Base Difficulty

Base difficulty: Level 221 edit

Level distribution for noun (physical_phenomenon): 135: 3 162: 4 179: 1 219: 1 221: 1 274: 2 275: 2 280: 1 285: 1 290: 2 300: 2 350: 1 380: 1 400: 1 440: 2 1399: 12

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: 496 (weighted harmonic mean of corpus + tier signals; lower = more common)
Tier Signals
Source Tier Rank used
basic_english Basic (1 of 2) 600
cambridge_yle Flyers (3 of 3) 1200
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 289.97 452 100% 347 2
20th_books 338.23 392 100% 303 2
wiki_math 50.81 2003 100% 2003 1
wiki_geography 0.00 — — — 0
wiki_biology 277.46 783 100% 494 2
wiki_modern_life 180.55 936 100% 771 2
wiki_arts 722.19 173 100% 144 2
wiki_society 58.18 2403 100% 2403 1
wiki_linguistics 1641.28 124 100% 71 2
wiki_physical_science 196.29 738 100% 738 1
wiki_history 77.81 1744 100% 1744 1
early_modern_science 173.14 794 100% 639 2
religious_translated 192.98 692 100% 541 2
cooking 29.30 2460 100% 2460 1
legal_scotus 75.08 1864 100% 1495 2
eu_parliament_debates 88.29 1316 100% 1316 1
openstax_science 281.78 666 100% 495 2
openstax_society 133.52 1668 100% 1012 2
wpa_life_histories 108.23 1262 100% 868 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.