Base Difficulty

Base difficulty: Level 470 edit

Level distribution for verb (development): 30: 1 165: 2 170: 1 179: 1 196: 1 249: 1 278: 1 299: 2 300: 1 329: 1 470: 7 475: 1 1399: 6

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: 5221 (weighted harmonic mean of corpus + tier signals; lower = more common)
Tier Signals
Source Tier Rank used
cambridge_yle Flyers (3 of 3) 1200
cefr A1 (1 of 6) 800

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 33.26 841 20% 2662 downrated 4
20th_books 24.32 1074 20% 3650 downrated 3
wiki_math 0.00 — — — 0
wiki_geography 29.09 927 20% 4635 downrated 1
wiki_biology 8.73 3057 20% 9000 capped 1
wiki_modern_life 5.32 4943 20% 10000 capped 1
wiki_arts 26.43 2514 20% 5152 downrated 3
wiki_society 8.28 3331 20% 11000 capped 1
wiki_linguistics 16.45 2080 20% 6978 downrated 2
wiki_physical_science 0.00 — — — 0
wiki_history 44.58 699 20% 2894 downrated 2
early_modern_science 32.05 1075 20% 3574 downrated 2
religious_translated 18.08 1990 20% 4930 downrated 3
cooking 0.00 — — — 0
legal_scotus 8.74 4597 20% 8274 downrated 4
eu_parliament_debates 10.65 3053 20% 7877 downrated 2
openstax_science 4.74 4480 20% 11000 capped 1
openstax_society 21.74 1767 20% 6021 downrated 2
wpa_life_histories 30.65 867 20% 3081 downrated 3

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.