We have collected age-of-acquisition (AoA) ratings for 31K English content words (nouns, verbs, adjectives). The collection of these new AoA norms was possible because we made use of the web-based crowdsourcing technology offered by the Amazon Mechanical Turk. Correlations with existing AoA measures suggest that these estimates are as good as the existing ones.
Because the Age-of-acquisition norms can also be used for inflected forms, we can expand the original list to a total of 51+K words, meaning that AoA can now be included in all word recognition studies (it still explains 5% of the variance in lexical decision times after word frequency, length, and OLD20 are controlled for).
You find various files with the ratings at http://crr.ugent.be/archives/806
Kuperman, V.,Stadthagen-Gonzalez, H., & Brysbaert, M. (in press). Age-of-acquisition ratings for 30 thousand English words. Behavior Research Methods.
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