Department of Psychology, Carnegie Mellon University, Pittsburgh, PA, USA.
The Siegler Center for Innovative Learning (SCIL), Advanced Technology Center, Beijing Normal University, Beijing, China.
Dev Sci. 2018 Mar;21(2). doi: 10.1111/desc.12541. Epub 2017 Feb 22.
Many students' knowledge of fractions is adversely affected by whole number bias, the tendency to focus on the separate whole number components (numerator and denominator) of a fraction rather than on the fraction's magnitude (ratio of numerator to denominator). Although whole number bias appears early in the fraction learning process and under speeded conditions persists into adulthood, even among mathematicians, little is known about its development. Performance with equivalent fractions indicated that between fourth and eighth grade, whole number bias decreased, and reliance on fraction magnitudes increased. These trends were present on both fraction magnitude comparison and number line estimation. However, analyses of individual children's performance indicated that a substantial minority of fourth graders did not show whole number bias and that a substantial minority of eighth graders did show it. Implications of the findings for development of understanding of fraction equivalence and for theories of numerical development are discussed.
许多学生的分数知识受到整数偏见的不利影响，这种偏见倾向于关注分数的单独整数部分（分子和分母），而不是分数的大小（分子与分母的比率）。尽管整数偏见在分数学习过程中很早就出现了，而且在加速条件下一直持续到成年期，即使在数学家群体中，人们对其发展也知之甚少。等效分数的表现表明，从四年级到八年级，整数偏见减少，对分数大小的依赖增加。这些趋势在分数大小比较和数字线估计上都存在。然而，对个别儿童表现的分析表明，相当一部分四年级学生没有表现出整数偏见，而相当一部分八年级学生则表现出整数偏见。这些发现对分数等价理解的发展以及对数值发展理论的意义进行了讨论。
