The greater of two multidigit integers could be chosen by (a) generating and comparing internal representations of the integers (holistic models), (b) sequentially comparing corresponding digits in the integers (sequential place-value models), or (c) simultaneously comparing corresponding digits (parallel place-value models).In Experiments 1 and 2, subjects chose the greater of 2 four-digit or 2 six-digit integers. As predicted by sequential place-value models, latencies did not depend on the number of unequal digits in the two numbers, and latencies increased linearly with the position of the leftmost unequal digits except when only the rightmost digits were unequal. In Experiment 3, latencies increased linearly for all positions when two letters were presented to the right of the integers. These results imply that multidigit integers are compared by sequentially comparing digits.

Prognostic and epidemiologic study, level III.