Base Difficulty

Base difficulty: Level 455 edit

Level distribution for verb (perception): 5: 1 8: 2 185: 1 205: 1 214: 12 230: 1 265: 1 279: 1 455: 1 1040: 1 1399: 4

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: 1352 (weighted harmonic mean of corpus + tier signals; lower = more common)
Tier Signals
Source Tier Rank used
cefr B1 (3 of 6) 4200

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 46.10 2459 80% 1834 2
20th_books 34.66 2815 80% 2248 2
wiki_math 197.02 1249 80% 507 5
wiki_geography 0.00 — — — 0
wiki_biology 266.42 1164 80% 508 5
wiki_modern_life 76.60 2948 80% 1893 2
wiki_arts 90.92 2000 80% 1514 2
wiki_society 167.37 1667 80% 823 4
wiki_linguistics 524.63 551 80% 245 6
wiki_physical_science 103.42 2189 80% 1374 2
wiki_history 41.44 2628 80% 3285 downrated 1
early_modern_science 116.34 1354 80% 989 2
religious_translated 78.05 1445 80% 1252 2
cooking 0.00 — — — 0
legal_scotus 141.95 1766 80% 766 5
eu_parliament_debates 11.81 4503 80% 5629 downrated 1
openstax_science 140.56 2239 80% 867 4
openstax_society 48.61 3093 80% 2407 2
wpa_life_histories 8.96 5992 80% 7490 downrated 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.