题库建设讲话(2)

Notes on Item Banking Part Two

单参数模式的难度值与能力值估算1.PROX程序在上一讲里,我们谈到把答对率转换成对数单位的方法。我们不能不看到,这种方法过于粗糙,因为它没有考虑到能力和项目难度的分布,即其差异的情况。因此有必要对它们加以校正。

A continuation of Part One which deals with the prerequisites to and the mathematical models of item banking. Part Two concentrates on the estimation of item and ability parameters of the one-pa-rameter model of item respoase theory. The PROX procedure and the UCON procedure proposedby Wright and Stone are introduced to show how item difficulties and person abilities canbe put on the same scale. Then the UFORM procedure is compared with the Newton-Raphsoniterative method to show how items from a bank can be made used of to estimate theabilities of the subjects.