A/B test
C1CEFR level
55/100Rarity: uncommon
TechnicalRegister
A controlled experiment that randomly splits users between two variants to measure which performs better on a chosen metric.
We ran an A/B test on the pricing page and the shorter copy won by 6%.
Rarity runs from 0 (a word everyone knows) to 100 (almost never seen outside specialist or literary writing). Level is the word's real difficulty on the CEFR scale, from A1 to C2.
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