Katholieke Universiteit Leuven, Belgium GROEP T - Leuven Education College, Belgium.
Br J Psychol. 2011 Aug;102(3):585-97. doi: 10.1111/j.2044-8295.2011.02019.x. Epub 2011 Mar 31.
This study examined adults' use of indirect addition and direct subtraction strategies on multi-digit subtractions in the number domain up to 1,000. Seventy students who differed in their level of arithmetic ability solved multi-digit subtractions in one choice and two no-choice conditions. Against the background of recent findings in elementary subtraction, we manipulated the size of the subtrahend compared to the difference and only selected items with large distances between these two integers. Results revealed that adults frequently and efficiently apply indirect addition on multi-digit subtractions, yet adults with higher arithmetic ability performed more efficiently than those with lower arithmetic ability. In both groups, indirect addition was more efficient than direct subtraction both on subtractions with a subtrahend much larger than the difference (e.g., 713 - 695) and on subtractions with a subtrahend much smaller than the difference (e.g., 613 - 67). Unexpectedly, only adults with lower arithmetic ability fitted their strategy choices to their individual strategy performance skills. Results are interpreted in terms of mathematical and cognitive perspectives on strategy efficiency and adaptiveness.
本研究考察了成年人在数字域中进行的 1000 以内多位数减法时使用间接加法和直接减法策略的情况。70 名算术能力不同的学生在一种选择和两种无选择条件下解决了多位数减法问题。根据小学减法的最新发现，我们操纵了被减数与差的大小，并只选择了这两个整数之间距离较大的项目。结果表明，成年人经常有效地在多位数减法中使用间接加法，但算术能力较高的成年人比算术能力较低的成年人效率更高。在这两组中，间接加法在被减数远大于差（例如 713-695）和被减数远小于差（例如 613-67）的减法中都比直接减法更有效。出乎意料的是，只有算术能力较低的成年人根据自己的策略表现技能来调整策略选择。研究结果从数学和认知的角度解释了策略效率和适应性。
