Hungarian - Wikilangs Models
Comprehensive Research Report & Full Ablation Study
This repository contains NLP models trained and evaluated by Wikilangs, specifically on Hungarian 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 | 3.504x | 3.50 | 0.1728% | 3,324,472 |
| 16k | 3.921x | 3.92 | 0.1933% | 2,971,202 |
| 32k | 4.310x | 4.31 | 0.2125% | 2,702,863 |
| 64k | 4.660x π | 4.66 | 0.2298% | 2,499,703 |
Tokenization Examples
Below are sample sentences tokenized with each vocabulary size:
Sample 1: orvlΓΆvΓ©sz, szemΓ©ly β lΓ‘sd: mesterlΓΆvΓ©sz OrvlΓΆvΓ©sz amerikai akciΓ³film
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βorv l ΓΆv Γ©sz , βszemΓ©ly β β βlΓ‘sd : ... (+12 more) |
22 |
| 16k | βorv lΓΆv Γ©sz , βszemΓ©ly ββ βlΓ‘sd : βmester lΓΆv ... (+7 more) |
17 |
| 32k | βorv lΓΆv Γ©sz , βszemΓ©ly ββ βlΓ‘sd : βmester lΓΆv ... (+7 more) |
17 |
| 64k | βorv lΓΆvΓ©sz , βszemΓ©ly ββ βlΓ‘sd : βmesterlΓΆvΓ©sz βorv lΓΆvΓ©sz ... (+2 more) |
12 |
Sample 2: Monterde, telepΓΌlΓ©s SpanyolorszΓ‘gban, Zaragoza tartomΓ‘nyban Monterde de Albarrac...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βmont er de , βtelepΓΌlΓ©s βspanyol orszΓ‘gban , βzar ag ... (+19 more) |
29 |
| 16k | βmont er de , βtelepΓΌlΓ©s βspanyol orszΓ‘gban , βzar ag ... (+19 more) |
29 |
| 32k | βmont er de , βtelepΓΌlΓ©s βspanyol orszΓ‘gban , βzarag oza ... (+17 more) |
27 |
| 64k | βmonter de , βtelepΓΌlΓ©s βspanyol orszΓ‘gban , βzaragoza βtartomΓ‘nyban βmonter ... (+14 more) |
24 |
Sample 3: A Nyoman szΓ³ra a kΓΆvetkezΕ lapok hivatkozhatnak: Nyoman, a Nyeman folyΓ³ belarusz...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βa βnyom an βszΓ³ ra βa βkΓΆvetkezΕ βlap ok βhivatkoz ... (+25 more) |
35 |
| 16k | βa βnyom an βszΓ³ ra βa βkΓΆvetkezΕ βlapok βhivatkoz hatnak ... (+23 more) |
33 |
| 32k | βa βnyom an βszΓ³ ra βa βkΓΆvetkezΕ βlapok βhivatkoz hatnak ... (+21 more) |
31 |
| 64k | βa βnyom an βszΓ³ra βa βkΓΆvetkezΕ βlapok βhivatkoz hatnak : ... (+17 more) |
27 |
Key Findings
- Best Compression: 64k achieves 4.660x compression
- Lowest UNK Rate: 8k with 0.1728% 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 | 534,583 | 19.03 | 4,267,292 | 5.3% | 13.6% |
| 2-gram | Subword | 435 π | 8.77 | 36,188 | 54.2% | 98.1% |
| 3-gram | Word | 2,075,420 | 20.98 | 7,553,147 | 2.6% | 6.6% |
| 3-gram | Subword | 4,599 | 12.17 | 265,628 | 17.2% | 55.9% |
| 4-gram | Word | 4,222,921 | 22.01 | 12,285,779 | 2.7% | 6.1% |
| 4-gram | Subword | 30,520 | 14.90 | 1,702,927 | 7.5% | 26.9% |
| 5-gram | Word | 3,104,259 | 21.57 | 8,851,426 | 3.4% | 7.3% |
| 5-gram | Subword | 140,455 | 17.10 | 6,669,073 | 3.8% | 16.0% |
Top 5 N-grams by Size
2-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | Γ©s a |
750,740 |
| 2 | hogy a |
246,908 |
| 3 | tovΓ‘bbi informΓ‘ciΓ³k |
239,762 |
| 4 | Γ©s az |
222,085 |
| 5 | volt a |
210,831 |
3-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | jegyzetek tovΓ‘bbi informΓ‘ciΓ³k |
116,226 |
| 2 | nΓ©pessΓ©g a telepΓΌlΓ©s |
75,437 |
| 3 | szemΓ©lyek elhunyt szemΓ©lyek |
70,441 |
| 4 | szΓΌletett szemΓ©lyek elhunyt |
69,726 |
| 5 | tovΓ‘bbi informΓ‘ciΓ³k megye |
43,373 |
4-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | szΓΌletett szemΓ©lyek elhunyt szemΓ©lyek |
69,726 |
| 2 | a telepΓΌlΓ©s nΓ©pessΓ©gΓ©nek vΓ‘ltozΓ‘sa |
42,715 |
| 3 | nΓ©pessΓ©g a telepΓΌlΓ©s nΓ©pessΓ©gΓ©nek |
42,581 |
| 4 | jegyzetek tovΓ‘bbi informΓ‘ciΓ³k megye |
41,857 |
| 5 | megyΓ©ben nΓ©pessΓ©g a telepΓΌlΓ©s |
40,991 |
5-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | nΓ©pessΓ©g a telepΓΌlΓ©s nΓ©pessΓ©gΓ©nek vΓ‘ltozΓ‘sa |
42,500 |
| 2 | jegyzetek tovΓ‘bbi informΓ‘ciΓ³k megye telepΓΌlΓ©sei |
39,789 |
| 3 | tovΓ‘bbi informΓ‘ciΓ³k megye telepΓΌlΓ©sei lΓ©trehozott |
38,604 |
| 4 | telepΓΌlΓ©sei lΓ©trehozott francia telepΓΌlΓ©s cikkek |
33,554 |
| 5 | megye telepΓΌlΓ©sei lΓ©trehozott francia telepΓΌlΓ©s |
33,497 |
2-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ a |
28,615,318 |
| 2 | a _ |
26,126,954 |
| 3 | s z |
20,526,948 |
| 4 | t _ |
17,995,334 |
| 5 | e l |
17,138,516 |
3-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ a _ |
14,744,854 |
| 2 | _ s z |
7,371,389 |
| 3 | _ a z |
5,409,490 |
| 4 | Γ© s _ |
5,376,301 |
| 5 | s z e |
5,046,767 |
4-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ a z _ |
4,706,514 |
| 2 | _ Γ© s _ |
4,404,673 |
| 3 | _ e g y |
2,864,622 |
| 4 | _ m e g |
2,653,603 |
| 5 | _ s z e |
2,581,753 |
5-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ s z e r |
1,290,178 |
| 2 | _ a z _ e |
1,248,859 |
| 3 | _ Γ© s _ a |
1,122,375 |
| 4 | _ e g y _ |
1,119,120 |
| 5 | _ v o l t |
1,080,101 |
Key Findings
- Best Perplexity: 2-gram (subword) with 435
- Entropy Trend: Decreases with larger n-grams (more predictable)
- Coverage: Top-1000 patterns cover ~16% 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 | 0.9149 | 1.885 | 11.86 | 5,253,585 | 8.5% |
| 1 | Subword | 1.3264 | 2.508 | 10.40 | 16,190 | 0.0% |
| 2 | Word | 0.3314 | 1.258 | 2.16 | 62,241,118 | 66.9% |
| 2 | Subword | 0.6166 | 1.533 | 4.07 | 168,239 | 38.3% |
| 3 | Word | 0.1296 | 1.094 | 1.28 | 134,211,461 | 87.0% |
| 3 | Subword | 0.6817 | 1.604 | 4.31 | 684,267 | 31.8% |
| 4 | Word | 0.0479 π | 1.034 | 1.08 | 171,557,270 | 95.2% |
| 4 | Subword | 0.7163 | 1.643 | 3.92 | 2,950,554 | 28.4% |
Generated Text Samples (Word-based)
Below are text samples generated from each word-based Markov chain model:
Context Size 1:
a legkΓΆzelebbi piac volt az amerikai r hernΓ‘di judit lΓ‘nya csalΓ‘djΓ‘hoz tartozΓ³ veb kranbau hennigsdo...az Γreket a belΓΌl fΓ©lprΓm kanonikus alakja a turistaΓΊt mellett tΓ‘madhatΓ³k Γ‘m kΓ©sΕbb v vlagyimir ilji...Γ©s a krasznojarszki hatΓ‘rterΓΌlet melybΕl rΓ³mai korbΓ³l ugyanis a kerlΓ©s beszterce naszΓ³d vΓ‘rmegyΓ©hez ...
Context Size 2:
Γ©s a vΓ©rlemezke szΓ‘m vizsgΓ‘latok az eklampsiasok vΓ©rΓ©nek calciumion concentratiΓ³jΓ‘rΓ³l bodΓ³ richΓ‘rdda...hogy a tΓ‘bornagy unokΓ‘ja teschen harmadik hercegΓ©nek Γ©s aragΓ³niai nyelven nyelvjΓ‘rΓ‘sban Γxar bΓ‘rΓ³ja ...tovΓ‘bbi informΓ‘ciΓ³k gΓΆrΓΆg irodalom tΓΆrtΓ©nete athenaeum november 4 a aguja km 279 36 32 53 2 45
Context Size 3:
jegyzetek tovΓ‘bbi informΓ‘ciΓ³k szΓnΓ©szek szΓΌletett szemΓ©lyek szemΓ©lyek szΓnΓ©sznΕk humoristΓ‘k york iak...nΓ©pessΓ©g a telepΓΌlΓ©s nΓ©pessΓ©ge az elmΓΊlt Γ©vekben az alΓ‘bbi mΓ³don vΓ‘ltozott jegyzetek tovΓ‘bbi informΓ‘...szΓΌletett szemΓ©lyek elhunyt szemΓ©lyek becsΓΌletrend lovagjai tΓ‘rcaΓrΓ³k szΓ‘rmazΓ‘sΓΊ magyarok emigrΓ‘nsok...
Context Size 4:
szΓΌletett szemΓ©lyek elhunyt szemΓ©lyek nΕk eurovΓziΓ³s dalfesztivΓ‘l pontbejelentΕia telepΓΌlΓ©s nΓ©pessΓ©gΓ©nek vΓ‘ltozΓ‘sa jegyzetek tovΓ‘bbi informΓ‘ciΓ³k telepΓΌlΓ©sei lΓ©trehozott spanyol tel...nΓ©pessΓ©g a telepΓΌlΓ©s nΓ©pessΓ©gΓ©nek vΓ‘ltozΓ‘sa jegyzetek tovΓ‘bbi informΓ‘ciΓ³k megye telepΓΌlΓ©sei lΓ©trehoz...
Generated Text Samples (Subword-based)
Below are text samples generated from each subword-based Markov chain model:
Context Size 1:
_bΓ³dΓ‘mΕ±vΓ‘lla_Γ©m_etotΓ©spa_mΓ©gΓ³ncsapcigyla_em_k)_h
Context Size 2:
_avallΓ©s_ma_akasza_+_cΓ©letΕbbeild.szettΓ‘raminterico
Context Size 3:
_a_tor_anni_volsen_szΓ³lΓ³sΓtΓ‘sai_form_az_amika_vΓ©gzeti_
Context Size 4:
_az_le_a_muzsikus_b_Γ©s_4-i_egyet_Γ©rkez_egy_kir._idΕs_diss
Key Findings
- Best Predictability: Context-4 (word) with 95.2% predictability
- Branching Factor: Decreases with context size (more deterministic)
- Memory Trade-off: Larger contexts require more storage (2,950,554 contexts)
- Recommendation: Context-3 or Context-4 for text generation
4. Vocabulary Analysis
Statistics
| Metric | Value |
|---|---|
| Vocabulary Size | 2,314,804 |
| Total Tokens | 210,700,540 |
| Mean Frequency | 91.02 |
| Median Frequency | 4 |
| Frequency Std Dev | 11249.15 |
Most Common Words
| Rank | Word | Frequency |
|---|---|---|
| 1 | a | 15,266,391 |
| 2 | az | 4,841,770 |
| 3 | Γ©s | 4,422,301 |
| 4 | is | 1,350,461 |
| 5 | egy | 1,181,563 |
| 6 | hogy | 978,556 |
| 7 | volt | 963,293 |
| 8 | 1 | 909,318 |
| 9 | nem | 804,148 |
| 10 | 2 | 677,083 |
Least Common Words (from vocabulary)
| Rank | Word | Frequency |
|---|---|---|
| 1 | vichyvel | 2 |
| 2 | ftpf | 2 |
| 3 | hakeimi | 2 |
| 4 | ixkun | 2 |
| 5 | demannt | 2 |
| 6 | summercamp | 2 |
| 7 | madguy | 2 |
| 8 | meisterleistung | 2 |
| 9 | copΓn | 2 |
| 10 | transparentete | 2 |
Zipf's Law Analysis
| Metric | Value |
|---|---|
| Zipf Coefficient | 0.9342 |
| RΒ² (Goodness of Fit) | 0.996484 |
| Adherence Quality | excellent |
Coverage Analysis
| Top N Words | Coverage |
|---|---|
| Top 100 | 25.6% |
| Top 1,000 | 45.5% |
| Top 5,000 | 61.8% |
| Top 10,000 | 69.0% |
Key Findings
- Zipf Compliance: RΒ²=0.9965 indicates excellent adherence to Zipf's law
- High Frequency Dominance: Top 100 words cover 25.6% of corpus
- Long Tail: 2,304,804 words needed for remaining 31.0% 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 | 0.7896 | 0.3549 | N/A | N/A |
| mono_64d | 64 | 0.7843 | 0.2900 | N/A | N/A |
| mono_128d | 128 | 0.7205 | 0.2280 | N/A | N/A |
| aligned_32d | 32 | 0.7896 π | 0.3731 | 0.3780 | 0.7580 |
| aligned_64d | 64 | 0.7843 | 0.2877 | 0.5600 | 0.8860 |
| aligned_128d | 128 | 0.7205 | 0.2242 | 0.7160 | 0.9400 |
Key Findings
- Best Isotropy: aligned_32d with 0.7896 (more uniform distribution)
- Semantic Density: Average pairwise similarity of 0.2930. Lower values indicate better semantic separation.
- Alignment Quality: Aligned models achieve up to 71.6% 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 | -0.542 | 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 |
|---|---|
-s |
szedhessΓ©k, sejttΓpusban, szemszΓnΕ± |
-k |
kΓ³borlΓ³nak, kΕalappal, kΓΌldetΓ©seikben |
-m |
meklΔt, morarano, megbΓΌntethettΓ©k |
-a |
ammaniti, aurignacian, aranybaglyok |
-t |
tagkΓ©nt, tΓ‘vhΕtermelΕ, terepviszony |
-b |
bolondozott, buga, birkΓ³zΓ‘ssal |
-ma |
manbij, macham, magΓ‘nszΓnhΓ‘zakban |
-e |
elaborate, elitegyetemek, eugène |
Productive Suffixes
| Suffix | Examples |
|---|---|
-t |
cserΓ©phΓ©jazat, tagkΓ©nt, irritΓ‘ciΓ³kat |
-k |
kΓ³borlΓ³nak, Γ©rbetegsΓ©gek, szedhessΓ©k |
-n |
vardaman, pihenΕhelyΓΌkΓΆn, sejttΓpusban |
-a |
hera, buga, philosophya |
-l |
hurbΓ³l, lavel, vranishtnΓ‘l |
-s |
francoizmus, nativizΓ‘lΓ‘s, ΓΆndiagnΓ³zis |
-i |
ammaniti, lendvai, diΓ³falvi |
-e |
elaborate, piauiense, eugène |
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 |
|---|---|---|---|
mber |
1.61x | 605 contexts | ember, umber, Γ‘mber |
epΓΌl |
1.89x | 164 contexts | repΓΌl, repΓΌle, repΓΌlΕ |
erΓΌl |
1.60x | 344 contexts | terΓΌl, kerΓΌl, merΓΌl |
ΓΆrtΓ© |
2.09x | 79 contexts | tΓΆrtΓ©, kΓΆrtΓ©s, sΓΆrtΓ©i |
ΓΌlet |
1.50x | 362 contexts | fΓΌlet, szΓΌlet, ΓzΓΌlet |
atΓ‘s |
1.41x | 443 contexts | katΓ‘s, fatΓ‘s, hatΓ‘s |
rtΓ©n |
2.05x | 57 contexts | artΓ©n, Γ©rtΓ©ny, tΓΆrtΓ©n |
Γtot |
1.62x | 161 contexts | Γtott, sΓtott, vΓtott |
ΓtΓ‘s |
1.38x | 376 contexts | sΓtΓ‘s, ΓΊjΓtΓ‘s, Γ‘mΓtΓ‘s |
ormΓ‘ |
1.46x | 267 contexts | ormΓ‘n, ormΓ‘t, dormΓ‘n |
alΓ‘l |
1.43x | 226 contexts | talΓ‘l, halΓ‘l, valΓ‘l |
lepΓΌ |
2.81x | 14 contexts | telepΓΌ, telepΓΌk, telepΓΌl |
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 |
|---|---|---|---|
-k |
-k |
118 words | kinyissanak, konowalik |
-s |
-t |
87 words | szvetlΓ‘nΓ‘t, szkΓ‘dit |
-k |
-t |
84 words | konceptalbumokat, kevesebbΓ©rt |
-k |
-l |
84 words | kΓ‘rtyacsomagokkal, karmΓ‘rΓ³l |
-s |
-l |
84 words | szΓ©nΓΌl, szΕnyeggyΓ‘rbΓ³l |
-s |
-k |
81 words | sΓ³raktΓ‘rnak, szΓ‘molhatnΓ‘nk |
-s |
-n |
80 words | sarrewerden, sumbawΓ‘n |
-s |
-a |
77 words | sserunkuma, sztalina |
-k |
-a |
77 words | kruczynska, kivΓ©telszΓ‘mba |
-m |
-k |
75 words | manhunterek, megbetegedΓ©seik |
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 |
|---|---|---|---|
| csalΓ‘dira | csalΓ‘d-i-ra |
7.5 | i |
| xantofilek | xantofi-l-ek |
7.5 | l |
| marinaviale | marinavi-al-e |
7.5 | al |
| castillΓ‘nak | castillΓ‘-n-ak |
7.5 | n |
| karakterjΓ©nek | karakterjΓ©-n-ek |
7.5 | n |
| kampΓ‘nystΓ‘bjΓ‘nak | kampΓ‘nystΓ‘bjΓ‘-n-ak |
7.5 | n |
| nyelveire | nyelve-i-re |
7.5 | i |
| tΓ‘vharcban | tΓ‘vharc-ba-n |
7.5 | ba |
| guadalcanalt | guadalcan-al-t |
7.5 | al |
| palesztΓnai | palesztΓn-a-i |
7.5 | a |
| idΓ©nymunkΓ‘kon | idΓ©nymunkΓ‘-k-on |
7.5 | k |
| kΓ©pzΕmΕ±vΓ©szeknek | kΓ©pzΕmΕ±vΓ©szek-n-ek |
7.5 | n |
| paakkanen | paakka-n-en |
7.5 | n |
| kΓΆrlapnak | kΓΆrlap-n-ak |
7.5 | n |
| fΓ©rfimunkΓ‘sok | fΓ©rfimunkΓ‘-s-ok |
7.5 | s |
6.6 Linguistic Interpretation
Automated Insight: The language Hungarian 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 (4.66x) |
| N-gram | 2-gram | Lowest perplexity (435) |
| Markov | Context-4 | Highest predictability (95.2%) |
| 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: 2026-01-13 20:45:23



















