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: 528 (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 150.46 721 100% 616 2
20th_books 104.75 1071 100% 880 2
wiki_math 95.86 2036 100% 1045 2
wiki_geography 124.57 1983 100% 1118 2
wiki_biology 166.69 1421 100% 833 2
wiki_modern_life 411.35 616 100% 308 2
wiki_arts 193.60 1060 100% 708 2
wiki_society 282.08 692 100% 472 2
wiki_linguistics 219.27 1006 100% 594 2
wiki_physical_science 157.38 1471 100% 914 2
wiki_history 120.05 1679 100% 1125 2
early_modern_science 340.96 403 100% 322 2
religious_translated 208.08 590 100% 509 2
cooking 318.89 560 100% 400 2
legal_scotus 1124.25 165 100% 95 2
eu_parliament_debates 182.10 977 100% 635 2
openstax_science 124.26 1908 100% 1070 2
openstax_society 212.47 977 100% 662 2
wpa_life_histories 68.12 1902 100% 1290 2

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.