Dehaene S
Percept Psychophys. 1989 Jun;45(6):557-66. doi: 10.3758/bf03208063.
Reaction-time studies of numerical comparison have used essentially two paradigms: classification, in which a target number must be labelled "larger" or "smaller" in comparison to a fixed standard, and selection, in which the larger (or smaller) number of a pair must be picked out. In previous studies, classification has yielded only a distance effect in RTs, whereas selection has also revealed magnitude (or minimum) and congruity effects. We used two experiments with two-digit number comparisons to find the reason for this discrepancy. In Experiment 1, we used a variant of the classification task with the standard changing on each trial. RTs increased along with the standard for "smaller" responses and decreased along with the standard for "larger" responses, in a manner reminiscent of magnitude and congruity effects. In Experiment 2, we again used classification, but the fixed standard 75 was not at the center of the range of target numbers (20, 21, ... 99). Close to the standard, RTs were faster for "larger" than for "smaller" responses, again a congruity effect. Our data show that magnitude and congruity effects can be obtained with two-digit numbers in classification as well as in selection tasks. A single equation, which implies that numbers are compared with respect to reference points at both ends of the continuum, describes the results from both tasks.
分类，即必须将目标数字标记为相对于固定标准的“更大”或“更小”；以及选择，即必须从一对数字中挑选出更大（或更小）的数字。在先前的研究中，分类仅在反应时间上产生了距离效应，而选择还揭示了大小（或最小值）和一致性效应。我们进行了两项两位数比较的实验，以找出这种差异的原因。在实验1中，我们使用了分类任务的一种变体，标准在每次试验中都会改变。对于“更小”反应，反应时间随着标准的增加而增加，对于“更大”反应，反应时间随着标准的降低而降低，这种方式让人联想到大小和一致性效应。在实验2中，我们再次使用了分类，但固定标准75不在目标数字范围（20、21、...99）的中心。接近标准时，“更大”反应的反应时间比“更小”反应的更快，这也是一种一致性效应。我们的数据表明，在分类任务以及选择任务中，两位数都可以获得大小和一致性效应。一个单一的方程，意味着数字是相对于连续体两端的参考点进行比较的，描述了这两项任务的结果。
