Peters Greet, De Smedt Bert, Torbeyns Joke, Ghesquière Pol, Verschaffel Lieven
Centre for Instructional Psychology and Technology, K.U.Leuven, Belgium.
Acta Psychol (Amst). 2010 Nov;135(3):323-9. doi: 10.1016/j.actpsy.2010.08.007.
The present study investigates adults' use of addition to solve two-digit subtractions. Inspired by research on single-digit arithmetic, we first examined regression models in which different problem characteristics predicted participants' reaction times. Second, we compared performance on two-digit subtractions presented in 2 presentation formats, i.e., the standard subtraction format (81-37=.) and an addition format (37+.=81). Both methods lead to the conclusion that the participants switched between direct subtraction and subtraction by addition depending on the relative size of the subtrahend: If the subtrahend was smaller than the difference, direct subtraction was mainly used; if the subtrahend was larger than the difference, subtraction by addition was the dominant strategy. However, this performance pattern was only observed when the distance between the subtrahend and the difference was large; when the subtrahend and the difference were close to each other, there was no subtrahend-dependent selection of direct subtraction vs. subtraction by addition. These data indicate that theoretical models of people's strategy choices in subtraction should include the relative size of the subtrahend as an important factor in the strategy selection process.
本研究调查了成年人运用加法来解决两位数减法的情况。受个位数算术研究的启发，我们首先检验了回归模型，其中不同的问题特征预测了参与者的反应时间。其次，我们比较了以两种呈现形式给出的两位数减法的表现，即标准减法形式（81 - 37 = .）和加法形式（37 + . = 81）。两种方法均得出结论：参与者会根据减数的相对大小在直接减法和加法减法之间进行切换：如果减数小于差，则主要使用直接减法；如果减数大于差，则加法减法是主要策略。然而，只有当减数与差之间的距离较大时，才会观察到这种表现模式；当减数与差彼此接近时，不存在依赖减数的直接减法与加法减法的选择。这些数据表明，人们减法策略选择的理论模型应将减数的相对大小作为策略选择过程中的一个重要因素。
