Contextual Sensitivity and the Large Number Word Bias: When Is Bigger Really More?

Number words can be confusing, even beyond early stages of number word acquisition. In this chapter we describe possible sources of this confusion, and propose that children's awareness of the inherent ambiguity of some numerical statements may be a unique and overlooked aspect of their "number sense." We further propose that this potential source of individual differences may be systematically measured by testing children's sensitivity to number words in context. For example, some children's magnitude comparison judgments conform to a large number word bias; and the strength of this bias varies with context. Future research is needed to develop and test measures of such contextual sensitivity in number word interpretation, to develop models linking the role of numerical ambiguity to formal early mathematics learning, and to test whether responses to numerical ambiguity reflect numerical abilities specifically or foundational skills such as executive function and metacognition.