Kara-Kalpak - Wikilangs Models
Comprehensive Research Report & Full Ablation Study
This repository contains NLP models trained and evaluated by Wikilangs, specifically on Kara-Kalpak 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 | 4.095x | 4.10 | 0.0535% | 1,035,724 |
| 16k | 4.571x | 4.57 | 0.0597% | 927,895 |
| 32k | 4.952x | 4.95 | 0.0647% | 856,500 |
| 64k | 5.231x π | 5.23 | 0.0683% | 810,783 |
Tokenization Examples
Below are sample sentences tokenized with each vocabulary size:
Sample 1: BobrovΔ±tsΓ’ () β UkrainanΔ±Ε Chernigov wΓ‘layatΔ±nda jaylasqan qala. BobrovΔ±tsa rayo...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | βbob r ov Δ±t s Γ’ β() ββ βukrain anΔ±Ε ... (+29 more) |
39 |
| 16k | βbob rov Δ±t s Γ’ β() ββ βukrainanΔ±Ε βchern ig ... (+26 more) |
36 |
| 32k | βbob rov Δ±t s Γ’ β() ββ βukrainanΔ±Ε βchern ig ... (+26 more) |
36 |
| 64k | βbobrovΔ±t s Γ’ β() ββ βukrainanΔ±Ε βchern ig ov βwΓ‘layatΔ±nda ... (+22 more) |
32 |
Sample 2: β QΔ±rΗ΅Δ±zstannΔ±Ε Osh wΓ‘layatΔ± Γlken-Alay rayonΔ±ndaΗ΅Δ± awΔ±l. Γlken-Alay APJ quramΔ±n...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | ββ βqΔ±rΗ΅Δ±zstannΔ±Ε βosh βwΓ‘layatΔ± βΓΊlken - alay βrayonΔ±ndaΗ΅Δ± βawΔ±l . ... (+19 more) |
29 |
| 16k | ββ βqΔ±rΗ΅Δ±zstannΔ±Ε βosh βwΓ‘layatΔ± βΓΊlken - alay βrayonΔ±ndaΗ΅Δ± βawΔ±l . ... (+19 more) |
29 |
| 32k | ββ βqΔ±rΗ΅Δ±zstannΔ±Ε βosh βwΓ‘layatΔ± βΓΊlken - alay βrayonΔ±ndaΗ΅Δ± βawΔ±l . ... (+19 more) |
29 |
| 64k | ββ βqΔ±rΗ΅Δ±zstannΔ±Ε βosh βwΓ‘layatΔ± βΓΊlken - alay βrayonΔ±ndaΗ΅Δ± βawΔ±l . ... (+19 more) |
29 |
Sample 3: β QΔ±rΗ΅Δ±zstannΔ±Ε Batken wΓ‘layatΔ± Qadamjay rayonΔ±ndaΗ΅Δ± awΔ±l. AwΔ±l Maydan awΔ±l okru...
| Vocab | Tokens | Count |
|---|---|---|
| 8k | ββ βqΔ±rΗ΅Δ±zstannΔ±Ε βbatken βwΓ‘layatΔ± βqadamjay βrayonΔ±ndaΗ΅Δ± βawΔ±l . βawΔ±l βmaydan ... (+19 more) |
29 |
| 16k | ββ βqΔ±rΗ΅Δ±zstannΔ±Ε βbatken βwΓ‘layatΔ± βqadamjay βrayonΔ±ndaΗ΅Δ± βawΔ±l . βawΔ±l βmaydan ... (+19 more) |
29 |
| 32k | ββ βqΔ±rΗ΅Δ±zstannΔ±Ε βbatken βwΓ‘layatΔ± βqadamjay βrayonΔ±ndaΗ΅Δ± βawΔ±l . βawΔ±l βmaydan ... (+19 more) |
29 |
| 64k | ββ βqΔ±rΗ΅Δ±zstannΔ±Ε βbatken βwΓ‘layatΔ± βqadamjay βrayonΔ±ndaΗ΅Δ± βawΔ±l . βawΔ±l βmaydan ... (+19 more) |
29 |
Key Findings
- Best Compression: 64k achieves 5.231x compression
- Lowest UNK Rate: 8k with 0.0535% 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 | 23,270 | 14.51 | 54,707 | 10.1% | 27.4% |
| 2-gram | Subword | 339 π | 8.41 | 4,784 | 62.1% | 98.8% |
| 3-gram | Word | 20,253 | 14.31 | 46,477 | 13.1% | 28.7% |
| 3-gram | Subword | 2,759 | 11.43 | 39,335 | 21.9% | 68.2% |
| 4-gram | Word | 25,858 | 14.66 | 61,893 | 14.2% | 28.0% |
| 4-gram | Subword | 13,674 | 13.74 | 197,359 | 11.1% | 37.3% |
| 5-gram | Word | 14,234 | 13.80 | 37,066 | 17.5% | 35.1% |
| 5-gram | Subword | 43,260 | 15.40 | 503,495 | 6.5% | 24.7% |
Top 5 N-grams by Size
2-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | sonday aq |
3,034 |
| 2 | menen birge |
2,841 |
| 3 | bolΔ±p tabΔ±ladΔ± |
2,616 |
| 4 | sΔ±rtqΔ± siltemeler |
2,295 |
| 5 | bir neshe |
2,269 |
3-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | derekler sΔ±rtqΔ± siltemeler |
1,685 |
| 2 | lΓ©gales geografiyasΔ± jer |
1,398 |
| 3 | adampopulations lΓ©gales geografiyasΔ± |
1,398 |
| 4 | geografiyasΔ± jer maydanΔ± |
1,374 |
| 5 | sonΔ±Ε menen birge |
1,344 |
4-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | adampopulations lΓ©gales geografiyasΔ± jer |
1,398 |
| 2 | lΓ©gales geografiyasΔ± jer maydanΔ± |
1,374 |
| 3 | jaylasqan kommuna xalqΔ± xalqΔ± |
1,319 |
| 4 | sΔ±rtqΔ± siltemeler departamenti kommunalarΔ± |
1,319 |
| 5 | derekler sΔ±rtqΔ± siltemeler departamenti |
1,318 |
5-grams (Word):
| Rank | N-gram | Count |
|---|---|---|
| 1 | adampopulations lΓ©gales geografiyasΔ± jer maydanΔ± |
1,374 |
| 2 | departamentinde jaylasqan kommuna xalqΔ± xalqΔ± |
1,318 |
| 3 | derekler sΔ±rtqΔ± siltemeler departamenti kommunalarΔ± |
1,318 |
| 4 | km2 derekler sΔ±rtqΔ± siltemeler departamenti |
1,317 |
| 5 | franciyanΔ±Ε seine maritime departamentinde jaylasqan |
707 |
2-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | a r |
340,214 |
| 2 | l a |
332,558 |
| 3 | a n |
303,317 |
| 4 | n _ |
291,907 |
| 5 | a _ |
281,704 |
3-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | l a r |
145,814 |
| 2 | a n _ |
91,773 |
| 3 | l e r |
91,522 |
| 4 | i y a |
90,612 |
| 5 | _ h Γ‘ |
90,529 |
4-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ h Γ‘ m |
74,987 |
| 2 | h Γ‘ m _ |
73,954 |
| 3 | l a r Δ± |
52,831 |
| 4 | Δ± n d a |
52,080 |
| 5 | l Δ± q _ |
47,017 |
5-grams (Subword):
| Rank | N-gram | Count |
|---|---|---|
| 1 | _ h Γ‘ m _ |
73,759 |
| 2 | Δ± n d a _ |
37,981 |
| 3 | a l Δ± q _ |
26,249 |
| 4 | a d Δ± . _ |
25,896 |
| 5 | e n e n _ |
25,107 |
Key Findings
- Best Perplexity: 2-gram (subword) with 339
- Entropy Trend: Decreases with larger n-grams (more predictable)
- Coverage: Top-1000 patterns cover ~25% 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 | 0.9475 | 1.928 | 7.14 | 215,380 | 5.3% |
| 1 | Subword | 0.9483 | 1.930 | 8.43 | 1,371 | 5.2% |
| 2 | Word | 0.2249 | 1.169 | 1.49 | 1,535,314 | 77.5% |
| 2 | Subword | 1.0052 | 2.007 | 6.59 | 11,538 | 0.0% |
| 3 | Word | 0.0563 | 1.040 | 1.09 | 2,281,857 | 94.4% |
| 3 | Subword | 0.8603 | 1.815 | 4.43 | 75,969 | 14.0% |
| 4 | Word | 0.0154 π | 1.011 | 1.02 | 2,476,994 | 98.5% |
| 4 | Subword | 0.6640 | 1.584 | 2.96 | 336,428 | 33.6% |
Generated Text Samples (Word-based)
Below are text samples generated from each word-based Markov chain model:
Context Size 1:
hΓ‘m oqΔ±w orΔ±nlarΔ± la capital hΓ‘m jazΔ±wdΔ± buyΔ±rΔ±w sistemasΔ±nan wear os 1 1 sΔ±yaqlΔ± uluwmalΔ±q yamasamenen baylanΔ±s kanallarΔ±n usΔ±nΗ΅an sorawlarΔ± jiberiletuΗ΅Δ±n reklamalardΔ± alΔ±p keledi generikler c php ...ushΔ±n paydalanΔ±ladΔ± Γ³ytkeni biraq bul kompilyatorΗ΅a tΓ‘n juwap beriw jolΔ± qol menen qatnasqan hΓ‘m mΓ‘d...
Context Size 2:
sonday aq aldΔ±ΕΗ΅Δ± qosΔ±qlarΔ±nΔ±Ε tariyxΔ±n izertley aladΔ± internet protokolΔ± 4 versiyasΔ± ipv4 ip adresi...menen birge orΔ±nlanatuΗ΅Δ±n programma kerek Γ³ytkeni Γ‘jiniyazΗ΅a shekemgi qaraqalpaq shayΔ±rlarΔ±nda bul f...bolΔ±p tabΔ±ladΔ± bes juldΔ±z berip dosΔ±nΔ±Ε mΔ±na sΓ³zlerin keltiredi windows api sonshelli keΕ tarqaldΔ± b...
Context Size 3:
derekler sΔ±rtqΔ± siltemeler departamenti kommunalarΔ±lΓ©gales geografiyasΔ± jer maydanΔ± 20 49 km2 derekler sΔ±rtqΔ± siltemeler departamenti kommunalarΔ±adampopulations lΓ©gales geografiyasΔ± jer maydanΔ± 19 09 km2 derekler sΔ±rtqΔ± siltemeler departamenti k...
Context Size 4:
adampopulations lΓ©gales geografiyasΔ± jer maydanΔ± 14 37 km2 derekler sΔ±rtqΔ± siltemeler departamenti k...lΓ©gales geografiyasΔ± jer maydanΔ± 5 55 km2 derekler sΔ±rtqΔ± siltemeler departamenti kommunalarΔ±jaylasqan kommuna xalqΔ± xalqΔ± 2 635 adampopulations lΓ©gales geografiyasΔ± jer maydanΔ± 17 47 km2 derek...
Generated Text Samples (Subword-based)
Below are text samples generated from each subword-based Markov chain model:
Context Size 1:
_qΔ±n_ticenendayaa_1460_deberoliyidayamgi_β_p_tia
Context Size 2:
arΔ±n_dΓ‘willadΔ±_dolar_twajlarΔ±_dΓ‘_sanlatΔ±nΗ΅an_ionΔ±Ε_
Context Size 3:
lar_bazlΔ±q_derek,_an_ashqada_basΔ±ndaiyatlar_bolΔ±wΔ±_anΔ±
Context Size 4:
_hΓ‘m_ol_hasΔ±_qatnashΓ‘m_g_sui_skepti_deΔ±nda_kΓ³terilgerisiw
Key Findings
- Best Predictability: Context-4 (word) with 98.5% predictability
- Branching Factor: Decreases with context size (more deterministic)
- Memory Trade-off: Larger contexts require more storage (336,428 contexts)
- Recommendation: Context-3 or Context-4 for text generation
4. Vocabulary Analysis
Statistics
| Metric | Value |
|---|---|
| Vocabulary Size | 94,344 |
| Total Tokens | 2,550,053 |
| Mean Frequency | 27.03 |
| Median Frequency | 4 |
| Frequency Std Dev | 320.88 |
Most Common Words
| Rank | Word | Frequency |
|---|---|---|
| 1 | hΓ‘m | 74,114 |
| 2 | menen | 22,644 |
| 3 | ushΔ±n | 19,490 |
| 4 | bul | 18,802 |
| 5 | bir | 13,691 |
| 6 | ol | 12,270 |
| 7 | bolΔ±p | 9,798 |
| 8 | yamasa | 8,778 |
| 9 | bolΗ΅an | 8,505 |
| 10 | dep | 8,012 |
Least Common Words (from vocabulary)
| Rank | Word | Frequency |
|---|---|---|
| 1 | allaxabad | 2 |
| 2 | shaqapshasΔ±na | 2 |
| 3 | pondar | 2 |
| 4 | shechen | 2 |
| 5 | Γ‘limsultanov | 2 |
| 6 | alimsultanovtΔ±Ε | 2 |
| 7 | xasavyurt | 2 |
| 8 | Εebinkarahisar | 2 |
| 9 | 042 | 2 |
| 10 | iΜzel | 2 |
Zipf's Law Analysis
| Metric | Value |
|---|---|
| Zipf Coefficient | 0.9824 |
| RΒ² (Goodness of Fit) | 0.989215 |
| Adherence Quality | excellent |
Coverage Analysis
| Top N Words | Coverage |
|---|---|
| Top 100 | 21.4% |
| Top 1,000 | 49.2% |
| Top 5,000 | 71.8% |
| Top 10,000 | 80.5% |
Key Findings
- Zipf Compliance: RΒ²=0.9892 indicates excellent adherence to Zipf's law
- High Frequency Dominance: Top 100 words cover 21.4% of corpus
- Long Tail: 84,344 words needed for remaining 19.5% 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 | 0.8596 π | 0.3821 | N/A | N/A |
| mono_64d | 64 | 0.8357 | 0.2373 | N/A | N/A |
| mono_128d | 128 | 0.8393 | 0.1678 | N/A | N/A |
| aligned_32d | 32 | 0.8596 | 0.3758 | 0.0640 | 0.2900 |
| aligned_64d | 64 | 0.8357 | 0.2292 | 0.1320 | 0.4080 |
| aligned_128d | 128 | 0.8393 | 0.1697 | 0.1560 | 0.4740 |
Key Findings
- Best Isotropy: mono_32d with 0.8596 (more uniform distribution)
- Semantic Density: Average pairwise similarity of 0.2603. Lower values indicate better semantic separation.
- Alignment Quality: Aligned models achieve up to 15.6% 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 | 0.422 | 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 |
|---|---|
-s |
sovxozΔ±, sibirdiΕ, shakuriy |
-a |
arturo, adewir, aΗ΅asΔ± |
-t |
toplaydΔ±, talantΔ±n, tΓΊsiminiΕ |
-b |
besten, barri, bahalΔ± |
-k |
komandiriniΕ, kaliforniyada, komponentleri |
-m |
mamanlΔ±Η΅Δ±, mellanox, materigin |
-ma |
mamanlΔ±Η΅Δ±, materigin, makbet |
-sh |
shakuriy, shΔ±Η΅Δ±r, shtatΔ± |
Productive Suffixes
| Suffix | Examples |
|---|---|
-n |
dawamΔ±n, daΗ΅darΔ±sΔ±n, besten |
-a |
kaliforniyada, Δ±qlΔ±mΔ±na, evropaΗ΅a |
-Δ± |
mamanlΔ±Η΅Δ±, toplaydΔ±, sovxozΔ± |
-Ε |
komandiriniΕ, sibirdiΕ, oppengeymernΔ±Ε |
-Δ±Ε |
oppengeymernΔ±Ε, dΓ‘rwazamanlardΔ±Ε, klarustΔ±Ε |
-i |
rsetti, komponentleri, xarakterlewshi |
-an |
aspan, gΓΊmannan, saban |
-r |
populyar, ΓΊstinler, adewir |
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 |
|---|---|---|---|
lard |
1.63x | 167 contexts | larda, lardΔ±, alardΔ± |
atla |
1.64x | 122 contexts | atlas, atlan, atlar |
tler |
1.65x | 98 contexts | etler, bitler, pΓ‘tler |
asΔ±n |
1.45x | 170 contexts | basΔ±n, pasΔ±n, tasΔ±n |
ardΔ± |
1.86x | 47 contexts | yardΔ±, bardΔ±, lardΔ± |
ayla |
1.45x | 107 contexts | layla, aylar, zayla |
shΔ±l |
1.74x | 47 contexts | aqshΔ±l, shΔ±lΔ±m, oyshΔ±l |
alΔ±q |
1.41x | 104 contexts | xalΔ±q, salΔ±q, balΔ±q |
tuΗ΅Δ± |
2.22x | 18 contexts | tuΗ΅Δ±n, atatuΗ΅Δ±n, Γ³tetuΗ΅Δ±n |
wshΔ± |
1.85x | 30 contexts | suwshΔ±, oyΔ±wshΔ±, oqΔ±wshΔ± |
ciya |
1.76x | 34 contexts | raciya, akciya, faciya |
ladΔ± |
1.61x | 47 contexts | aladΔ±, oyladΔ±, aqladΔ± |
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 |
|---|---|---|---|
-s |
-a |
140 words | sozΔ±lΔ±wΗ΅a, samaveda |
-s |
-n |
123 words | sportΔ±n, sedan |
-a |
-Δ± |
109 words | alΔ±ndΔ±, aleksandriyalΔ± |
-k |
-i |
104 words | kΓΊndizgi, keΕeytpeni |
-a |
-n |
97 words | aΕlatpaytuΗ΅Δ±nΔ±n, australian |
-b |
-n |
95 words | bΓ‘hΓ‘rinen, baylanΔ±sΔ±wΔ±nan |
-s |
-Δ± |
94 words | sΔ±rtqΔ±, sawatlΔ± |
-t |
-Δ± |
94 words | tartΔ±sΔ±wlardΔ±, tulΔ± |
-t |
-n |
92 words | talqΔ±laΗ΅an, turatuΗ΅Δ±nΔ±n |
-a |
-a |
88 words | albina, auditoriyasΔ±na |
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 |
|---|---|---|---|
| vetnamnΔ±Ε | vetnam-n-Δ±Ε |
7.5 | n |
| raketalardΔ± | raketal-ar-dΔ± |
7.5 | ar |
| bruklindaΗ΅Δ± | bruklin-da-Η΅Δ± |
7.5 | da |
| waqΔ±yadan | waqΔ±ya-da-n |
7.5 | da |
| freymvorklarΔ± | freymvorkl-ar-Δ± |
7.5 | ar |
| galitsina | galitsi-n-a |
7.5 | n |
| futbolshΔ±lardΔ± | futbolshΔ±l-ar-dΔ± |
7.5 | ar |
| kolonnasΔ± | kolon-na-sΔ± |
7.5 | na |
| redaktorlarda | redaktorl-ar-da |
7.5 | ar |
| sanktgallendaΗ΅Δ± | sanktgallen-da-Η΅Δ± |
7.5 | da |
| abdujalil | abdujal-i-l |
7.5 | i |
| singllarΔ±n | singll-ar-Δ±n |
7.5 | ar |
| zanjibarda | zanjib-ar-da |
7.5 | ar |
| kΓ³ringenindey | kΓ³ringenin-de-y |
7.5 | de |
| nuqsanlarΔ±n | nuqsanl-ar-Δ±n |
7.5 | ar |
6.6 Linguistic Interpretation
Automated Insight: The language Kara-Kalpak 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 (5.23x) |
| N-gram | 2-gram | Lowest perplexity (339) |
| Markov | Context-4 | Highest predictability (98.5%) |
| 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: 2026-01-10 07:05:40



















