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Title: Do children's number words begin noisy?

How do children acquire exact meanings for number words likethreeorforty‐seven? In recent years, a lively debate has probed the cognitive systems that support learning, with some arguing that an evolutionarily ancient “approximate number system” drives early number word meanings, and others arguing that learning is supported chiefly by representations of small sets of discrete individuals. This debate has centered around the findings generated by Wynn's (,) Give‐a‐Number task, which she used to categorize children into discrete “knower level” stages. Early reports confirmed Wynn's analysis, and took these stages to support the “small sets” hypothesis. However, more recent studies have disputed this analysis, and have argued that Give‐a‐Number data reveal a strong role for approximate number representations. In the present study, we use previously collected Give‐a‐Number data to replicate the analyses of these past studies, and to show that differences between past studies are due to assumptions made in analyses, rather than to differences in data themselves. We also show how Give‐a‐Number data violate the assumptions of parametric tests used in past studies. Based on simple non‐parametric tests and model simulations, we conclude that (a) before children learn exact meanings for words likeone, two, three,andfour,they first acquire noisy preliminary meanings for these words, (b) there is no reliable evidence of preliminary meanings for larger meanings, and (c) Give‐a‐Number cannot be used to readily identify signatures of the approximate number system.

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Developmental Science
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National Science Foundation
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