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | cΔ±sΔ±m katalogΓͺ neweyΓͺ pΓͺroyi de |
7,024 |
| 2 | no cΔ±sΔ±m katalogΓͺ neweyΓͺ pΓͺroyi |
6,678 |
| 3 | lista cΔ±smanΓͺ ngc gΔ±reyΓͺ teberi |
6,644 |
| 4 | de ca gΓͺno de terefΓͺ |
5,997 |
| 5 | asmΓͺniyo no cΔ±sΔ±m katalogΓͺ neweyΓͺ |
5,870 |
2-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | a _ |
300,863 |
| 2 | e _ |
289,730 |
| 3 | a n |
274,481 |
| 4 | Γͺ _ |
267,322 |
| 5 | _ d |
217,060 |
3-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ d e |
157,628 |
| 2 | d e _ |
100,392 |
| 3 | o . _ |
73,592 |
| 4 | n Γͺ _ |
68,515 |
| 5 | i y a |
67,461 |
4-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ d e _ |
94,419 |
| 2 | a n Γͺ _ |
43,769 |
| 3 | _ y e w |
40,703 |
| 4 | _ k o m |
40,690 |
| 5 | _ r a _ |
38,802 |
5-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ y e w _ |
36,954 |
| 2 | _ k o m u |
34,451 |
| 3 | k o m u n |
34,446 |
| 4 | _ b Δ± v Γͺ |
23,569 |
| 5 | b Δ± v Γͺ n |
23,557 |
Key Findings
- Best Perplexity: 2-gram (subword) with 361
- Entropy Trend: Decreases with larger n-grams (more predictable)
- Coverage: Top-1000 patterns cover ~35% 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 | 0.7487 | 1.680 | 4.43 | 220,418 | 25.1% |
| 1 | Subword | 0.9728 | 1.963 | 6.81 | 2,853 | 2.7% |
| 2 | Word | 0.1773 | 1.131 | 1.38 | 970,777 | 82.3% |
| 2 | Subword | 0.8745 | 1.833 | 5.24 | 19,403 | 12.6% |
| 3 | Word | 0.0542 | 1.038 | 1.10 | 1,326,261 | 94.6% |
| 3 | Subword | 0.7728 | 1.709 | 4.01 | 101,524 | 22.7% |
| 4 | Word | 0.0216 π | 1.015 | 1.04 | 1,442,368 | 97.8% |
| 4 | Subword | 0.6913 | 1.615 | 2.98 | 406,622 | 30.9% |
Generated Text Samples (Word-based)
Below are text samples generated from each word-based Markov chain model:
Context Size 1:
de biyΓͺ ke yew belediyaya sΓ»kΓͺ wayiye nΔ±fus grafikΓͺ diagrami sero gorey serran ra nΔ±fusΓͺ vilasantarra nΔ±fusΓͺ anouldi website resayΔ±Ε 14 807 windsor ontario kanada yew qezay lalapaΕaya ekonomiye be ro...yew komunΓͺ aulnois beaufremont de anciyao embΔ±ryani nΔ±fus bΔ±vΓͺnΓͺn qam hewahebur kelek u nameyΓͺ bandΔ±...
Context Size 2:
de ca gΓͺno schleswig holsteini de wΔ±layetΓͺ ardennesi de yew serra teqwimiya seramey biyayΔ±Ε gaius pl...de mΔ±ntΔ±qaya normandiya de ca gΓͺno xΔ±zmete gesnes en argonne ca gΓͺnΓͺ xΔ±zmete rozerotte de Εebekey aw...ca gΓͺno bΔ±vΓͺnΓͺn lista komunanΓͺ loire atlantique pays de la loire de ca gΓͺna xΔ±zmete escouloubre de
Context Size 3:
fransa de mΔ±ntΔ±qaya occitanie de ca gΓͺna xΔ±zmete trausse de Εebekey awe esto Γ» sistemΓͺ kanalizasyoni...dewleta fransa de mΔ±ntΔ±qaya auvergne rhΓ΄ne alpesi miyan de yew komuna bΔ±vΓͺnΓͺn lista komunanΓͺ seine e...de ca gΓͺno embΔ±ryani nΔ±fus grafikΓͺ diagrami sero gorey seran ra nΔ±fusΓͺ sandiΓ‘s bΔ±vΓͺnΓͺn belediyey our...
Context Size 4:
dewleta fransa de mΔ±ntΔ±qaya grand esti de wΔ±layetΓͺ vosgesi dero komuni 31 87 km2 ca gΓͺno dormey herb...katalogΓͺ neweyΓͺ pΓͺroyi de komΓͺ estareyanΓͺ miyan de ca gΓͺno de terefΓͺ i ra keΕΔ±f biyo bΔ±vΓͺnΓͺn asmΓͺn g...cΔ±sΔ±m katalogΓͺ neweyΓͺ pΓͺroyi de komΓͺ estareyanΓͺ miyan de ca gΓͺno de terefΓͺ astronom i ra keΕΔ±f biyo ...
Generated Text Samples (Subword-based)
Below are text samples generated from each subword-based Markov chain model:
Context Size 1:
_6_gaus-seyan_zΔ±eyirdΓͺ_ardullaleanΓͺn_d_usi_n-cet
Context Size 2:
a_fra_hun_no_Γ»_hoe_letektempar_β_danΓͺ_man_lolynsall
Context Size 3:
_de_temΓͺ_ki_sec,_yde_verneyo_ra_nowso._telebebat_yΔ±lbΔ±
Context Size 4:
_de_komunΓͺ_wΔ±layetΓͺanΓͺ_muzisyeno,_ber__yew_film_rol_Γ§akal
Key Findings
- Best Predictability: Context-4 (word) with 97.8% predictability
- Branching Factor: Decreases with context size (more deterministic)
- Memory Trade-off: Larger contexts require more storage (406,622 contexts)
- Recommendation: Context-3 or Context-4 for text generation
4. Vocabulary Analysis
Statistics
| Metric | Value |
|---|---|
| Vocabulary Size | 92,779 |
| Total Tokens | 2,332,304 |
| Mean Frequency | 25.14 |
| Median Frequency | 3 |
| Frequency Std Dev | 515.39 |
Most Common Words
| Rank | Word | Frequency |
|---|---|---|
| 1 | de | 115,037 |
| 2 | ra | 40,569 |
| 3 | yew | 37,084 |
| 4 | u | 26,509 |
| 5 | bΔ±vΓͺnΓͺn | 23,466 |
| 6 | Γ» | 21,932 |
| 7 | lista | 20,682 |
| 8 | ca | 17,900 |
| 9 | dewleta | 17,340 |
| 10 | ke | 16,742 |
Least Common Words (from vocabulary)
| Rank | Word | Frequency |
|---|---|---|
| 1 | aksiyongerilim | 2 |
| 2 | vizyonkewtΔ±Ε | 2 |
| 3 | sude | 2 |
| 4 | alΔ±nca | 2 |
| 5 | vurmaz | 2 |
| 6 | dramgerilim | 2 |
| 7 | gΓΌlsoy | 2 |
| 8 | sarsu | 2 |
| 9 | toktamΔ±ΕoΔlu | 2 |
| 10 | ΓΆΔden | 2 |
Zipf's Law Analysis
| Metric | Value |
|---|---|
| Zipf Coefficient | 1.0696 |
| RΒ² (Goodness of Fit) | 0.997357 |
| Adherence Quality | excellent |
Coverage Analysis
| Top N Words | Coverage |
|---|---|
| Top 100 | 39.8% |
| Top 1,000 | 65.1% |
| Top 5,000 | 78.5% |
| Top 10,000 | 84.0% |
Key Findings
- Zipf Compliance: RΒ²=0.9974 indicates excellent adherence to Zipf's law
- High Frequency Dominance: Top 100 words cover 39.8% of corpus
- Long Tail: 82,779 words needed for remaining 16.0% 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 | 0.8232 | 0.3686 | N/A | N/A |
| mono_64d | 64 | 0.7882 | 0.3130 | N/A | N/A |
| mono_128d | 128 | 0.5576 | 0.2631 | N/A | N/A |
| aligned_32d | 32 | 0.8232 π | 0.3734 | 0.0360 | 0.2220 |
| aligned_64d | 64 | 0.7882 | 0.3026 | 0.0680 | 0.3100 |
| aligned_128d | 128 | 0.5576 | 0.2680 | 0.1060 | 0.4260 |
Key Findings
- Best Isotropy: aligned_32d with 0.8232 (more uniform distribution)
- Semantic Density: Average pairwise similarity of 0.3148. Lower values indicate better semantic separation.
- Alignment Quality: Aligned models achieve up to 10.6% 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 | 1.030 | 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 |
|---|
Productive Suffixes
| Suffix | Examples |
|---|---|
-an |
ban, yewbiyayiyan, algan |
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 |
|---|---|---|---|
iyay |
1.76x | 207 contexts | niyay, siyay, Εiyay |
iyan |
1.73x | 143 contexts | biyan, niyan, ziyan |
ista |
1.71x | 64 contexts | kista, lista, vista |
eber |
1.92x | 37 contexts | teber, zeber, xeber |
wlet |
2.29x | 20 contexts | dewlet, dewletu, dewleto |
ewle |
2.23x | 20 contexts | dewle, sewle, hewle |
leta |
1.95x | 30 contexts | letan, aleta, Δeleta |
nter |
1.78x | 41 contexts | enter, inter, anter |
rans |
1.84x | 35 contexts | crans, frans, trans |
laye |
2.00x | 23 contexts | claye, layer, alaye |
Δ±ntΔ± |
2.38x | 12 contexts | alΔ±ntΔ±, saΓ§Δ±ntΔ±, Γ§alΔ±ntΔ± |
ntΔ±q |
1.93x | 18 contexts | mantΔ±q, mentΔ±q, mentΔ±qi |
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 |
|---|---|---|---|
| vΔ±nderdΔ±Εan | vΔ±nderdΔ±Ε-an |
4.5 | vΔ±nderdΔ±Ε |
| hΔ±kumetan | hΔ±kumet-an |
4.5 | hΔ±kumet |
| pΓͺxamberan | pΓͺxamber-an |
4.5 | pΓͺxamber |
| destnuΕteyan | destnuΕtey-an |
4.5 | destnuΕtey |
| sekuleran | sekuler-an |
4.5 | sekuler |
| beynelmΔ±lelan | beynelmΔ±lel-an |
4.5 | beynelmΔ±lel |
| karxaneyan | karxaney-an |
4.5 | karxaney |
| meqaleyan | meqaley-an |
4.5 | meqaley |
| qerebegan | qerebeg-an |
1.5 | qerebeg |
| boΔazlΔ±yan | boΔazlΔ±y-an |
1.5 | boΔazlΔ±y |
| Γ§Δ±ldirtan | Γ§Δ±ldirt-an |
1.5 | Γ§Δ±ldirt |
| meheliyan | meheliy-an |
1.5 | meheliy |
| saskatchewan | saskatchew-an |
1.5 | saskatchew |
| kalimantan | kalimant-an |
1.5 | kalimant |
| gentleman | gentlem-an |
1.5 | gentlem |
6.6 Linguistic Interpretation
Automated Insight: The language Dimli (individual language) 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 (3.95x) |
| N-gram | 2-gram | Lowest perplexity (361) |
| Markov | Context-4 | Highest predictability (97.8%) |
| 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: 2026-01-04 02:29:30



















