Lazarte A A, Schönemann P H
Purdue University, West Lafayette, Indiana.
Percept Psychophys. 1991 Feb;49(2):142-58. doi: 10.3758/bf03205034.
Previous findings that dissimilarity judgments for rectangles are strongly subadditive, that qualitative individual differences are always present, and that four-parameter psychophysical maps can reproduce the average ratings (Schönemann & Lazarte, 1987) are replicated. However, the present study in addition suggests that the metric for bounded response transformation, previously used to restore additivity of responses, has a modest effect on the fits of the psychophysical maps. The differential weighing of the coordinates already incorporates segmental subadditivity predictions into the maps. In fact, the psychophysical maps define a subadditive saliency metric that depends on assigning larger weights to larger coordinates. This constraint on the weights of these maps, together with the response times, allows us to identify a strategy shift when subjects respond to two classes of stimulus pairs: For rectangle-rectangle pairs, subjects center on the shape and size of the rectangles; for square-rectangle pairs, the focus is on height and width.
先前的研究结果得到了重复，即对矩形的差异判断具有强烈的次可加性，定性的个体差异总是存在，并且四参数心理物理映射可以重现平均评分（舍内曼和拉扎特，1987年）。然而，本研究还表明，先前用于恢复反应可加性的有界反应转换度量对心理物理映射的拟合有适度影响。坐标的差异加权已经将分段次可加性预测纳入映射中。事实上，心理物理映射定义了一种次可加性显著度量，该度量依赖于为更大的坐标赋予更大的权重。这些映射权重上的这种约束，连同反应时间，使我们能够识别出当受试者对两类刺激对做出反应时的策略转变：对于矩形 - 矩形对，受试者关注矩形的形状和大小；对于正方形 - 矩形对，关注点在于高度和宽度。
