预估难度的理论模型及应用探析

难度决定考试分数的分布,直接影响考试的评价与选拔功能,受到较高的关注。难度一般通过考后对考试数据的统计分析得到,这时合格分数线巴经确定,无法再进行调整。预估难度是在命题阶段由命题专家结合试题内容,通过构建标准常模,进行合理地评定而得到的试题难度。在当前应用愿始分报告考试成绩的情况下,预估难度对确保考试稳定与公平尤其重要。预估难度不同于实测难度,可以进行控制与调整。命题工作不仅是编制试题的过程,而且是预估难度的设计过程。

Study of the Model and Application for Estimated Difficulty

Test score is mainly calculated by the items'difficulties,which affect the function of judgment and selection to the candidate directly.Difficulty,a very important to evaluate the item,is a fixed parameter after testing,when the cut-off score is deciding.The Estimated Difficulty,a model to estimate the item difficulty by test developers,is founded by constructing the Standard Norm Group of test takers,applied in the test developing process.The Model can keep the test stable and equity greatly by raw score.T...