基于试题库组卷的最小题量的构建

The Modeling of the Minimum Amount of the Items in a Test Database

网络环境下,利用试题库共组卷2m份,要求前m份试卷没有重题,而从第(m+1)份试卷起,每份试卷中出现前m份试卷用过试题的概率不超过某个限定值。在此条件下,利用有关的概率统计理论,构建了试题库所需的最小题量的模型,以及一份试卷中出现用过试题数的期望。最后,以一个例子说明该模型的应用。

In network instruction, we use the test database to generate 2m test papers to check theeffect of learning. We assume that test items taken from the database cannot be repetitive in the beginningm papers, and from the （m＋1） to 2m paper, the probability of the used items to occur is restrictedto a certain limit. The modeling of the minimum amount of the items in a test database is derived by theuse of the probability theory. The mathematical expectation for the amount of used test items in a testpaper is analyzed. At last, an example is given as an illustration for the feasibility of the model.