--- language: ab language_name: Abkhazian language_family: caucasian_northwest tags: - wikilangs - nlp - tokenizer - embeddings - n-gram - markov - wikipedia - feature-extraction - sentence-similarity - tokenization - n-grams - markov-chain - text-mining - fasttext - babelvec - vocabulous - vocabulary - monolingual - family-caucasian_northwest license: mit library_name: wikilangs pipeline_tag: text-generation datasets: - omarkamali/wikipedia-monthly dataset_info: name: wikipedia-monthly description: Monthly snapshots of Wikipedia articles across 300+ languages metrics: - name: best_compression_ratio type: compression value: 4.193 - name: best_isotropy type: isotropy value: 0.8394 - name: vocabulary_size type: vocab value: 0 generated: 2026-01-03 --- # Abkhazian - Wikilangs Models ## Comprehensive Research Report & Full Ablation Study This repository contains NLP models trained and evaluated by Wikilangs, specifically on **Abkhazian** Wikipedia data. We analyze tokenizers, n-gram models, Markov chains, vocabulary statistics, and word embeddings. ## 📋 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 ![Performance Dashboard](visualizations/performance_dashboard.png) ### Analysis and Evaluation - [1. Tokenizer Evaluation](#1-tokenizer-evaluation) - [2. N-gram Model Evaluation](#2-n-gram-model-evaluation) - [3. Markov Chain Evaluation](#3-markov-chain-evaluation) - [4. Vocabulary Analysis](#4-vocabulary-analysis) - [5. Word Embeddings Evaluation](#5-word-embeddings-evaluation) - [6. Morphological Analysis (Experimental)](#6--morphological-analysis-experimental) - [7. Summary & Recommendations](#7-summary--recommendations) - [Metrics Glossary](#appendix-metrics-glossary--interpretation-guide) - [Visualizations Index](#visualizations-index) --- ## 1. Tokenizer Evaluation ![Tokenizer Compression](visualizations/tokenizer_compression.png) ![Tokenizer Fertility](visualizations/tokenizer_fertility.png) ![Tokenizer OOV](visualizations/tokenizer_oov.png) ![Total Tokens](visualizations/tokenizer_total_tokens.png) ### Results | Vocab Size | Compression | Avg Token Len | UNK Rate | Total Tokens | |------------|-------------|---------------|----------|--------------| | **8k** | 3.306x | 3.31 | 0.1493% | 223,032 | | **16k** | 3.654x | 3.66 | 0.1650% | 201,823 | | **32k** | 3.910x | 3.92 | 0.1766% | 188,563 | | **64k** | 4.193x 🏆 | 4.20 | 0.1893% | 175,871 | ### Tokenization Examples Below are sample sentences tokenized with each vocabulary size: **Sample 1:** `Ѳ, ѳ — кириллтәи аҩыратә архаикатә иажәхьоу нбан. Азхьарԥшқәа Graphemica (Ѳ) Gra...` | Vocab | Tokens | Count | |-------|--------|-------| | 8k | `▁ ѳ , ▁ ѳ ▁— ▁кириллтәи ▁аҩыратә ▁архаикатә ▁иажәхьоу ... (+11 more)` | 21 | | 16k | `▁ѳ , ▁ѳ ▁— ▁кириллтәи ▁аҩыратә ▁архаикатә ▁иажәхьоу ▁нбан . ... (+9 more)` | 19 | | 32k | `▁ѳ , ▁ѳ ▁— ▁кириллтәи ▁аҩыратә ▁архаикатә ▁иажәхьоу ▁нбан . ... (+9 more)` | 19 | | 64k | `▁ѳ , ▁ѳ ▁— ▁кириллтәи ▁аҩыратә ▁архаикатә ▁иажәхьоу ▁нбан . ... (+9 more)` | 19 | **Sample 2:** `Скуо-Уелли Winter Olympics, Jeux olympiques d'hiver de - аӡынтәи Олимпиадатә хәм...` | Vocab | Tokens | Count | |-------|--------|-------| | 8k | `▁с ку о - у елли ▁winter ▁olympics , ▁jeux ... (+12 more)` | 22 | | 16k | `▁с ку о - у елли ▁winter ▁olympics , ▁jeux ... (+12 more)` | 22 | | 32k | `▁с ку о - уелли ▁winter ▁olympics , ▁jeux ▁olympiques ... (+11 more)` | 21 | | 64k | `▁скуо - уелли ▁winter ▁olympics , ▁jeux ▁olympiques ▁d ' ... (+9 more)` | 19 | **Sample 3:** `Ж, ж — кириллтәи аҩыратә нбан. Азхьарԥшқәа Graphemica (Ж) Graphemica (ж)` | Vocab | Tokens | Count | |-------|--------|-------| | 8k | `▁ж , ▁ж ▁— ▁кириллтәи ▁аҩыратә ▁нбан . ▁азхьарԥшқәа ▁graphemica ... (+7 more)` | 17 | | 16k | `▁ж , ▁ж ▁— ▁кириллтәи ▁аҩыратә ▁нбан . ▁азхьарԥшқәа ▁graphemica ... (+7 more)` | 17 | | 32k | `▁ж , ▁ж ▁— ▁кириллтәи ▁аҩыратә ▁нбан . ▁азхьарԥшқәа ▁graphemica ... (+7 more)` | 17 | | 64k | `▁ж , ▁ж ▁— ▁кириллтәи ▁аҩыратә ▁нбан . ▁азхьарԥшқәа ▁graphemica ... (+7 more)` | 17 | ### Key Findings - **Best Compression:** 64k achieves 4.193x compression - **Lowest UNK Rate:** 8k with 0.1493% 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 ![N-gram Perplexity](visualizations/ngram_perplexity.png) ![N-gram Unique](visualizations/ngram_unique.png) ![N-gram Coverage](visualizations/ngram_coverage.png) ### Results | N-gram | Variant | Perplexity | Entropy | Unique N-grams | Top-100 Coverage | Top-1000 Coverage | |--------|---------|------------|---------|----------------|------------------|-------------------| | **2-gram** | Word | 723 | 9.50 | 5,814 | 51.5% | 72.0% | | **2-gram** | Subword | 363 | 8.51 | 4,117 | 60.3% | 96.8% | | **3-gram** | Word | 252 | 7.98 | 5,218 | 66.6% | 80.6% | | **3-gram** | Subword | 2,678 | 11.39 | 28,284 | 28.1% | 67.5% | | **4-gram** | Word | 341 | 8.41 | 9,794 | 64.0% | 74.0% | | **4-gram** | Subword | 11,104 | 13.44 | 112,814 | 16.8% | 44.7% | | **5-gram** | Word | 198 🏆 | 7.63 | 7,301 | 69.5% | 78.6% | | **5-gram** | Subword | 26,131 | 14.67 | 211,528 | 13.8% | 34.5% | ### Top 5 N-grams by Size **2-grams (Word):** | Rank | N-gram | Count | |------|--------|-------| | 1 | `рыԥсҭазаара иалҵит` | 3,971 | | 2 | `иит рыԥсҭазаара` | 3,938 | | 3 | `рашәарамза ԥхынгәымза` | 3,603 | | 4 | `жәабранмза хәажәкырамза` | 3,603 | | 5 | `цәыббрамза жьҭаарамза` | 3,602 | **3-grams (Word):** | Rank | N-gram | Count | |------|--------|-------| | 1 | `иит рыԥсҭазаара иалҵит` | 3,938 | | 2 | `цәыббрамза жьҭаарамза абҵарамза` | 3,602 | | 3 | `нанҳәамза цәыббрамза жьҭаарамза` | 3,601 | | 4 | `жьҭаарамза абҵарамза ԥхынҷкәынмза` | 3,601 | | 5 | `лаҵарамза рашәарамза ԥхынгәымза` | 3,601 | **4-grams (Word):** | Rank | N-gram | Count | |------|--------|-------| | 1 | `цәыббрамза жьҭаарамза абҵарамза ԥхынҷкәынмза` | 3,601 | | 2 | `нанҳәамза цәыббрамза жьҭаарамза абҵарамза` | 3,601 | | 3 | `ԥхынгәымза нанҳәамза цәыббрамза жьҭаарамза` | 3,601 | | 4 | `мшаԥымза лаҵарамза рашәарамза ԥхынгәымза` | 3,601 | | 5 | `лаҵарамза рашәарамза ԥхынгәымза нанҳәамза` | 3,601 | **5-grams (Word):** | Rank | N-gram | Count | |------|--------|-------| | 1 | `мшаԥымза лаҵарамза рашәарамза ԥхынгәымза нанҳәамза` | 3,601 | | 2 | `рашәарамза ԥхынгәымза нанҳәамза цәыббрамза жьҭаарамза` | 3,601 | | 3 | `ԥхынгәымза нанҳәамза цәыббрамза жьҭаарамза абҵарамза` | 3,601 | | 4 | `нанҳәамза цәыббрамза жьҭаарамза абҵарамза ԥхынҷкәынмза` | 3,601 | | 5 | `лаҵарамза рашәарамза ԥхынгәымза нанҳәамза цәыббрамза` | 3,601 | **2-grams (Subword):** | Rank | N-gram | Count | |------|--------|-------| | 1 | `а _` | 154,936 | | 2 | `_ а` | 150,057 | | 3 | `р а` | 100,657 | | 4 | `а р` | 84,729 | | 5 | `ә а` | 76,114 | **3-grams (Subword):** | Rank | N-gram | Count | |------|--------|-------| | 1 | `а р а` | 50,339 | | 2 | `м з а` | 45,875 | | 3 | `з а _` | 44,872 | | 4 | `а _ а` | 35,534 | | 5 | `а м з` | 31,361 | **4-grams (Subword):** | Rank | N-gram | Count | |------|--------|-------| | 1 | `м з а _` | 44,438 | | 2 | `а м з а` | 30,790 | | 3 | `р а м з` | 22,745 | | 4 | `а р а _` | 19,530 | | 5 | `қ ә а _` | 17,562 | **5-grams (Subword):** | Rank | N-gram | Count | |------|--------|-------| | 1 | `а м з а _` | 29,604 | | 2 | `р а м з а` | 22,366 | | 3 | `а р а м з` | 15,138 | | 4 | `т ә и _ а` | 11,926 | | 5 | `а қ ә а _` | 9,350 | ### Key Findings - **Best Perplexity:** 5-gram (word) with 198 - **Entropy Trend:** Decreases with larger n-grams (more predictable) - **Coverage:** Top-1000 patterns cover ~34% of corpus - **Recommendation:** 4-gram or 5-gram for best predictive performance --- ## 3. Markov Chain Evaluation ![Markov Entropy](visualizations/markov_entropy.png) ![Markov Contexts](visualizations/markov_contexts.png) ![Markov Branching](visualizations/markov_branching.png) ### Results | Context | Variant | Avg Entropy | Perplexity | Branching Factor | Unique Contexts | Predictability | |---------|---------|-------------|------------|------------------|-----------------|----------------| | **1** | Word | 0.6658 | 1.586 | 3.61 | 90,782 | 33.4% | | **1** | Subword | 1.3353 | 2.523 | 10.79 | 879 | 0.0% | | **2** | Word | 0.1206 | 1.087 | 1.22 | 327,437 | 87.9% | | **2** | Subword | 1.0094 | 2.013 | 5.94 | 9,477 | 0.0% | | **3** | Word | 0.0294 | 1.021 | 1.04 | 397,532 | 97.1% | | **3** | Subword | 0.7766 | 1.713 | 3.69 | 56,288 | 22.3% | | **4** | Word | 0.0100 🏆 | 1.007 | 1.01 | 413,065 | 99.0% | | **4** | Subword | 0.5281 | 1.442 | 2.33 | 207,598 | 47.2% | ### Generated Text Samples (Word-based) Below are text samples generated from each word-based Markov chain model: **Context Size 1:** 1. `уи зыхҟьаз зеиҧш дыҟамыз аҧҳәызба ссир иргылеит еидҵоу қырҭтәыла адемократиатә хдырра асоциалтә хьча...` 2. `рыԥсҭазаара иалҵит пиотр актәи амаӡаныҟәгаҩыс ш вуковар vukovar jedna prica ш азхьарԥшқәа heritagesi...` 3. `иит рыԥсҭазаара иалҵит кринагор абырзен бызшәа афранцыз италиа иалаигалоит флоренцианӡагьы инеиуеит ...` **Context Size 2:** 1. `иит рыԥсҭазаара иалҵит октавиан август аԥеиԥа диит ҳ ҟ 326 мцхеҭа ҳ ҟ 14 ш абанктә система` 2. `жәабранмза хәажәкырамза мшаԥымза лаҵарамза рашәарамза ԥхынгәымза нанҳәамза цәыббрамза жьҭаарамза абҵ...` 3. `рашәарамза ԥхынгәымза нанҳәамза цәыббрамза жьҭаарамза абҵарамза ԥхынҷкәынмза иит рыԥсҭазаара иалҵит ...` **Context Size 3:** 1. `цәыббрамза жьҭаарамза абҵарамза ԥхынҷкәынмза иит рыԥсҭазаара иалҵит аныҳәақәа араԥтә ар амш аҳәаахьч...` 2. `жьҭаарамза абҵарамза ԥхынҷкәынмза иит рыԥсҭазаара иалҵит аныҳәақәа араԥтә ар амш аҳәаахьчаҩцәа рамш ...` 3. `ажьырныҳәамза жәабранмза хәажәкырамза мшаԥымза лаҵарамза рашәарамза ԥхынгәымза нанҳәамза цәыббрамза ...` **Context Size 4:** 1. `цәыббрамза жьҭаарамза абҵарамза ԥхынҷкәынмза иит рыԥсҭазаара иалҵит клавдиа пульхра римтәи аамсҭаԥхә...` 2. `лаҵарамза рашәарамза ԥхынгәымза нанҳәамза цәыббрамза жьҭаарамза абҵарамза ԥхынҷкәынмза иит рыԥсҭазаа...` 3. `ԥхынгәымза нанҳәамза цәыббрамза жьҭаарамза абҵарамза ԥхынҷкәынмза иит рыԥсҭазаара иалҵит клавдиа пул...` ### Generated Text Samples (Subword-based) Below are text samples generated from each subword-based Markov chain model: **Context Size 1:** 1. `аякарамаҟәаҿы_«п` 2. `_жьы_ажәынқәсп_и` 3. `иха_аббарран._ло` **Context Size 2:** 1. `а_уи_ахьы_иркую_с` 2. `_ареит._ара_ихьам` 3. `рала_ԥхын,_хьшара` **Context Size 3:** 1. `араҟнытә_бызшәалеи` 2. `мза_жьҭаарамза_жәа` 3. `за_ԥхынгәырый_фано` **Context Size 4:** 1. `мза_ракәзар,_зныз_х` 2. `амза_рашәара,_шықәс` 3. `рамза_ԥхынгәымза_ла` ### Key Findings - **Best Predictability:** Context-4 (word) with 99.0% predictability - **Branching Factor:** Decreases with context size (more deterministic) - **Memory Trade-off:** Larger contexts require more storage (207,598 contexts) - **Recommendation:** Context-3 or Context-4 for text generation --- ## 4. Vocabulary Analysis ![Zipf's Law](visualizations/zipf_law.png) ![Top Words](visualizations/top20_words.png) ![Coverage Curve](visualizations/vocab_coverage.png) ### Statistics | Metric | Value | |--------|-------| | Vocabulary Size | 32,744 | | Total Tokens | 441,086 | | Mean Frequency | 13.47 | | Median Frequency | 3 | | Frequency Std Dev | 100.78 | ### Most Common Words | Rank | Word | Frequency | |------|------|-----------| | 1 | уи | 4,161 | | 2 | рыԥсҭазаара | 4,025 | | 3 | иит | 3,987 | | 4 | иалҵит | 3,980 | | 5 | лаҵарамза | 3,752 | | 6 | жәабранмза | 3,722 | | 7 | хәажәкырамза | 3,702 | | 8 | абҵарамза | 3,701 | | 9 | нанҳәамза | 3,696 | | 10 | ԥхынҷкәынмза | 3,696 | ### Least Common Words (from vocabulary) | Rank | Word | Frequency | |------|------|-----------| | 1 | sons | 2 | | 2 | extended | 2 | | 3 | stream | 2 | | 4 | block | 2 | | 5 | stru | 2 | | 6 | compressed | 2 | | 7 | deflate | 2 | | 8 | january | 2 | | 9 | видеохәмарроуп | 2 | | 10 | роблокс | 2 | ### Zipf's Law Analysis | Metric | Value | |--------|-------| | Zipf Coefficient | 0.9626 | | R² (Goodness of Fit) | 0.995444 | | Adherence Quality | **excellent** | ### Coverage Analysis | Top N Words | Coverage | |-------------|----------| | Top 100 | 30.3% | | Top 1,000 | 55.7% | | Top 5,000 | 76.9% | | Top 10,000 | 85.7% | ### Key Findings - **Zipf Compliance:** R²=0.9954 indicates excellent adherence to Zipf's law - **High Frequency Dominance:** Top 100 words cover 30.3% of corpus - **Long Tail:** 22,744 words needed for remaining 14.3% coverage --- ## 5. Word Embeddings Evaluation ![Embedding Isotropy](visualizations/embedding_isotropy.png) ![Similarity Matrix](visualizations/embedding_similarity.png) ![t-SNE Words](visualizations/tsne_words.png) ![t-SNE Sentences](visualizations/tsne_sentences.png) ### 5.1 Cross-Lingual Alignment ![Alignment Quality](visualizations/embedding_alignment_quality.png) ![Multilingual t-SNE](visualizations/embedding_tsne_multilingual.png) ### 5.2 Model Comparison | Model | Dimension | Isotropy | Semantic Density | Alignment R@1 | Alignment R@10 | |-------|-----------|----------|------------------|---------------|----------------| | **mono_32d** | 32 | 0.8394 | 0.3485 | N/A | N/A | | **mono_64d** | 64 | 0.5679 | 0.2942 | N/A | N/A | | **mono_128d** | 128 | 0.1636 | 0.2836 | N/A | N/A | | **aligned_32d** | 32 | 0.8394 🏆 | 0.3421 | 0.0220 | 0.1360 | | **aligned_64d** | 64 | 0.5679 | 0.2946 | 0.0360 | 0.1960 | | **aligned_128d** | 128 | 0.1636 | 0.2850 | 0.0420 | 0.2180 | ### Key Findings - **Best Isotropy:** aligned_32d with 0.8394 (more uniform distribution) - **Semantic Density:** Average pairwise similarity of 0.3080. Lower values indicate better semantic separation. - **Alignment Quality:** Aligned models achieve up to 4.2% 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 | **2.615** | High morphological productivity | Reliable analysis | | Idiomaticity Gap | **1.280** | 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 | |--------|----------| | `-иа` | иалаҵоу, иааргазар, иадлоит | #### Productive Suffixes | Suffix | Examples | |--------|----------| | `-а` | акандидатцәа, азура, ашәара | | `-әа` | акандидатцәа, акрақәа, аконсультациақәа | | `-ит` | иҟамлеит, дагәыланахалоит, дашьҭалоит | | `-қәа` | акрақәа, аконсультациақәа, дунеихәаԥшрақәа | | `-ра` | азура, ашәара, рықәцара | | `-тә` | алашаратә, аҵакырадгьылтә, аетнографиатә | | `-еи` | ргәыԥқәеи, астатуиақәеи, аизгақәеи | | `-еит` | иҟамлеит, ԥхасҭахеит, игәарҭеит | ### 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 | |------|----------|------------------|----------| | `гыла` | 1.73x | 82 contexts | гылан, ргылан, дгылан | | `ықәс` | 1.84x | 26 contexts | шықәс, щықәса, ашықәс | | `әыла` | 1.68x | 34 contexts | тәыла, тәылак, ртәыла | | `аҵар` | 1.63x | 38 contexts | аҵара, лаҵара, аҵареи | | `қәса` | 1.96x | 16 contexts | щықәса, шықәса, шиқәсазы | | `арам` | 1.86x | 17 contexts | харам, нарам, гуарам | | `азаа` | 1.69x | 23 contexts | лазаа, амазаап, иазааит | | `әара` | 1.30x | 58 contexts | шәара, акәара, ҿҳәара | | `ҭаза` | 2.37x | 8 contexts | иԥсҭазара, ԥсҭазаара, иԥсҭазаара | | `шәар` | 1.56x | 26 contexts | шәара, шәарах, ашәара | | `заар` | 2.09x | 10 contexts | акзаара, аҟазаара, акзаареи | | `ыҳәа` | 1.57x | 22 contexts | ныҳәа, рныҳәа, иныҳәа | ### 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 | |--------|--------|-----------|----------| | `-иа` | `-ит` | 83 words | иаабоит, иацхраауеит | | `-иа` | `-еит` | 50 words | иацхраауеит, иартәеит | | `-иа` | `-а` | 43 words | ианырба, ианрылага | | `-иа` | `-әа` | 11 words | иацәыхарамкәа, иаламлакәа | | `-иа` | `-тә` | 5 words | иааникыларатә, иавтобиографиатә | | `-иа` | `-ра` | 3 words | иавторра, иамхра | | `-иа` | `-еи` | 2 words | ианԥсеи, иашьцәеи | | `-иа` | `-қәа` | 2 words | иажәақәа, иажәамаанақәа | | `-иа` | `-ақәа` | 1 words | иажәақәа, иажәамаанақәа | ### 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 | |------|-----------------|------------|------| | анхарҭатә | **`анхарҭа-тә`** | 4.5 | `анхарҭа` | | рхыԥхьаӡараҟнытә | **`рхыԥхьаӡараҟны-тә`** | 4.5 | `рхыԥхьаӡараҟны` | | аӡхықәқәа | **`аӡхықә-қәа`** | 4.5 | `аӡхықә` | | астуденттә | **`астудент-тә`** | 4.5 | `астудент` | | аҳәынҭқарқәа | **`аҳәынҭқар-қәа`** | 4.5 | `аҳәынҭқар` | | каталониатә | **`каталониа-тә`** | 4.5 | `каталониа` | | абиблиографиатә | **`абиблиографиа-тә`** | 4.5 | `абиблиографиа` | | аредакциатә | **`аредакциа-тә`** | 4.5 | `аредакциа` | | амилициатә | **`амилициа-тә`** | 4.5 | `амилициа` | | амилаҭқәа | **`амилаҭ-қәа`** | 4.5 | `амилаҭ` | | аекологиатә | **`аекологиа-тә`** | 4.5 | `аекологиа` | | адемографиатә | **`адемографиа-тә`** | 4.5 | `адемографиа` | | аконсервациатә | **`аконсервациа-тә`** | 4.5 | `аконсервациа` | | ауаҩытәыҩсатә | **`ауаҩытәыҩса-тә`** | 4.5 | `ауаҩытәыҩса` | | аелементқәа | **`аелемент-қәа`** | 4.5 | `аелемент` | ### 6.6 Linguistic Interpretation > **Automated Insight:** The language Abkhazian 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 ![Performance Dashboard](visualizations/performance_dashboard.png) ### Production Recommendations | Component | Recommended | Rationale | |-----------|-------------|-----------| | Tokenizer | **64k BPE** | Best compression (4.19x) | | N-gram | **5-gram** | Lowest perplexity (198) | | Markov | **Context-4** | Highest predictability (99.0%) | | 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) × 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. **R² (Coefficient of Determination)** > *Definition:* Measures how well the linear fit explains the frequency-rank relationship. Ranges from 0 to 1. > > *Intuition:* R² near 1.0 means the data closely follows Zipf's law; lower values indicate deviation from expected word frequency patterns. > > *What to seek:* R² > 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 1. **Compare within model families:** Metrics are most meaningful when comparing models of the same type (e.g., 8k vs 64k tokenizer). 2. **Consider trade-offs:** Better performance on one metric often comes at the cost of another (e.g., compression vs. OOV rate). 3. **Context matters:** Optimal values depend on downstream tasks. Text generation may prioritize different metrics than classification. 4. **Corpus influence:** All metrics are influenced by corpus characteristics. Wikipedia text differs from social media or literature. 5. **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](https://huggingface.co/datasets/omarkamali/wikipedia-monthly) - a monthly snapshot of Wikipedia articles across 300+ languages. ### Project A project by **[Wikilangs](https://wikilangs.org)** - Open-source NLP models for every Wikipedia language. ### Maintainer [Omar Kamali](https://omarkamali.com) - [Omneity Labs](https://omneitylabs.com) ### Citation If you use these models in your research, please cite: ```bibtex @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 - 🌐 Website: [wikilangs.org](https://wikilangs.org) - 🤗 Models: [huggingface.co/wikilangs](https://huggingface.co/wikilangs) - 📊 Data: [wikipedia-monthly](https://huggingface.co/datasets/omarkamali/wikipedia-monthly) - 👤 Author: [Omar Kamali](https://huggingface.co/omarkamali) - 🤝 Sponsor: [Featherless AI](https://featherless.ai) --- *Generated by Wikilangs Models Pipeline* *Report Date: 2026-01-03 16:16:58*