Data_Sheet_1_Examination of Gender-Related Differential Item Functioning Through Poly-BW Indices.PDF

The existing differential item functioning (DIF) detection approaches relying on item difficulty or item discrimination are limited for understanding the associates of DIF items, and consequently, DIF items were conventionally either deleted or ignored. Given the importance of minimizing DIF items in test construction, teachers or testing practitioners need more information regarding possible associates of DIF items. Using an example of a teacher-made mathematics achievement test, this study aimed to examine how the Poly-BW indices (power, defenselessness, disturbance, and hint) contributed to the properties of gender-related DIF items. Data from a 34-item mathematics achievement test that involved 1,439 seventh-grade students from Taiwan (51.01% boys and 48.99% girls) showed that the differences of the defenselessness (mp) and power (cp) indices between men and women served as salient predictors of the DIF measures estimated by the Poly Simultaneous Item Bias Test (Poly-SIBTEST) procedure and with satisfactory accuracy of hit rates. Items with relatively large defenselessness for men were likely to present male-favoring DIFs, whereas items with relatively large power for men were likely to present female-favoring DIFs. The Poly-BW indices yielded directions for modifying items for teachers in practice.

现有依赖项目难度（item difficulty）与项目区分度（item discrimination）的项目功能差异（differential item functioning, DIF）检测方法，在解析DIF项目的关联成因时存在局限，因此传统上对DIF项目要么直接删除，要么予以忽略。鉴于测验编制中最小化DIF项目的重要性，教师及测验从业者需要更多关于DIF项目潜在关联成因的信息。本研究以教师自编的数学成就测验为实例，旨在探究Poly-BW指标（power、defenselessness、disturbance及hint）对性别相关DIF项目属性的影响。本研究采用包含34道试题的数学成就测验数据，样本为我国台湾地区1439名七年级学生（男生占比51.01%，女生占比48.99%）。分析结果显示，男女在无助感（defenselessness, mp）与权力（power, cp）指标上的差异，可作为Poly同时性项目偏倚检验（Poly Simultaneous Item Bias Test, Poly-SIBTEST）程序所估计的DIF量的显著预测因子，且模型命中准确率表现良好。男生无助感得分相对较高的项目，更易呈现男性偏向的DIF；而男生权力得分相对较高的项目，更易呈现女性偏向的DIF。Poly-BW指标可为一线教师的项目修改工作提供明确方向。