Base Difficulty

Base difficulty: Level 170 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: 758 (weighted harmonic mean of corpus + tier signals; lower = more common)
Tier Signals
Source Tier Rank used
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 193.83 764 97% 478 3
20th_books 195.02 759 97% 482 3
wiki_math 48.21 2038 97% 2099 downrated 1
wiki_geography 68.29 1993 97% 2053 downrated 1
wiki_biology 183.56 1349 97% 746 3
wiki_modern_life 212.40 1267 97% 689 3
wiki_arts 118.68 1680 97% 1158 2
wiki_society 163.97 1756 97% 852 3
wiki_linguistics 117.40 1497 97% 1042 2
wiki_physical_science 33.39 3631 97% 3740 downrated 1
wiki_history 216.92 919 97% 611 3
early_modern_science 165.51 1101 97% 673 3
religious_translated 214.99 753 97% 484 3
cooking 123.62 1421 97% 788 2
legal_scotus 393.77 889 97% 325 4
eu_parliament_debates 339.25 670 97% 332 4
openstax_science 108.14 3285 97% 1041 4
openstax_society 340.32 1129 97% 407 4
wpa_life_histories 360.92 555 97% 283 4

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.