Base Difficulty

Base difficulty: Level 135 edit

Level distribution for noun (natural_feature): 10: 2 11: 1 135: 25 165: 1 219: 26 254: 1 330: 1 1010: 1 1020: 7 1050: 9 1221: 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: 1502 (weighted harmonic mean of corpus + tier signals; lower = more common)
Tier Signals
Source Tier Rank used
basic_english Extended (2 of 2) 1600
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 41.40 2521 100% 1945 2
20th_books 87.28 1416 100% 974 3
wiki_math 0.00 — — — 0
wiki_geography 516.94 501 100% 252 3
wiki_biology 75.57 2728 100% 1694 2
wiki_modern_life 41.90 3415 100% 3415 1
wiki_arts 31.75 4117 100% 4117 1
wiki_society 25.50 4932 100% 4932 1
wiki_linguistics 82.75 2347 100% 1378 2
wiki_physical_science 181.40 1928 100% 772 3
wiki_history 130.68 1765 100% 1044 2
early_modern_science 162.43 1055 100% 708 2
religious_translated 90.31 1473 100% 1075 2
cooking 0.00 — — — 0
legal_scotus 24.08 4002 100% 4002 1
eu_parliament_debates 0.00 — — — 0
openstax_science 0.00 — — — 0
openstax_society 73.51 2859 100% 1664 2
wpa_life_histories 122.85 1603 100% 730 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.