Base Difficulty

Base difficulty: Level 221 edit

Level distribution for noun (concept_idea): 19: 2 26: 1 27: 1 221: 28 270: 30 274: 30 275: 28 280: 25 300: 1 360: 1 380: 2 1000: 1 1030: 1 1060: 5 1070: 6 1110: 4 1120: 4 1399: 66

Per-Language Difficulty Overrides

No difficulty overrides set. The base difficulty level will be used for all languages.

Add Difficulty Override
-1 to exclude, 1-1399 for level
Frequency and Tier Signals
Combined Frequency Rank: 4105 (weighted harmonic mean of corpus + tier signals; lower = more common)
Tier Signals
Source Tier Rank used
basic_english Basic (1 of 2) 600
cefr A2 (2 of 6) 2100

Rank used = synthetic rank this tier contributes to the combined frequency rank (lower = more common).

Corpus Frequency
Corpus Freq (per M) Best form Share Zipf rank Forms
19th_books 3.67 2200 9% 20000 capped 1
20th_books 3.33 2308 9% 20000 capped 1
wiki_math 8.19 1350 9% 8000 capped 1
wiki_geography 25.67 511 9% 4898 downrated 2
wiki_biology 22.01 733 9% 6183 downrated 2
wiki_modern_life 38.84 265 9% 2698 downrated 2
wiki_arts 16.67 853 9% 7897 downrated 2
wiki_society 37.24 286 9% 2943 downrated 2
wiki_linguistics 15.59 906 9% 8066 downrated 2
wiki_physical_science 12.19 1093 9% 8000 capped 1
wiki_history 44.82 194 9% 2134 downrated 1
early_modern_science 8.84 1203 9% 10400 capped 1
religious_translated 5.10 1777 9% 10400 capped 1
cooking 0.00 — — — 0
legal_scotus 57.61 182 9% 1804 downrated 2
eu_parliament_debates 126.05 90 9% 924 downrated 2
openstax_science 30.41 512 9% 4480 downrated 2
openstax_society 66.70 156 9% 1627 downrated 2
wpa_life_histories 4.16 2021 9% 20000 capped 1

Best form = the single best-ranked form in the corpus, share-blind — how the spelling itself ranked. Share = how much of that spelling belongs to this lemma, when several senses compete for it. Zipf rank = all the forms combined (variant spellings included), each scaled by its share, and what feeds the combined frequency rank. Combining forms improves on the best form, but a share below 100% pushes the other way and usually wins: a sense holding a small slice of a common spelling is a rare word, so its rank lands downrated below the best form — and once it falls past what the corpus can support it is capped at the rank an unlisted word would get.